The Fasting Cheatsheet (In Progress)

Intermittent Fasting

Why Intermittent Fasting?

The eating patterns of our hunter-gatherer ancestors were highly unpredictable. They were always in between fasting and feasting. They did both intermittently. This cycle wasn’t deliberate but created by the scarcity of food in their environment.

The two governing states of metabolism are fed and fasted – anabolism and catabolism. The former is when we’re using the macronutrients eaten, that have been digested and are now circulating the bloodstream. The latter happens when all that fuel has run out and our gas tank is empty, so to say. It happens after several hours (7-8) of not eating.

Here’s what to do to increase protein absorption with intermittent fasting:

Exercising before food will also deplete your body’s glycogen stores which makes the muscle cells more eager to absorb carbohydrates from food. Every food that’s used for recovering from exercise will be prioritized much higher for both muscle growth and maximal absorption.
Before eating you want to create an acidic intestinal environment by stimulating the production of hydrochloric acid (HCl) in the gut. Foods high in HCl are lemons, celery, olives, and vinegar.
Warm lemon water with apple cider vinegar is great for blunting the blood sugar response of eating and helps with digestion. Ginger, in particular, helps with protein absorption.
Before eating you also want to put yourself into a parasympathetic state and become relaxed. If you’re stressed out or are feeling anxious, then your adrenals will direct blood flow away from the gut into the extremities. This is going to shut down digestion and promotes constipation. That’s why never eat when you’re stressed out and always sit down with your meal. Chewing your food is also incredibly important because it’s going to make it easier for your gut to absorb it. Don’t eat on the run and always be mindful of what you put into your mouth.
Pre-biotics are plant fibers that travel through the intestines unchanged and they help with digestion by feeding the bacteria in your gut. Pre-biotic foods you should eat as the first part of your meal are garlic, onions, asparagus, leeks, artichokes, dandelion, chicory root, and green bananas.
Probiotics promote the creation of live bacteria in your gut that are going to help with breaking down the nutrients from your food. They’re microorganisms that are going to influence your mood, your immune system, your cognitive functioning, and body composition. Therefore, you want to maintain a healthy gut flora by eating fermented foods like sauerkraut, pickles, kimchi, olives, miso, raw kefir, and even very dark chocolate.
Combining large amounts of protein with starches and carbohydrates are also going to inhibit the digestion of those foods because they require different digestive enzymes. That’s why animal foods are best eaten with just vegetables and fermented foods. If you do eat starch then it should be easily digestible cooked starch like sweet potatoes, white potatoes, white rice, or buckwheat.
Slow walking after your meal is also going to lower the blood sugar response from what you ate and helps with digestion. It has to be a very slow and peaceful stroll because if you become too sympathetic, you’ll shut down the digestion again.

Here are a few of the other renown ways of doing IF:

24-Hour Fast. – This is the most basic way. It doesn’t even have to mean that you actually go through a day without eating. Simply have dinner in the evening, fast throughout the next day and eat dinner again. This one is also prescribed by the author of Eat Stop Eat, Brad Pilon. The frequency of these fasts depends on the person but once or twice a week should be the golden standard. An active person who trains hard should do it less often than a sedentary person. The leaner you are the less you have to fast, but that doesn’t mean you can’t gain all of the other physiological enhancements from occasional abstinence.
16/8 Lean-gains Protocol – This is one the most popular strategies, popularized by Martin Berkhan of Leangains. You fast for 16 hours and have a feeding window of 8. Simply skip breakfast and have it during lunch instead. Instead of following 16/8 we can do 14/10, 18/6, 20/4 or whatever fits the situation. The idea is to simply reduce the amount of time we spend in a fed state and to be fasting the majority of the day.
The Warrior Diet is a fasting protocol created by Ori Hofmekler. The entire concept is based around ancient warrior nations, such as the Spartans and Romans, who would be physically active throughout the day and eat mostly in the evening. At daylight, they would only get a few bites here and there and would consume a lot of calories with dinner. This diet follows the 20/4 timeframe with one massive meal eaten at dinner.
One Meal a Day (OMAD) – It’s the simplest way of eating – just eat once a day. Usually, you fast for about 22 hours and eat your food within a 1–2-hour timeframe. This works best for weight loss because you’ll be quite full and thus can effortlessly stay at a caloric deficit. If you do it with proper keto-adaptation, then you’ll also preserve more muscle. However, this may not be ideal for muscle growth because of the limited protein synthesis and anabolism. Instead, the Targeted Intermittent Fasting Protocol I’m going to share with you shortly is the enhanced version of OMAD.
36-Hour Fasts – In this case, you abstain from eating anything for 1 entire day + 12 hours. It’s not actually difficult at all. You simply have dinner the previous night, don’t eat anything in the morning, lunch nor evening, go to bed in a fasted state, wake up the next day, fast a few hours more and start eating again. Going to bed hungry sounds scary but that’s what most of the world’s population is doing daily.
48+ Hour Fasts – These ones will make you enter into deeper autophagy and burn a ton of body fat. In my opinion, the fastest and healthiest fat loss strategy would be to cycle between 3-5 day fasts with OMAD refeeds. You want to lose the fat as fast as possible and extended fasts are the quickest way of doing it.
Alternate Day Fasting – There are also approaches like the 5:2 Diet and Alternate Day Fasting, which include fasting but allow the consumption of about 500 calories on days of abstention. The Fasting Mimicking Diet falls into the same camp. Those small number of calories are only for increasing compliance. I wouldn’t recommend this, because caloric restriction won’t allow all of the physiological benefits of fasting to kick in. You want to shock the body and go straight to zero for the greatest effects. Complete abstinence is a much more effective strategy for both your physiology and psychology. Eating something would neglect the entire idea behind fasting, which is to abstain and reset.
Dry Fasting – Not drinking liquids is also said to have autophagic benefits although there aren’t many studies putting this theory to the test. One day of dry fasting is thought to equal 3 days of water fasting. The idea is that if you deprive yourself of water, your body will start to produce its own by converting the triglycerides from the adipose tissue into metabolic water. Hydrogen gets released as a byproduct of beta-oxidation. Dry fasting has been practiced in certain religious and healing practices. In general, you don’t want to become dehydrated for too long. However, daily time-restricted dry fasting of 12-16 hours can be another thing to do if you need deeper autophagy. At your own risk, of course.

Targeted Intermittent Fasting

To overcome the challenging situation of wanting to spend more time in a fasted state while still being able to train hard I like to use targeted intermittent fasting. Here’s what it looks like:

Fast for the majority of the day as long as you can before working out.
Consume only water and zero calorie teas or coffee all the way up until 18-20 hours of fasting.
You can even add a window of dry fasting for 12-16 hours into it before introducing liquids and calories.
When starting to workout at 18-20 hours, consume a protein shake with 20-30 grams protein. You can even stay within 15-20 grams.
It’s preferable to drink it during the actual workout and use quality protein powders that don’t have artificial sweeteners or other additives.
For even greater performance you can use a bit of D-ribose, exogenous ketones, or some beta-alanine.
In the post-workout scenario eat the rest of your calories within 2-3 hours or in a single meal. Make sure you still get enough protein after training.

The limiting factor of intermittent fasting is that you won’t be able to train as hard as you potentially could. Of course, you’ll have more energy to push yourself and get stronger if you ate something before that. However, that protein supplementation minimizes the length of how long before you have to do it.

You don’t need to be consuming any calories all the way up until the point you’re about to do resistance training. At that moment, you’d want to have some protein and amino acids to protect you against excessive catabolism. The protein shake contains amino acids and other building blocks that will help with performance. Thanks to having fasted for about 18-20 hours before that, your body will utilize that protein quite rapidly and it’s not going to cause any issues. Before lifting weights, you’ll be in deep ketosis and you don’t need any exogenous nutrients to fuel your daily low-intensity activities.

Targeted Intermittent Fasting should be done only with intense resistance training that depletes muscle glycogen and damages muscle fibers. It’s not necessary for cardio, yoga, or something else like that because your body isn’t under such demanding conditions. Also, it’s not advisable to be doing TIF continuously every day throughout the year. You want to use it during periods of more physical activity and anabolism but not when prioritizing autophagy.

It doesn’t even matter how long you fast for – you can still do this type of targeted fasting and working out fasted. You simply fast all the way up until the workout, then you drink a protein shake during the workout, continue to fast until your post-workout meal, and then finish eating for the rest of the day. It’s generally best to combine TIF with OMAD because a lower eating frequency is still more beneficial. On 16/8 it’s not necessary because you haven’t been fasting for that long.

Definitely avoid the generic supplements with artificial sweeteners, colorings, and other questionable flavorings because they promote insulin resistance and gut problems. Instead, you’d want to find a quality brand with natural ingredients and zero fillers. Also, for the best anabolic effect, you’d benefit most from either whey or rice protein. Whey is more anabolic whereas rice is slightly less. Other plant-based proteins like hemp or pea are also okay but they may lack the complete amino acid profile and they may be too high in fiber. The 20-30 grams of protein in the shake is taken to reach peak muscle protein synthesis activation. On easier workouts, you can stay within 15-20 grams and gain the same effect.

Taking BCAAs in conjunction with the protein shake isn’t necessary, although not detrimental either. A quality whey protein would already have enough aminos, which makes the additional BCAAs an overkill.

Other ingredients you can add to the TIF shake include creatine, beta-alanine, cordyceps, and D-ribose. If you’re planning on having a real killer workout, then maybe taking some target keto carbs from dextrose or a banana can also be good. At that point, you simply have to know what the purpose of your training is. I myself simply stick to protein and creatine – it’s all you really need. In total, it would include about 100-150 calories, which is very low compared to the amount of work you’ll be still able to produce.

After the TIF workout, you should wait about 1-2 hours before having the post-workout meal. This will lower your cortisol and promotes proper digestion. To trigger additional MPS, you’d want to be eating complete proteins high in leucine, such as eggs. Honestly, eggs are the best post-workout muscle building food because the cholesterol is going to promote healing and the leucine will stimulate MPS. If you’d like to really build muscle, then taking 2-3 grams of leucine powder can also work. Next to that, meat, fish, and some veggies sounds like a good meal. If you’re eating carbs like potatoes or rice, then you’d want to avoid these fattier cuts of meat and eggs. Instead, combine them with lean proteins like white fish and chicken breast.

Targeted Intermittent Fasting: Fast every day for 18-20 hours, water and tea only while fasting, start working out around 18 hours, 20-30g protein during training, eat other calories post-workout, eating window of 2 hours.

You want to avoid autophagy boosting and anti-inflammatory compounds after resistance training. The reason is that they can block some of the adaptations your body’s going through. You shouldn’t take a cold shower or an ice bath after lifting weights either – they can blunt the hormetic response. Instead of taking a bunch of turmeric and medicinal herbs, you should relish more with the anabolic foods.

Honestly, the targeted intermittent fasting should be the default way of eating whatever diet you follow. Here’s why:

You want to be in a fasted state relatively often. At least with low blood sugar and ketosis
You only really need to eat if you’re doing something physical. Most of the day doesn’t require eating if you already ate within the last 24-48 hours.
You would want to have some protein before doing resistance training for performance and recovery. Taking the protein during the workout will be digested quite rapidly and it won’t even feel like you’ve fasted prior to that. It’ll also prime muscle growth faster.
You don’t need to be eating any more than once a day. Even I who’s working out almost every day can maintain physical performance and even build muscle. Most people shouldn’t eat more than twice a day but OMAD is still more optimal.
Eating at a slight caloric deficit or at least around maintenance promotes longevity. By doing TIF you’re circumventing the limiting factor on muscle performance and are still able to build muscle despite eating extra calories.

The only time you should follow a higher meal frequency would be during pregnancy, malnourishment, some medical condition, severe metabolic damage, elderhood, or when you’re doing a ton of physical exercise.

The leaner and more physically active you are, the less you need to fast. First of all, there’s not much benefit to gain from that frequent abstinence. You’ll hit a point of diminishing returns quite quickly after which there are no great advantages. Secondly, if you want to work-out and keep making progress in your exercise performance, then you simply won’t be able to do so as much. Fasting is powerful but good quality nutrition is still the foundation for getting stronger and building healthy muscle.

What I recommend is to have therapeutic water fasts that last for 3-5 days 2-4 times per year. Preferably every quarter. You should have a 48 hour fast at least once within 1-3 months and 24 hour one every 2 weeks.

You can ease into it and start with skipping breakfast at first, but in my opinion, it’s a lot better to simply shock yourself completely. This will wake your metabolism up and tells the liver that it’s time to start producing those ketone bodies.

Gastric Clearance, Linking Fasting to Sleep

Digestion takes about 5-6 hours. If you eat you won’t be in a fasted state once you stop eating.

If you stopped eating at 6pm, you won’t be in a fasted state while awake. The next morning you will be though. You really don’t want your feeding window too close to bedtime since you won’t get into a fasted state for halfway through the night. Fasting at night is related to the benefits of the glymphatic system. Clearing out metabolic waste from the brain.

Most people eat breakfast or dinner with others so you’ll have to find the time that works for you. If you have to eat at night, just try not to eat late night snacks of boost the blood glucose up too high with dessert.

Eating at around 10am-12pm and 6-8pm is less likely to intrude upon one’s lifestyle or social life, while still getting the sleep related fasting effects.

4-6 Hour Feeding Windows

Do produce a number of positive health effects: increased insulin sensitivity, decreased blood pressure, decreased oxidative stress, decreases in evening appetite. However, either no change in body weight or an increase. They overeat in those small windows.

People tend to lose or maintain weight on a one meal a day window. May not be great for performance though.

Longer-Term Fasting

5 Day

Day One/Five

The standard morning routine of meditation, cold thermogenesis, and red-light therapy. During the day I’m going to be drinking very sparingly and only when I feel thirsty.

You NEED TO Get Enough Electrolytes! Fasting with nothing but pure water will make you flush out all of the minerals in your body, which can lead to muscle cramps, lethargy, exhaustion, heart palpitations, and elevated cortisol.

Daily sodium minimum is at about 1500-2300 mg-s, which is 1-2tsp of salt. If you’re physically active or are sweating a lot, then aim for up to 3000-4000 mg-s, which is 3-4 tsp of salt. Use quality sea salt or pink rock salt. Mix it with water for better absorption.
RDA for potassium is 4700 but once you get enough sodium, you don’t have to worry about getting any more than 2500 mg-s of potassium. Sodium is potassium-sparing and your cells will lose potassium only if you lose sodium. You can use potassium salts like NuSalt to get more potassium with less sodium.
Other electrolytes like magnesium, calcium, phosphorus, and chloride aren’t that important during 3-5 day fasts because most of them are actually stored inside the body. Magnesium is much better absorbed through the skin than from supplements. That’s why taking an Epson salt bath with magnesium flakes can be a very good idea. However, 300-450 mg of magnesium can do wonders. Taking a multivitamin is necessary only if you fast for longer than 5-7 days. Your ability to absorb vitamins is much lower without food anyway so it’s easier to not take any supplements.

Additional sources of electrolytes can be baking soda and apple cider vinegar.

Baking soda is 100% sodium bicarbonate and 1 tsp of baking soda has 1259 mg of sodium. It’s great for balancing the body’s pH levels, fixing digestive issues and healing the kidneys. Baking soda is a natural antibacterial and antifungal agent that promotes alkalinity in the body. You shouldn’t take around meal times because it’ll interfere with stomach acid production.
Apple Cider Vinegar – ACV is zero calories but it has trace amounts of potassium and other minerals so it’s great to consume while fasting. During the fasting window, you should use the distilled vinegar without the mother.

That’s why I consume 1 cup of water with ½ tsp of baking soda, 1-2 tsp of ACV once or twice a day. This will also prevent kidney stones and ulcers while fasting, which may happen because of inadequate production of digestive enzymes.

Besides drinking salted water all day, you can also consume some black coffee, sparkling water, mineral water, non-caloric teas, and that’s practically it. The danger of drinking coffee or drinking too much water, in general, is that you may have to go to the bathroom more often. If you’re peeing very frequently, then you’ll also excrete out more electrolytes. A loss of minerals will make you feel more tired and actually predisposes you to dehydration. That’s why dry fasting can be much more effective than water fasting because you’ll hold onto your salts and you’ll enter into ketosis faster.

If you want to establish a ketogenic state faster, then you would want to deplete your liver glycogen stores to promote the production of ketone bodies. That’s why it’s a good idea to make your last meal before fasting low carb. By the next day, you’ll be in a semi-fasted state already with ketones running through your veins. Start the day with a long walk and you’re already there.

Some tips for surviving the first night would be to drink a small cup of water with 1 tsp of ACV before going to bed. This will reduce hunger and lowers your blood sugar in the morning.

PRO TIP: If you want to ramp up your metabolism and raise body temperature, then you can have 1/2 tsp of Cayenne pepper in your water. This will heat up your body and can stave off hunger. It won’t break a fast and the capsaicin stimulates autophagy.

Day Two – Staying Active

Once your body begins to show the first signs of ketosis, it starts to use its own stored fat for fuel, which gives plenty of energy to the brain and muscles. Your mental acuity and alertness will actually increase because of elevated cortisol and adrenaline as well.

While fasting for longer periods of time, it’s important to stay active and keep moving. You don’t want your body to start wasting away your muscle tissue just because of inactivity. It’s a good idea to either do a few sets of push-ups or use resistance bands to keep the stimulus active.

Walking is also a great way to reduce hunger. My hypothesis is that because you’ll be converting more body fat into energy, you’ll feel as if you’ve consumed some actual calories because on a metabolic level that’s exactly what happens.

How do you deal with other people cooking food around you and eating right in front of your eyes?

First, you have to realize that the reason you get the cravings to eat something is purely due to you being exposed to that particular sensory stimulation (the aroma of doughnuts, the sizzling sound of steak, the pleasurable looks of your peers enjoying their food).
Secondly, once you recognize that you’ve been tricked into craving food, then you have the opportunity to manifest your willpower. The key is to start associating more pleasure with staying indomitable and to associate pain with giving in. This way you’ll feel better about yourself if you do manage to hold your discipline.

Day Three – Things Are Starting to Get Good

My daily liquid consumption usually looks something like this:

Rinse my mouth with salt water after waking up and drink a cup of water with a pinch of sea salt.
During the day, 1 cup of water with ½ tsp of baking soda, 1-2 tsp of ACV, drank over the course of 2 hours.
When I feel thirsty, I sip on some regular water.
At noon, I drink 1-2 cups of coffee.
In the afternoon, I drink a cup of green tea with a pinch of sea salt.
If I’m feeling hungry in the evening, I’ll make a cup of decaf coffee.
In the evening, I drink a cup of water with 1 tsp of ACV and ½ tsp of sea salt.

In total, this will add up to 5-8 cups of liquids a day and about 2000-3000 mg-s of sodium, depending on the day.

It’s not actually a good idea to be drinking a lot of water while fasting because it’ll make you urinate more thus excreting more electrolytes.

The key is to pay attention to your hydration levels by monitoring the color of your urine and the context of your saliva.

If your urine is crystal clear and you’re going to the bathroom every hour, then you’re edging on the side of overhydration and should dial down your liquid consumption.
If your urine is dark yellow, brown, purple, or pure dark, then you’re very dehydrated and have to find something to drink.
If your mouth is all dry and lips cracked, then you’re starting to get dehydrated and should get a few sips of water to drink.

Dehydration can inhibit mTOR and stimulate more autophagy because the body is forced to obtain the water it needs from other cells.

There’s a difference between a soft and a hard dry fast:

Soft dry fast allows you to come into contact with water on your skin such as showering or mouth hygiene
Hard dry fast limits all contact with hydrogen whether through the air, skin care products, or fumes.

Prolonged periods of dehydration may become dangerous to your health and cause long-term damage. So, how to do it safely?

To prevent dangerous dehydration, you’d want to drink adequate amounts of water, sodium, and vegetables the day before to fill up your mineral stores.
During the day, don’t consume any liquids from water, tea, coffee, or anything else. It’d be better to avoid strenuous physical activities as well to prevent muscle cramps. You don’t want to expose yourself to too much heat either like with saunas, baths, or steam rooms.
If you’re dry fasting only during the day then you can “break the dehydration period” with a glass of salted water in the evening. Then I’d continue with more lemon juice water and apple cider vinegar.
After that, you can eat a low glycemic meal that maintains stable blood sugar levels and insulin.
If you’re dry fasting for longer than 24 hours, then you would simply go to bed without eating or drinking anything. In that case, you’d have to be cautious and take full responsibility for your decisions.
Again – do your research and prepare yourself in advance.

Day Four – Things Getting Beautiful

It can be useful to measure your blood glucose and ketones to see where you lie. Ketosis itself begins around 0.5 mmol-s and within 4 days of fasting you can expect to fall somewhere between 2.0-5.0 mmol-s. If you hit numbers above 6.0-7.0 and you’re worried about ketoacidosis, then instead of bailing halfway through go for a long walk or exercise.

The reason you register so many ketones have to do with not burning them for energy and thus keeping them in the bloodstream for longer. That’s why you also have to look at your blood glucose. Generally, less glucose entails more ketones, unless you’re border-lining ketoacidosis. If your ketones and glucose both stay high for way too long, then consider breaking the fast or consult a physician.

Being in a fasted state is a unique and profound experience. You’re not feeling particularly hungry or tired but still somewhat limited in energy. It’s a blissful state where you can enjoy the clarity of mind and heart – free from cravings, free from attachment to food or the desire to consume something mindlessly. Fasting not only resets your taste buds from the imprisonment of processed food but also liberates your mind from being dependent on certain types of food that you tend to crave the most. Even the healthy kind.

Day Five – Preparing for the One Meal to Rule Them All

If you’re already eating a very clean diet with a ton of autophagic compounds, medicinal herbs, and staying in a slight caloric deficit, then you’re already getting most of the health benefits of longer fasts.

The morning routine was the same – ACV with baking soda and water, some coffee at noon, and smalls sips of water throughout the day.

You want to start off with easily digestible liquids like hot lemon water, bone broth, and stews. After waiting about 30 minutes, you move on with some fermented foods and steamed vegetables. The first protein you’d consume should be easy on digestion like eggs or fish. Too much meat can put unwanted stress on the gut.

Day Six – The Aftermath

On day 2 of eating again, you should eat slightly above your maintenance as to nourish the body and restore its energy. A small surplus of 200 calories is more than enough to rev up your metabolism and thyroid again. What you do on day 3 of eating again depends on your body composition and goals.

If you’re overweight and have more than 20 pounds to lose, then you can immediately go for another extended fast for 3-5 days. Your body fat is food and the second fast will be that much easier.
If you’re already lean and around 10% body fat, then you can swap over to the one meal a day or warrior diet with a daily intermittent fasting window of 16-22 hours fasted. Physically very active people can adopt targeted IF. Your next extended fast of 3-5 days for longevity-boosting reasons should be in a few months.

Fasting-Mimicking Diet

Valter Longo (The Longevity Diet): Alternate-day modified fasting, which is eating minimal calories every other day for a 24-hour period. Or an extended FMD, which is the program Longo advocates, which involves consuming minimal calories for 5 consecutive days.

Completely fast for 24 hours, then eat to satiety for the following 24 hours. Better than caloric restriction at maintaining long-term weight loss and allows autophagy. 3–5-day fasts can stimulate autophagy, weight loss, and long-term reduction of IGF-1, glucose, and markers of inflammation and aging.
Low in calories and protein. Meals are 360 calories each: 9% protein, 44% fat, and 47% carbohydrates. The diet is followed for 5 consecutive days with 3 meals on the first day (1090 calories), and 2 meals on each of the next 4 days (725 calories each day).

Fasting Mimicking Diet and the Immune System

Here’s how it works:

You eat about 500-1000 calories every day
Your daily macros are low protein, moderate carb, moderate fat
You eat things like a nutbar, a bowl of soup, and some crackers with a few olives or something
Day One you eat about 1000 calories – 10% protein, 55% fat, and 35% carbs
Day 2-5 you eat about 500-700 calories – 10% protein, 45% fat, 45% carbs
Day 6 you transition back to a normal caloric intake with complex carbs, vegetables, and minimal meat, fish, and cheese

Studies on the fasting mimicking diet have shown that it lowers cholesterol, C-reactive protein, blood glucose, IGF-1, and blood pressure. However, it’s possible these effects simply came from the caloric restriction.

Fasting or a fasting-mimicking diet can improve neurodegenerative disorders by upregulating brain-derived neurotrophic factor (BDNF), which supports the growth and development of neuronal connections. The ketogenic diet has also shown to facilitate glutamate into GABA, which is important, as excess glutamate can overstimulate cells and lead to neural inflammation.

Feast-Famine Cycling

Weston Price: Native Americans cycled between the summer cultivation of starches and fruits and far greater reliance on fats from animals (particularly organ meats and marrow) during winter. 9 months of the year was limited to wild game, such as caribou and moose. During the summer, they were able to use growing plants. During the winter some use was made of bark and buds of trees.
Use fat instead of glucose during the winter months. Giving the digestive system a rest and cells a chance to engage in natural cell turnover.
Dr. Pompa’s 5-1-1 strategy: Seasonal eating with cyclic ketosis. For 5 days, follow a low-carb, ketogenic diet, or especially if you’re trying to lose weight, a calorie-restricted diet (primarily local and seasonal foods). 1 day of the week, fast for 24 hours. The remaining day of the week, have a feast day, eating any of your favorite healthy foods, especially carbohydrates, until you’re full. You could also do a 4-2-1 or a 2-2-3 as a better fat-burning approach. Bonus points if you eat seasonally, such as more carbohydrates in the warmer months and more proteins and fats in the colder months: fresh fruit and berries in the spring, tubers and squash in the fall, heavier cuts of meat and fermented foods in the winter.

General Fasting Information

How to Break a Fast

Breaking the fast with a lot of carbohydrates may cause an abrupt weight gain. The reason for that is sodium retention. While fasting you excrete a lot of water and refeeding on carbs causes antidiuresis of potassium and sodium. You’ll get bloated but you may also have an energy crash of insulin.

Therefore, you want to be eating something that’s easier to digest and doesn’t put too much strain on the gut. It also depends on how long you’ve been fasting for. If you’re coming off a 5 day fast, then you need to be more patient than you would when just doing daily intermittent fasting with 16 hours fasted.

Let’s start off with the average situation where you’ve been fasting for about 16-18 hours and you’re nearing the finish line. During your fast, you can drink non-caloric beverages like water, tea or coffee.

Now that you’re about to break the fast, you want to consume something that stimulates the digestive tract without releasing insulin.

Apple cider vinegar is perfect for this – it balances healthy pH levels, kills off bad bacteria in your gut, stabilizes blood sugar and improves overall health. You can drink a glass of apple cider vinegar during your fast. But it’s a great drink for breaking it as well. Here’s what I do before eating any meals.

2 tbsp of raw apple cider vinegar
1 half of lemon squeezed into hot water
1 pinch of cinnamon for better blood sugar stabilization
1 pinch of sea salt

Alternatively, you can do this without apple cider vinegar as well and just use hot lemon water. In any case, you want the citric acid from lemons to promote the creation of digestive enzymes in the gut before you eat. After that, you can also drink some bone broth. Bone broth is amazing and super good for you because it has a ton of electrolytes but it’s also packed with collagen.

Collagen protein is what most of your body is made of – your joints, nails, hair, skin – it helps to keep you more youthful and elastic.
Drinking bone broth after your fast will also help you to absorb the other electrolytes and minerals a lot better. Your gut has been cleaning house for a while and is now ready to utilize the nutrients from the bone broth as well as the foods you’ll be consuming afterward.

If you’ve been fasting for over 20 hours, then it’s a good idea to drink some bone broth or some soup before you eat anything solid. If you’ve fasted for just 16 hours then it’s not that important but still a good idea.

BONUS TIP: Add cinnamon to bone broth – it’s magnificent.

An alternative for bone broth is also fish broth. You cook up all the leftover bits of the fish, like the head, the fins and bones so you could get all those extra omega-3 fatty acids. Don’t just throw away these foods when there are still so many unused nutrients on them. When cooking fish, avoid boiling temperatures and overcooking because it may damage the fats. It would be best to steam the fish in some medium-heat water for many hours and make a soup out of it.

If you don’t have access to bone broth but you still want to give yourself some immediate energy without crashing, then you can also consume some MCT oil. MCTs get converted into energy faster because the fatty acids in it bypass the liver and go straight to the bloodstream.

After you’ve drunk your lemon water and maybe bone broth, then you should wait for about 15-30 minutes to let your gut absorb the nutrients. You might feel your intestines waking up, which is a good thing.

To prevent a sugar crash, I recommend your first meal should be something small and low glycemic no matter what diet you’re on. This will keep you in a semi-fasted state because of the non-existent rise in blood sugar. Some examples would be:

2-3 eggs, half an avocado, some nuts and spinach
1 can of sardines with some salad and olive oil

I wouldn’t recommend you break your fast with red meat because it’s more difficult to digest than eggs or fish. Meat products should be eaten as your second meal.

The first meal should be still relatively small. In total, it should be around 500 calories. Unless you’re coming straight from a workout. In that case, you’d want to spike muscle protein synthesis with more protein and calories.

On your second meal, you should eat based upon your desired anabolic-catabolic condition. If you’re trying to build muscle or recover from exercise, then it’s a good idea to pick something from the ModTOR group.

When in maintenance mode or wanting deeper autophagy, stick to more nTOR foods and eat primarily plant-based.

The best time to eat fruit ever is when your liver glycogen is empty i.e. when fasting or while exercising. If your liver is already full and you’re eating fruit, then that fructose will be stored as fat and you may even get fatty liver disease. Fruit for dessert isn’t a good idea.

If you do choose to consume fruit, then still make it low glycemic and opt for fruit with more fiber, like apples, berries or pears. Some citrus like grapefruit and oranges can be good as well. The high carb fruits like bananas and mangos should be considered more like performance fuel because they’re more insulinogenic.

There are some ways to trigger autophagy that you can consume while fasting:

Green tea has polyphenols and other ingredients like epigallocatechin-3-Gallate (EGCG) that stimulate autophagy. Black tea, herbal teas, and others like chamomile are also okay.
Coconut oil or MCT oil can also stimulate autophagy in very small amounts by raising ketones. However, as we found out, too much fat and too much energy in the system will raise insulin. Any more than 1 tsp will probably have a counter-balancing effect.
Medicinal Mushrooms – Reishi mushroom extracts are shown to increase autophagy and inhibit breast cancer growth as do the others like chaga and cordyceps. You can take maybe 1 tsp of reishi or chaga but not any more.
Coffee stimulates lipid metabolism through the autophagolysosomal pathway in mice. However, excess caffeine consumption may lead to higher blood glucose and insulin levels because of over-stimulating cortisol. That’s why drinking too much coffee may actually interfere with the fast. You shouldn’t drink any more than 2-4 cups a day.
Apple Cider Vinegar has trace amounts of micronutrients and bacterial residue but it most likely isn’t enough to kick you out of a fasted state. It may actually boost autophagy by promoting the cleaning process. You can use the distilled ACV during the fasting window and opt for the one with the mother when you start eating.

Can you add some artificial sweeteners to your drinks while fasting?

Aspartame doesn’t have any effect on the insulin response whether alone or combined with food. When protein produces a significant insulin response, then aspartame doesn’t seem to have any effect. However, aspartame is thought to be linked with many cancers and tumors.
Neither aspartame or saccharin seem to raise insulin. However, in one study they took people in a fasted state and made them swish 8 different taste solutions in their mouth for 45 seconds and then spit them out. Sucrose and saccharin were the only ones that activated an insulin response. However, in another study, they didn’t get the same results. Maybe the subject’s mind created their own placebo response by raising their blood sugar by will.
Direct transfusions of Acesulfame K increased insulin in rats.
Sucralose aka Splenda activates certain taste receptors that in some studies may stimulate insulin. However, one study found that infusing sucralose straight into the gut didn’t stimulate the hormones that raise insulin.
Stevia can lower postprandial insulin levels compared to aspartame and sucrose. It’s the only natural sweetener that’s fine to consume in moderation.

Even if artificial sweeteners may not spike your insulin, it doesn’t mean they can’t inhibit autophagy. They’re also shown to have a negative effect on gut microbiome so it’s better to avoid them entirely.

A single portion and one piece of gum probably has 2-5 calories. Mostly coming from sugar alcohols and carbohydrates. You would definitely want to avoid gums that have corn syrup, fructose, high fructose corn syrup, and aspartame because we know these are quite bad for your health and gut flora. Of course, if you’re only consuming like 1-2 pieces of gum with these ingredients, then you won’t have a negative side effect on your health, granted you’re eating a healthy diet.

1-2 pieces of gum won’t break a fast in most cases. Brushing your teeth once is also okay. You just have to make sure you don’t swallow the saliva, not follow it up with 2 cans of diet soda, and not stimulate insulin by starting to crave for more food.

Putting a few slices of lemon, lime, orange, cucumber, or mint leaves into your water has zero effect on your blood sugar, autophagy, or fasting. Lemons and other citrus, however, contain calories, namely fructose, which stimulates the liver in a way to break the fasted state.

If you were to eat some lemons, then you’re going to absorb the fructose, digest it, and thus inhibit the fasting. Whether or not it’s enough to break the fast completely depends on how much lemon you swallowed and how does it affect your blood sugar. I dare to say that 1-2 slices of lemon have a negligible effect on the fasted state.
If the lemon slices are simply sitting in the water, then they’re maintaining the fructose inside the cellular matrix without releasing them into the liquid (unless you squeeze them empty, of course). In that case, you’re not absorbing the fructose either, which won’t affect the fasting.

The general guideline is that just drinking lemon flavored water while fasting won’t break the fast as long as it’s not lemon juice or some sort of a sugar-filled lemon sports drink.

In medicine, Glauber’s salt is used as a mild laxative that triggers bowel movements. If you add 5-20 grams of Glauber’s salt to water, you can remove constipation, reduce bloating and clean the digestive tract. Any more than that may cause diarrhea and can lead to dehydration so don’t overconsume it.

It’s true that adding butter to your coffee will keep you in ketosis and maintains somewhat of a fasted state but it’s still going to inhibit autophagy.

If you’re doing fasting for weight loss purposes and adding butter or MCT oil to your coffee helps you to make it through the fast then go for it. However, do remember that you’ll still need to consume fewer calories and putting an entire stick of butter into your cup will give you at least a few hundred calories.
If you’re fasting to thoroughly clean your body from toxic proteins and inflammation, then I’d advise you to not consume anything at all and do strict water fasting with mineral water with these salts and teas.
If you’re sitting on a couch and drinking bulletproof coffee in the morning after having slept for 8 hours, then your body is in a state where it doesn’t need excess energy. You’ve been sedentary and there are no real energy demands on your muscles that you can’t cover with endogenous production of liver ketones. In that case, drinking that coffee will have a much bigger effect on autophagy because your homeostasis for nutrient signaling is much lower. You will get a bigger nutrient signaling effect from smaller amounts of calories because your body’s energy demands are much lower.
If you were to take that same bulletproof coffee and drink it maybe at noon time when you’ve already moved around, taken a long walk, maybe had a workout or done some chores, then it’s going to have less of an effect because your body will be under higher energy demands. In that case, your ceiling for nutrient signaling is higher because the calories you’d consume would be allocated into use much more effectively and they’ll be burnt off faster. You may still interfere with autophagy a little bit but not to the extent as you would when you drink that same coffee with the same number of calories in the morning when your body doesn’t need that much energy.

There are some calories in BCAAs although they’re used for muscle protein synthesis. One gram of BCAAs usually has about 4-5 calories and a single serving of a standard amino drink will have about 20 calories. Therefore, BCAAs will kick you out of a fasted state, but whether or not it’s a bad thing depends on many things.

BCAAs play the biggest role in supplying amino acids and energy with muscles specifically. At any given time, the liver is releasing a constant supply of amino acids to skeletal muscle for maintaining blood sugar levels and supporting cellular protein homeostasis. This mechanism is supposed to keep your cells nourished with enough building blocks needed for survival.
If you’re coming from a diet that doesn’t restrict carbohydrates and maintains a glucose-dependent metabolism, then, of course, you’re going to lose muscle tissue while fasting. That’s why you want to get into ketosis as fast as possible if you’re doing intermittent fasting. Don’t even try to fast for extended periods of time unless you’ve gotten into ketosis because you’re going to lose a whole lot of muscle. It means that if you’re in a deep fasted state with elevated level of ketones, you’re more protective of lean muscle tissue than if you were to be consuming amino acids and negating the positive effects of fasting.
Leucine and BCAAs acids do spike insulin but they increase plasma levels of insulin levels temporarily and they have almost no effect on glucose or urea nitrogen.
Working out fasted is definitely more catabolic than working out fed.
- If you’ve eaten a few hours before a workout, then you have nothing to worry about in regards to amino acids and muscle loss because your blood will be filled with BCAAs from food.
- If you’re working out fasted and not having eaten anything for over 12-16 hours, then BCAAs can have an additional protective effect.

The key is to time your BCAA intake in a way that doesn’t kick you out of a fasted state.

Taking BCAAs before a workout or when being sedentary will stop the fast and make you catabolic.
However, if you’re working out, then you’re not necessarily in ketosis anyway. Heavy exercise, especially resistance training, releases muscle glycogen into the blood, thus raising insulin and lowering concentrations of ketones. That’s why a hard workout can cause a transient loss of ketosis.

The reason you’d want to drink mineral water is that when you’re fasting, you’re flushing out a lot of water and this may lead to electrolyte imbalances and mineral deficiencies. To prevent that, you can simply add a pinch of sea salt or pink Himalayan sea salt to your water. Also, consuming ionized rock salt will give you some iodine as well, which promotes thyroid functioning and prevents hypothyroidism.

If you’re already overweight or have excess body fat, then your body is already carrying around enough energy. You don’t need to elevate your ketones after you adapt to fasting ketosis. BHB salts or other supplements aren’t a fat loss tool – they’re simply ways of increasing your blood ketones but as we found out too much energy in the system can have a counter-balancing effect.

If you’re planning to fast for 16-20 hours, then you’d want to boost autophagy with these compounds I mentioned earlier. You’d want to skip all calories and drink only some coffee, teas, and at the most take 1 tsp of MCT oil with compounds like ginger, turmeric, and ginseng. This will help you to maintain a caloric deficit while still cleaning your cells.

If you’re fasting for over 24 hours then I recommend you to stick to only coffee, apple cider vinegar, and tea because you don’t need the extra energy from fat or the herbs as your own endogenous ketone body production is through the roof.

Things to Keep in Mind

The key to a healthy and successful fast is to establish ketosis as soon as possible and to prevent your body from entering into a semi-starved state. It also means that if you’re trying to lose weight, then it would be better to avoid all calories and do strict fasting until you’re lean rather than follow a calorically restricted diet that keeps you malnourished for several months.

Fasting raises certain stress hormones in the body such as cortisol, adrenaline, and norepinephrine that will heighten your awareness and mental clarity. Chronically elevated levels of these stress hormones may promote fat gain, low thyroid, exhaustion, and adrenal fatigue. Fasting itself won’t necessarily make you stressed out or weaken your immune system. It’s always context dependent and the other lifestyle factors need to be kept in mind.

Here are a few common stressors in your life that will make fasting much worse than it is:

Being stressed out because of work makes you more prone to overeating and too much cortisol.
Not sleeping enough promotes weight gain and insulin resistance, which will negate some of the benefits of fasting.
Feeling anxiety and mental turmoil may cause the same stress as does physical pain and discomfort.
Combining too much exercise with a lot of fasting may lower your thyroid functioning and lead to many plateaus.
Poor food quality and not enough nutrients will lead to some deficiencies that make you more tired and can cause health problems.

Should You Fast with Low Thyroid?

Low thyroid functioning is most commonly caused by too much stress on the body. If there are too many stress hormones circulating the blood, you’ll lower the thyroid hormones as well as a means of self-defense.

Hypothyroidism is caused by too low amounts of thyroid hormones in the blood and it usually happens in people who’ve had Hashimoto’s disease, thyroiditis or have had their thyroid removed. Thyroid cells absorb iodine found in some foods and combine it with the amino acid tyrosine, which is used to create thyroid hormones: thyroxine (T4) and triiodothyronine (T3). They are then released into the bloodstream to affect your body temperature, your daily caloric needs, your heart rate and what’s your metabolic rate.

T3 and T4 are regulated by the hypothalamus and the pituitary gland inside your brain.

When thyroid hormones decrease, the pituitary gland releases thyroid releasing hormone (TRH) to signal the thyroid gland to produce more T3 and T4.
With high levels of T3 and T4 in the blood, the pituitary gland releases less TRH so the thyroid gland could slow down.
TSH production requires adequate protein, magnesium, and zinc.
T4 requires iodine, vitamins C, and B2
T3 requires selenium, and is dependent on healthy liver and adrenal gland function
Most of the thyroid hormones comprise of T4 – nearly 80%. T3 is the active form of T4 and it’s thought to be more potent in regulating energy metabolism. There are also T0, T1, and T2, which act as hormone precursors and byproducts.

To prevent low thyroid from fasting you want to make sure you get enough calories during your eating window. A slow metabolism isn’t the result of time restricted feeding per se but more by not giving the body adequate nutrients. If you already suffer from low thyroid and experience the symptoms of hypothyroidism, then it would be a good idea to shorten your fasting window a little bit to allow your body time to recover. Simply have your food a few hours earlier and you’ll speed up your metabolic processes.

Here’s what you can do to overcome low thyroid without medication:

Get More Iodine – The thyroid needs iodine to produce thyroid hormones. Even small doses of 250 micrograms of iodine a day can help the thyroid. You can get iodine only from diet and rich sources for that are sea vegetables, algae, wild caught fish, eggs, seaweed, shellfish, iodized salt, and some dairy.
Limit Goitrogenic Foods – Goitrogens are compounds that can affect the thyroid gland if consumed in large amounts. Foods high in goitrogens are things like cruciferous vegetables, broccoli, cabbage, kale, and some fruit. However, the benefits of these foods far outweigh the downside. They’d become a problem only if you eat too many raw vegetables. If you cook or steam them lightly then you’ll lower the number of goitrogens in them.
Tyrosine-rich foods that support the thyroid are pumpkin seeds, beef, poultry, almonds, avocados, eggs, and fish. They also have B12 and selenium. You should aim for organic meats because they’re not injected with antibiotics and other harmful hormones.
A Healthy Insulin Spike – If you eat some carbohydrates like a sweet potato or rice, then you can boost your metabolic rate.
Especially, if you’re eating a low carb diet. Prolonged periods of dieting will slow down your metabolism and doing some carb cycling can be very beneficial.
Eat More Calories – Dieting and restricting calories for too long will slow down your metabolism and thyroid functioning. Having a diet-break for a few days where you eat slightly above your maintenance can help you to boost your metabolic rate. However, you don’t want to be eating inflammatory foods like processed carbs, pastries, pizzas, or ice cream. Instead, you’d want to get more of the thyroid supporting foods we’ve talked about here.

Now for the things you don’t want to be doing if you suffer an under reactive thyroid:

Avoid All Gluten – Gluten is a common allergen that activates an autoimmune response on the thyroid. People with Hashimoto’s or hypothyroidism tend to be sensitive to gluten as well. Gluten is found everywhere – not just in bread, pasta, and cookies – it’s in almost all packaged foods, sauces, meats, skin care products, and the particles can even float around in the air.
Don’t Drink Tap Water – Most tap water contains fluorine and chlorine that inhibit iodine absorption and dampen your pineal gland’s functioning.
Limit other potential allergens as well such as dairy, nuts, shellfish, eggs, fish, soy, or meat if you are sensitive to these foods.
Don’t Fast for Too Long – It’ll lower your thyroid functioning further and can decrease metabolic rate. Definitely, you shouldn’t fast for longer than 24 hours if you have low thyroid. Until you’ve healed your thyroid and metabolism, somewhere between 16-18 hours is fine.
Reduce Your Stress – It’s going to make you feel more drained and exhausted. Don’t start exercising harder or get more stressed out about work but try to relax more and allow your adrenals to recover.
You should also avoid stimulants like coffee and sugar because they’ll activate the adrenal glands.
Avoid Environmental Toxins such as pesticides, mold, BPA found in plastics, isoflavones found in soy, potassium perchlorate, cigarette smoke, and keep your home clean from these toxins. Heat saunas and sweating can help you to eliminate these toxins from your body.

Should You Do Intermittent Fasting When Trying to Bulk

In mainstream fitness advice, it’s recommended to eat very frequently – up to 4-6 small meals a day to avoid the catabolism of fasting. However, intermittent fasting can help you to actually build muscle in many ways:

Short-term fasting has been shown to increase Luteinizing Hormone (LH), which is a precursor to testosterone. In a study done on obese men, LH increased by 67% after 56 hours.
Another study found that obese men saw a 26% increase in GNHR (Gonadotropin-releasing hormone), which is another testosterone stimulant. The same study found that men who were working out saw a 67% increase in GNHR, which led to a 180% boost in testosterone.
Occasional extended fasts increase nutrient partitioning and can help with absorption rates. Cycling your food intake is probably one of the best ways of maintaining metabolic flexibility.

A healthier body will build healthier muscles and promotes quality weight gain, not fat gain. For building muscle, you need to do resistance training, eat slightly more protein, get a small surplus of calories, sleep enough, and stay consistent. The only thing to keep in mind would be to restrict your feeding window a little bit so you would have some more time to increase protein synthesis.

When trying to build muscle, then fasted workouts aren’t ideal because they may limit your strength potential. The key to growing muscle is getting stronger and that’s why you may find the targeted intermittent fasting protocol or the 16/8 Leangains protocol perfectly suited for this. Any more frequent eating will definitely promote more anabolism but they’re not necessary.

Should Pregnant Women Fast

Whatever the case may be, the mother should focus on being as healthy as they can to promote the health of her child in the future. Quality food, stress management, enough movement, and sunlight are all essential. Fasting can be a good addition but only in a dose-specific manner and definitely not all the time. I would still recommend having a daily fast of at least 14-16 hours to promote the general health of both organisms. Then once a week you may have a 20 hour fast but definitely not any longer than that during pregnancy.

Women may react to time-restricted feeding more negatively than men because of their hormonal sensitivity. It makes sense physiologically as well because they need to be the caregivers and have to actually give birth to offspring.

Should Children Do Intermittent Fasting

A growing child needs adequate amounts of IGF-1 and mTOR to promote the proper development of skeletal muscle, bone strength, jawline, brain growth, and the right hormones. That’s why it’s even more important to make sure young kids get things like quality grass-fed meat, fish, eggs, vegetables, and even whole milk, preferably from the mother’s breast. It’s not a good idea to deprive children of these essential nutrients, especially during the most critical periods of growth.

Children already produce a lot of growth hormone, which helps them to build new tissue, muscles, and develops their brain. As you age this surge of growth begins to drop. Fasting is an amazing way to promote growth hormone production and increase longevity. But this may not be necessary for young children. However, when you look at the body composition and health of most children today then you can see a growing concern with diabetes, obesity, insulin resistance, and other problems. Fasting can cure a lot of those diseases but it’s still not going to compensate for an unhealthy lifestyle.

Children should learn how to follow their hunger more intuitively and recognize when they actually need fuel and when they’re simply craving junk food. This teaches them to be more flexible while still dipping into a fasted state.

Deliberately enforcing time-restricted feeding onto children isn’t necessary and parents should simply eliminate behaviors of snacking, binging, sedentarism, and cravings. If there’s one thing you could do to benefit your child’s future metabolic health, then it would be not teaching them to eat sugar and candy. It’s just conditioning that can be easily prevented by replacing it with only whole foods. Your kids learn their behavior from you and those around them. So, make sure you are a good role model first.

Should Old People Do Intermittent Fasting

The only problem with fasting when you’re older is that you may be more predisposed to muscle loss and catabolism. This may make you more prone to metabolic disease and more aging. As you lose muscle, you’re more predisposed to bone fractures, insulin resistance, neurodegeneration, and cardiovascular disease.

In general, the trend already shows that all the anabolic hormones like HGH and testosterone drop alongside with a reduction in lean body mass. Part of it has to do with becoming more sedentary and not doing resistance training but it’s also partly because of becoming less anabolic.

Leucine resistance, in particular, makes it more difficult for old people to maintain muscle, not to mention build it. That’s why longer periods of fasting may lead to accumulated sarcopenia. However, that can be easily alleviated by becoming more active and stronger.

To circumvent sarcopenia, you’d have to keep lifting weights, eat adequate amounts of protein, and avoid sedentarism. Increasing protein intake up to 35-40% can also be a good idea as to negate some of the leucine resistance. To stimulate MPS after exercise, you can even take 3-5 grams of leucine to promote muscle homeostasis.

It’s not recommended for old people above their 60s to have extended fasts for 3-5 days either. Going without eating for such a long time may have side-effects on muscle mass. The elderly go catabolic more easily because of low anabolic hormones. That’s why even on the daily IF schedule they should focus more on the 16/8-time frame instead of a very tight OMAD meal.

Should You Fast Every Day

If you jeopardize your metabolic rate too much, or if you cause too much stress with fasting, then you’ll end up harming your health by making yourself more predisposed to metabolic issues. Fasting may not be always good for you and sometimes it’d be better to be more anabolic i.e. eat more frequently and consume higher calories. As long as you use it to promote quality muscle growth, you’ll be improving your health. That’s why you should change up your fasting window every once in a while, by either extending your eating window a few hours, or going for a longer 3-5 day fast, and then refeeding. The idea is to cycle fasting as you do with your overall nutrition.

Additional Fasting Mistakes to Avoid:

Don’t Become Dependent of Coffee – Caffeine is an amazing appetite suppressant that helps to continue fasting. At the same time, it can turn into a powerful drug. Don’t drink any more than 1-3 cups a day and periodically cycle off from it.
Don’t Get Dehydrated – Although short dry fasting is beneficial, there’s the danger of not hydrating properly afterwards. Just drinking water may not be enough, which is why you should eat plenty of vegetables and occasional fruit to hydrate the cells better.
Don’t Neglect the Electrolytes – Insufficient sodium, potassium, and magnesium may not only cause cramping but will also raise cortisol. In fact, not getting enough salt can raise insulin and keep you in fight or flight mode. Use a bit of minerals in your water but also season the food properly.
Don’t Bring in Additional Stressors – Make sure your life doesn’t get in the way of fasting. Get enough sleep, practice meditation, don’t over-work yourself, have downtime, do something fun, spend time with family, and don’t combine long fasts with a lot of caloric restriction and exercise.
Don’t Freeze to Death – During fasting, you may feel slightly colder than normal. This is because of limited calories and lower heat production. If your fingers and toes are getting numb or blue, then you should stop and cover yourself up. Dress warmly and don’t push yourself too hard.
Don’t Fast for Too Long Too Often – Be mindful of how well you can handle fasting. Start off with daily time-restricted feeding. Then have a 24-hour fast, then a 48-hour one, and then a 3-day fast. Some signs of too much fasting are constant headaches, fatigue, feeling like being hit with a club, not sleeping well, shivering and feeling very cold despite wearing a lot of clothes.
Don’t Be Afraid of Hunger – Most people have manic fear of going hungry. It’s more psychological than physical. Fasting can actually help you to reconceptualize hunger and associate it with more vigor and success.
Don’t Make It a Big Deal – If you think that you may potentially damage yourself, then you probably will, because of creating a stress response with your mind. Choose to see it as something that empowers not harms you and you’ll start to feel amazing.
Don’t Gorge After Fasting – It doesn’t matter how long you fast if you jeopardize it all by eating excessive amounts of calories and still gaining weight. Moderation is key, especially in fasting and eating.

Feeding Deep into the Night Is Bad (In Humans)

The feeding window must fall during a period of time when the person is active (daytime). This time restricted feeding is also anchored in all the gene systems of the body and provided a more regular, stable circadian rhythm. 80% of the genes in your body are on a 24-hour schedule. Their expression is high or low at specific times. When they are expressed at the wrong times, negative health effects occur.

Light is the most important zeitgeber and food comes in second.