The Nutrition Rabbit Hole

Deeper dives into specific topics, edge cases, theoretical scaffolding, and the underdiscussed research that doesn’t fit the practical pages but is worth the effort if you want to understand the field properly.

This is a working collection rather than a finished section. Posts go up as the research and writing get done. The architecture is essentially blog-format: individual essays on specific topics, each going further than the practical pages have room for.

The notes below represent topics queued for development.

If a topic here interests you and you’d like to see it developed sooner, that’s worth knowing. The order in which things get written depends partly on what’s most useful to readers.

Topics in Development

The Food Industry and Where Your Food Comes From

The structural-economic reality underneath every other nutrition conversation.

• Food conglomerate concentration: A small number of multinational corporations own the vast majority of brands you encounter on supermarket shelves. Ten companies (PepsiCo, Coca-Cola, Nestlé, Mars, Kellogg’s, Unilever, Procter & Gamble, Kraft, Johnson & Johnson, General Mills) control the substantial majority of the global packaged food supply. The illusion of choice in a supermarket aisle hides the reality that most “brands” share parent companies, share supply chains, share lobbying interests, and share research funding strategies.

Research funding from these corporations shapes which questions get asked and which don’t. Marketing budgets dwarf actual research budgets. Lobbying spending shapes dietary guidelines. The same company sells you the food that produces metabolic dysfunction and the pharmaceutical that treats it.

• The corporate capture of dietary guidelines: How the research gets translated (or not) into public policy. The Dietary Guidelines for Americans process, the substantial industry influence on the committees that produce them, and the gap between what research shows and what guidelines recommend.
• Industry-funded nutrition research: The Kearns/Glantz documentation of 1960s sugar industry payments to Harvard researchers was massive. Modern industry-funded research follows similar patterns with different products. 
• The agricultural-pharmaceutical complex: How Monsanto became Bayer, how Bayer paid out $10+ billion in glyphosate cancer settlements while still selling the product, how the same companies own seeds, pesticides, and pharmaceutical interventions for the conditions their products contribute to.

Brain Food and Neurochemistry

The dense neurochemical territory connecting what you eat to how you think.

• The Insula and food perception: How the insula integrates body state signals with food perception. The insula determines what’s going on in the body and shapes how you feel about it – anxious, excited, fearful, and satisfied. Beliefs and conscious preferences interact with these signals in ways that shape both taste perception and metabolic response.
• Dopamine pairing for reshaping food preferences: The 14-day window for shifting taste preferences through consistent pairing of new foods with dopamine-triggering foods. The mechanism, the research base (Veldhuizen, Small), and the practical applications for shifting toward foods you currently don’t enjoy.
• Sugar sensing without perception of sweetness: Gut sugar-sensing cells operate independently of taste perception. Your body craves sugary food even when you can’t taste the sweetness. The neurological pathway from gut to brain that creates craving for sugar-containing foods, regardless of conscious enjoyment.
• Eating-induced anxiety: The lateral hypothalamus and locus coeruleus prepare you for eating with norepinephrine release. Felt as excitement in healthy food relationships, as anxiety in dysfunctional ones. The connection between food anxiety and broader autonomic dysregulation.
• The amino acid threshold for satiety: We eat until our brain perceives adequate amino acid intake. Carbohydrate-only and refined food meals don’t satisfy this signal properly, explaining why eating substantial calories of refined food leaves you hungry while modest amounts of nutrient-dense food satisfy you.
• Reward prediction error and food enjoyment: Setting high expectations chemically reduces satisfaction — the steakhouse you’ve heard great things about is more likely to disappoint than the random place you walked into. Applications for managing food expectations and developing genuine enjoyment of whole foods over processed ones.
• L-Tyrosine, dopamine, and motivation: The amino acid precursor to dopamine and norepinephrine. Dietary tyrosine supports neurotransmitter synthesis; supplementation can produce acute mood and motivation effects, but with chronic disruption of dopamine pathways at high doses.
• Mucuna pruriens: Contains L-DOPA naturally. Acute dopamine effects from consumption; the historical use, the modern supplement claims, and the research on Parkinson’s applications. Why is getting dopamine from amino acid precursors through food generally better than getting it from concentrated supplements.
• Serotonin and tryptophan dynamics: Why high-carbohydrate meals support serotonin synthesis (insulin shuttles competing amino acids into muscle, leaving tryptophan with less competition for blood-brain barrier transport). The traditional carbohydrate-and-protein evening meal connection to sleep quality.
• 5-HTP risks and serotonin disruption: Why direct serotonin precursor supplementation can disrupt endogenous regulation, particularly with antidepressants (serotonin syndrome risk). The slippery slope from “natural” supplementation to pharmaceutical-like effects.
• Tryptophan and tyrosine balance: Tryptophan favors serotonin and melatonin (white meats, carbohydrates rich in these); tyrosine favors dopamine and epinephrine (red meats rich in this). Food choices have downstream effects on which neuromodulators dominate.
• Eating-induced thermogenesis differences: Greatest with amino-acid-rich foods. The metabolic boost from protein consumption versus carbohydrate or fat consumption. Implications for body composition and weight management.

Hunger Hormones and Meal Timing

The endocrine signals that shape when and how much you eat.

• Hunger as neural and hormonal control: The hypothalamus contains neurons controlling sexual behavior, hunger, sleep, body temperature, and rage. Lesions in the ventromedial hypothalamus could make you ravenous or anorexic. Some neurons promote hunger; others promote satiety. The Siamese rats research where ventromedial lesion in one twin made it obese while the other stayed lean.
• Ghrelin and meal anticipation: Ghrelin is released from the GI tract and increases the desire to eat by stimulating brain areas that drive eating. Crucially, ghrelin creates food anticipatory signals – your hunger pattern matches your eating pattern through learned response, not just physiological need. Meal timing determines hunger more than hunger determines meal timing.
• The 45-minute-per-day adjustment rule: You can shift ghrelin secretion by approximately 45 minutes per day, allowing systematic adjustment of eating windows over weeks. The practical implications for intermittent fasting, shift work eating, and travel adaptation.
• The arcuate nucleus and appetite hormones: Specific neurons release molecules that act as accelerators or brakes on appetite. POMC (proopiomelanocortin) neurons make alpha-MSH, which reduces appetite. AgRP neurons stimulate eating; when stimulated, they cause animals to eat ravenously.
• Why sunlight suppresses hunger: MSH is released from the medial pituitary in response to UV light from the eyes. This is why animals and humans naturally eat less during summer months — the light-driven MSH signal reduces appetite. Blue-blocking glasses worn during the day may interfere with this signal.
• The MSH injection story: Injecting MSH (covered in some research and grey-market peptide use) reduces appetite, produces deep tanning, and dramatically increases libido. Sometimes to damaging extents. The trade-offs and why this isn’t a clean intervention.
• CCK (cholecystokinin) and satiety: Released from the GI tract in response to fatty acids, amino acids, and sugar. Reduces hunger and slows gastric emptying. Different foods stimulate different amounts of CCK; omega-3s and CLA specifically blunt appetite.
• L-Glutamine and sugar cravings: Reduces sugar cravings through specific neural pathways. The traditional advice of a spoon of L-glutamine to manage sugar cravings; the underlying mechanism; the limitations (glutamine alone can raise blood sugar; certain cancers prefer glutamine for fuel).
• Vagus senses many things: The vagus nerve senses how full the gut is, how acidic it is, how fast the heart is beating, and how full the lungs are. Many features that inform the body how to feel get integrated through vagal pathways. The intersection with breathwork (covered in Breathwork Basics) and with eating regulation.
• Chewing, the insula, and satisfaction: The insular cortex processes interoception and gets input from the sense of touch in your mouth. Adequate chewing helps determine how much you need to eat to feel satisfied.

The Big Nutrition Debates

• The fat and cholesterol debate: The historical context of how saturated fat became demonized. The Ancel Keys Seven Countries Study methodology critique. The modern lipid subfractionation work (Krauss, Sniderman, apoB). The shift from “all LDL is bad” to particle size and oxidation. 
• Sugar demonization: Lustig’s case for fructose specifically being problematic versus the broader anti-carb framing. The sugar industry’s 1960s research suppression. The actual research on fructose metabolism. 
• Industrialized grains, gluten, and lectins: Modern wheat is genuinely different from traditional wheat. The increase in celiac disease and non-celiac gluten sensitivity timing. The lectin framework (Gundry). Traditional preparation methods that mitigate concerns. The role of glyphosate in wheat treatment.
• The weight loss caloric deficit framework: Why “calories in, calories out” is technically true but practically misleading. Hormonal effects on appetite, satiety, and fat storage that mediate caloric balance. The Kevin Hall metabolic ward research that bypasses self-report problems. Why metabolic ward studies show different things than free-living studies.
• Weight gain mechanisms: What drives weight gain in modern populations? The shift from energy balance to insulin and reward system framings. 
• Vegetables, toxins, and hormesis: The Plant Paradox-adjacent territory. Why plants produce defensive compounds. Hormesis is the idea that low-dose plant toxins produce adaptive responses that strengthen the body. 
• Ancestral wisdom around food: The Weston Price research base. Traditional dietary patterns and what they reveal about adaptive eating. Where ancestral logic is well-supported. The interaction between genuine traditional wisdom and modern romanticization of it.

Specific Research Topics

• The metabolic winter hypothesis: Winter as a state of reduced food availability historically, and the metabolic adaptations that may follow from seasonal ketosis cycles. (NIH PMC article)
• Bredesen’s KetoFLEX 12/3 framework: Dale Bredesen’s protocol from The End of Alzheimer’s, the underlying research on brain inflammation and metabolic flexibility, and the specific application to cognitive decline. (Apollo Health protocol)
• Neu5Gc and red meat: A specific molecular pattern in red meat from animals that produce Neu5Gc (which humans don’t); the inflammatory implications and the proposed mechanism for some red meat associations with disease. (FoundMyFitness coverage)
• Ultraprocessed foods and cardiovascular health: Direct research linking UPF consumption to CVD outcomes; the Kevin Hall RCT and follow-up research. (FoundMyFitness coverage)
• Olive oil cooking stability: The research showing extra-virgin olive oil maintains beneficial properties during cooking, contrary to widespread assumptions that it shouldn’t be heated. (EurekAlert source)
• Olive oil and longevity: The research linking olive oil consumption to extended life expectancy through cardiovascular and other mechanisms. (ScienceDaily coverage)
• Sugar-sweetened drinks and lipid imbalance: Direct research on how added-sugar beverages produce dyslipidemia and cardiovascular risk through mechanisms distinct from total caloric intake. (ScienceDaily coverage)
• Diet soda paired with high-glycemic food: The research showing that pairing artificial sweeteners with glucose-containing foods produces specific metabolic effects beyond either alone. The Yale Susan Swithers research and follow-up work. (Inverse coverage)
• Greater thermogenesis after breakfast versus dinner: The research showing that identical calories produce different metabolic effects depending on when consumed during the day, supporting the traditional advice to eat larger early meals and smaller later ones. (Journal of Clinical Endocrinology paper)
• Gut-to-brain circuit for sugar preference: The Sloan-Kettering research showing that specific neural circuits drive sugar preference independently of taste perception. (ScienceDaily coverage)
• Salmon roe as nutrient-dense food: The research on roe’s exceptional nutrient profile and the cultural traditions surrounding fish egg consumption. (FoundMyFitness coverage)
• Blueberries for inflammatory conditions: Specific research on anthocyanins and inflammation-related conditions. (EurekAlert coverage)
• Western diet and hippocampal appetite control: The research showing that Western dietary patterns specifically impair hippocampal function in ways that further drive overeating, creating feedback loops between diet quality and appetite regulation. (Royal Society publication)
• Soluble fiber for metabolic conditions: The research base for soluble fibre’s effects on diabetes, obesity, and cardiovascular outcomes. (AJCN paper)

The Chris Masterjohn Database Resources

Chris Masterjohn has compiled extraordinarily useful practitioner-level reference resources grounded in primary biochemistry.

• The ultimate vitamin K2 resource: comprehensive treatment of K2’s role in directing calcium, the food sources, the supplementation considerations, and the interactions with vitamin D. (Resource link)
• Glutathione foods and supplements: the body’s master antioxidant; food sources versus supplementation; and the precursors. (Resource link)
• Creatine in foods and supplements: the practical reference on dietary versus supplemental creatine; vegetarian considerations particularly. (Resource link)
• Balancing methionine and glycine in foods: comprehensive food database for the amino acid balance that affects aging and ROS production. (Resource link)
• The choline database: dietary choline sources, the variability in needs, and the genetic factors affecting choline requirements. (Resource link)
• MTHFR and methylation: the genetic variants that affect folate metabolism, the practical implications for diet and supplementation, and the population variation. (Resource link)
• Fatty liver disease starting guide: the underdiagnosed condition affecting substantial portions of modern populations; dietary and lifestyle approaches; the biochemistry that drives it. (Resource link)

Personal Self-Experimentation

• Self-experimentation methodology for nutrition: Tracking meals, timing, exercise, sleep, energy patterns, mood, and digestion over enough time to identify patterns. The basic principles of personal data collection don’t require expensive tools or sophisticated analysis.
• Continuous glucose monitoring for non-diabetics: The Levels, Nutrisense, Veri, and similar services making CGM accessible. What you learn; where it’s useful; where it produces orthosomnia-equivalent anxiety; the relationship between CGM data and broader metabolic health.
• Food diary fundamentals: Why writing down what you eat is more useful than tracking apps for most people; the practical approach to identifying patterns; the limitations of self-reported food data covered in the Archer and Ioannidis methodology critiques.
• Single-variable experimentation: Testing one variable at a time to identify what matters for your specific situation. Resistance to the temptation to change five things at once and not know which one helped.
• Subjective rating systems: Daily 1-10 ratings of energy, sleep quality, digestion, mood, and motivation. The patterns that emerge over weeks of consistent rating; how this compares to expensive measurement tools.
• Working with your physician on bloodwork: Which markers are important, how to read your own results; the gap between standard reference ranges and optimal ranges; the conditions worth screening for specifically.