Biology & Concepts 6 topics · 87 claims

insulin resistance causes hyperandrogenism

insulin resistance causes hyperandrogenism

Is high Lp(a) an actual cause of heart disease, and can new drugs lower it?

Genetics (Mendelian randomization) and large epidemiology show Lp(a) is causally atherogenic — likely more potent per particle than LDL — and siRNA/antisense/oral agents now cut it up to ~80-99%, though cardiovascular-outcome trials are still pending.

lipoprotein(a) causes cardiovascular disease

Does stress drive real, measurable inflammation?

Yes — psychological stress measurably raises inflammatory markers (IL-6, CRP) via a well-characterised glucocorticoid-resistance pathway, robustly shown in stress and PTSD meta-analyses.

chronic psychological stress causes systemic inflammation

low-FODMAP diet treats irritable bowel syndrome

low-FODMAP diet treats irritable bowel syndrome

Does poor oral health / gum disease increase dementia risk?

Yes as an association — multiple meta-analyses link gum disease and tooth loss to higher dementia risk, with a plausible mechanism (P. gingivalis in Alzheimer brains); whether it's causal is still contested, and the strongest link is with SEVERE oral disease.

poor oral health increases dementia risk

Does early-life trauma permanently raise adult inflammation?

Yes — childhood trauma is associated with elevated adult inflammatory markers decades later (meta-analysis + birth-cohort data), though the effect is modest and not found in every cohort.

childhood adversity increases lifelong inflammation

Does moderate exercise fail to reliably increase hunger in most people?

Largely true — acute exercise doesn't reliably raise hunger or food intake and often briefly suppresses it, though a subset of people do compensate by eating more, so 'never' is too strong.

exercise does not reliably increase appetite

Is the genetic heritability of brain diseases low, leaving a large lifestyle role?

Mostly not — this holds only for depression (~30-40% heritable). Schizophrenia, bipolar disorder and Alzheimer's are highly heritable (60-80%), so a blanket 'brain disease heritability is low' overgeneralises from his depression/twin work.

genetic heritability of brain diseases is low

Does diet matter far more than exercise for losing body weight (Israetel's ~80/20)?

Yes — for losing weight, diet is the dominant lever: exercise burns fewer calories than people expect and is easily out-eaten, so his ~80/20 framing is well supported (exercise still matters for health and for keeping weight off).

diet outweighs exercise for weight loss

Does the body offset heavy exercise by burning fewer calories elsewhere?

Genuinely contested — Pontzer's data show the body partly compensates for heavy exercise by burning less elsewhere (~30% offset), but two 2025-26 studies (Howard, Yegian) found total energy expenditure rises roughly linearly with activity and no real 'constraint', so the strong version isn't settled.

high exercise volume induces compensatory reduction in total energy expenditure

Does an oral bile acid boost the gut hormone GLP-1 in people?

Probably yes for the bile acid itself, but whether ordinary diet can do the same is unproven.

oral bile acid (CDCA) increases GLP-1

combined oral contraceptive decreases hyperandrogenism

combined oral contraceptive decreases hyperandrogenism

Is the post-workout 'anabolic window' only marginally important?

Yes — the 'anabolic window' is largely a myth: when total daily protein is adequate, timing it tightly around the workout makes little measurable difference to muscle or strength.

post-workout protein timing has marginal effect on muscle growth

Does talk therapy measurably reduce inflammation?

Yes, modestly — meta-analyses of dozens of RCTs find psychological therapies produce small but real reductions in inflammatory markers like IL-6 and CRP; effects are inconsistent in some settings.

psychotherapy decreases inflammatory markers

Do sugar "crashes" cause anxiety, irritability, or low mood in healthy people?

Genuinely split: one controlled-feeding trial found a high-glycemic-load diet worsened mood and fatigue, supporting a link, but the best causal test shows the hunger-mood effect is mediated by conscious perception of hunger and a large meta-analysis finds no 'sugar rush,' so the crash-drives-mood claim in healthy people is unresolved.

post-spike glucose crashes causes mood disturbance in healthy people

peppermint oil treats irritable bowel syndrome

peppermint oil treats irritable bowel syndrome

Does saving carbs for last lower your blood-sugar spike?

Yes, eating veg, protein and fat first blunts the spike, though fibre and fat drive part of it.

carbohydrate-last meal order decreases postprandial glucose

Does propionate, a fibre by-product made in the gut, make you burn more fat?

Yes in human trials, but the cleanest studies used a delivered form, so fibre-derived amounts are less certain.

colonic propionate increases fat oxidation

inositol decreases insulin resistance

inositol decreases insulin resistance

Does spreading protein across several meals build more muscle?

Weaker than stated — there's a mechanistic per-meal threshold and some observational support in older adults, but the best RCTs find little muscle advantage to spreading protein once total daily intake is adequate, so it's a minor factor at most.

protein distribution across meals improves muscle protein synthesis and lean mass

Does gaining muscle only slightly increase calories burned at rest?

Mostly yes — skeletal muscle has a low resting metabolic rate, so gaining muscle raises daily calorie burn only modestly; the effect is real but small, not the metabolic furnace it's often sold as.

added muscle mass minimally raises resting metabolic rate

Do gut problems often precede Parkinson's by years, spreading to the brain via the vagus nerve?

Leans yes — strong epidemiology shows GI problems (constipation) often precede Parkinson's by years, and animal models show gut alpha-synuclein can travel up the vagus nerve, but genetic (Mendelian-randomization) and primate data disagree, so gut-to-brain causation isn't proven.

gut dysfunction precedes Parkinson's disease

Can gut bacteria break down your appetite-suppressing hormone GLP-1?

Yes — the mechanism is consistent, but shown mostly in mice; the human contribution is unmeasured.

microbiota-derived DPP-4-like activity degrades active GLP-1

joint hypermobility increases irritable bowel syndrome

joint hypermobility increases irritable bowel syndrome

Do people born with a broken APOC3 gene get less heart disease?

Yes — independent human-genetics studies show APOC3 loss-of-function carriers have lifelong low triglycerides/remnants and markedly lower coronary risk, and one null variant is enriched in long-lived people.

APOC3 loss-of-function variants decreases cardiovascular risk independent of LDL (via remnant/triglyceride lowering)

Can food proteins block DPP-4, the enzyme that breaks down the blood-sugar hormone GLP-1?

Yes, but only shown in the lab and animals so far, and not yet proven in bread or people.

food-derived peptides inhibits DPP-4

Do gut-bacteria bile acids boost your appetite-suppressing hormone GLP-1?

Yes as a mechanism, but only shown in animals so far — human evidence is correlational.

secondary bile acids stimulates GLP-1

Does LDL enter the artery wall mainly by active transport (transcytosis) through the vessel lining?

Animal and cell evidence shows LDL crosses the artery's endothelial lining mainly by active receptor-mediated transcytosis (SR-B1/DOCK4, ALK1, caveolae), and inflammation/insulin signals can ramp this entry up.

LDL particle enters via receptor-mediated transcytosis

Does the gut bile-acid sensor FXR turn down the appetite-suppressing hormone GLP-1?

Yes — but only shown in animals and the lab so far.

intestinal FXR activation suppresses GLP-1

Does gut inflammation blunt the appetite/blood-sugar hormone GLP-1?

Probably modestly yes — inflammation seems to dampen the hormone's signal, but this is shown mainly in animals and the lab.

metabolic endotoxemia (LPS) causes GLP-1 resistance

ileal nutrient delivery increases GLP-1 secretion

ileal nutrient delivery increases GLP-1 secretion

Can indole, a gut-bacteria compound, boost the blood-sugar hormone GLP-1?

Yes, but shown mainly in animals and lab models, not yet proven in people.

microbial indole increases GLP-1

Can butyrate, a fat made when gut bacteria ferment fibre, make your body burn more calories?

Yes, but only shown in mice so far, not yet proven in people.

butyrate induces white-adipose browning and energy expenditure

Does the probiotic L. paracasei boost the appetite-and-blood-sugar hormone GLP-1?

Unclear — evidence is mixed; the main trial found no effect on the hormone, appetite, or blood sugar.

Lactobacillus paracasei W8 increases GLP-1

Does blood-sugar "variability" on a CGM predict heart disease in healthy people?

Variability tracks surrogate risk markers, but direct hard-outcome CV evidence in non-diabetics is limited, so the "predicts CVD" claim is not established.

glucose variability predicts cardiovascular risk in non-diabetics

Can gut-bacteria tryptophan compounds grow more of the cells that make the blood-sugar hormone GLP-1?

Yes, shown in human gut mini-organs and rodents, but more cells isn't a proven real-world effect.

microbial tryptophan metabolites increases enteroendocrine L-cell differentiation

gut microbiome causes insulin resistance

gut microbiome causes insulin resistance

microbial tryptophan catabolites activate intestinal AhR

microbial tryptophan catabolites activate intestinal AhR

oleanolic acid activates TGR5

oleanolic acid activates TGR5

riboflavin decreases homocysteine

riboflavin decreases homocysteine

Does high insulin block the brain's fullness signal and cause the obesity epidemic?

Insulin-leptin crosstalk in the hypothalamus is real and bidirectional in cell/animal models, but the claim that this single mechanism causally drives population-level obesity is unproven extrapolation — it is one contributing pathway, not the demonstrated master switch.

chronically elevated insulin inhibits hypothalamic leptin signaling causing perceived starvation and driving obesity

Does D-lactate made by gut bacteria worsen blood sugar control?

In obese mice, microbe-made D-lactate raised blood glucose and trapping it improved glucose, insulin and fatty-liver disease, but this is animal-stage evidence not yet shown in humans.

gut-microbiota-derived D-lactate worsens glucose metabolism

FFAR2 activation increases L-cell GLP-1 secretion

FFAR2 activation increases L-cell GLP-1 secretion

IMMP decreases postprandial glucose

IMMP decreases postprandial glucose

levan decreases postprandial glucose

levan decreases postprandial glucose