# NUTRITION / What we know, what we don't Canonical URL: https://shipslides.com/d/catalog-health-nutrition Raw viewer URL: https://content.shipslides.com/d/catalog-health-nutrition/raw Category: Health Slides: 13 Updated: 2026-05-17T20:55:56.706Z Tags: catalog, health, nutrition ## Summary Field Notes / 13 slides NUTRITION What we know, what we don't. A honest survey of dietary science: macros, micros, the metabolic narrative, ultra-processed foods, the Mediterranean diet, the gut microbiome — and where the evidence runs thin. Key sections include: Carbs, fats, protein — and the calorie controversy; Vitamins & minerals: deficiencies and limits; Calories in / calories out — with caveats; Blood sugar, insulin, and the metabolic narrative; Hyper-palatable, low-satiety — the dominant culprit?; The strongest evidence base in nutrition; Emerging evidence — less than once hyped; 1.2 – 2 g/kg for active adults; The new frontier — far from fully understood; Consensus on moderation — details contested. ## Slide Outline 1. Carbs, fats, protein — and the calorie controversy 2. Vitamins & minerals: deficiencies and limits 3. Calories in / calories out — with caveats 4. Blood sugar, insulin, and the metabolic narrative 5. Hyper-palatable, low-satiety — the dominant culprit? 6. The strongest evidence base in nutrition 7. Emerging evidence — less than once hyped 8. 1.2 – 2 g/kg for active adults 9. The new frontier — far from fully understood 10. Consensus on moderation — details contested 11. Most general advice is boring — and largely correct. 12. Keep going. ## Slide Transcript ### Slide 1: Slide 1 - Field Notes / 13 slides - NUTRITION - What we know, - what we don't. - A honest survey of dietary science: macros, micros, the metabolic narrative, ultra-processed foods, the Mediterranean diet, the gut microbiome — and where the evidence runs thin. - Press → to begin · Updated 2026 ### Slide 2: Carbs, fats, protein — and the calorie controversy - 02 · Macronutrients - The three molecules that supply energy. The body burns them, builds with them, stores them. We have argued for sixty years about the ideal mix; the data keeps refusing to settle the question. - 4 kcal/g - Carbohydrates - Glucose is the brain's preferred fuel. Quality matters more than quantity: whole grains, legumes, fruit. Refined sugar and flour behave differently. - 9 kcal/g - Fats - Densest energy source. Once vilified, now rehabilitated. Saturated vs. unsaturated still matters; trans fats are unambiguous harm. - 4 kcal/g - Protein - Building blocks: muscle, enzymes, hormones. Most active adults underconsume. Plant or animal — both work if amino acids are complete. - Open question: Are all calories equivalent? Thermodynamically yes. Metabolically — satiety, hormonal response, thermic effect — almost certainly no. ### Slide 3: Vitamins & minerals: deficiencies and limits - 03 · Micronutrients - Tiny doses. Outsized consequences. The body cannot synthesize most of them — they must arrive on the plate. Deficiency causes named diseases (scurvy, rickets, beriberi). Excess can cause harm too. - Vitamin D: ~40% of US adults below sufficient. Sun, fish, fortification. - B12: critical for vegans & older adults; supplement or fortify. - Iron: common deficiency in menstruating women; complex absorption. - Iodine: the public-health victory of iodized salt. - Magnesium, potassium: chronically under-consumed in Western diets. - Essential vitamins - 15+ - Essential minerals - 90% - Of US adults below veg target - Multivitamin RCTs showing mortality benefit - Food > pills, in nearly every well-conducted trial. ### Slide 4: Calories in / calories out — with caveats - 04 · Energy balance - The first law of thermodynamics holds. But "CICO" hides what matters: how appetite, hormones, sleep, stress, gut flora, and food composition shape both sides of the equation. - ~10% - Calories burned digesting protein - ~3% - Burned digesting fat - 60-70% - TDEE from BMR (mostly involuntary) - ±15% - BMR variation between individuals - What's true: Sustained energy surplus → fat gain. Sustained deficit → loss. - What's misleading: "Just eat less" assumes appetite is a free variable. It is not. - What's missing: Food matrix, fiber, processing, timing — all alter how many calories the body actually extracts and stores. ### Slide 5: Blood sugar, insulin, and the metabolic narrative - 05 · Glycemic response - Eat carbs → blood glucose rises → insulin secreted → glucose stored. Sharp spikes followed by crashes drive hunger, energy dips, and (chronically) metabolic dysfunction. - Glycemic Index ranks foods by spike magnitude. - Glycemic Load adjusts for portion — more useful in practice. - Fiber, fat, and protein flatten the curve. - Continuous glucose monitors revealed: response is highly individual. - Type 2 diabetes is now widely framed as a disease of metabolic flexibility. - Caveat: CGM-driven "personalized nutrition" remains under-evidenced for healthy adults. ### Slide 6: Hyper-palatable, low-satiety — the dominant culprit? - 06 · Ultra-processed foods - Industrial formulations engineered for shelf life, cost, and crave. The NOVA classification calls them group 4: ingredients you don't have in your kitchen, processes you can't replicate at home. - ~58% - Of US calories from UPF - Up from ~24% in the 1970s. Children & lower-income brackets eat the most. - +508 kcal/day - Hall NIH trial (2019) - RCT: subjects fed UPF ate ~500 kcal/day more than matched whole-food diet, gained weight in 2 weeks. - ↑ risk - Observational signal - Higher UPF intake associates with cardiovascular disease, type 2 diabetes, depression, all-cause mortality. - Honest caveat: "Ultra-processed" is a fuzzy category. Whole-grain bread is technically processed. The mechanism — palatability? additives? texture? — is still being unpicked. ### Slide 7: The strongest evidence base in nutrition - 07 · Mediterranean diet - Olive oil, vegetables, legumes, nuts, fish, whole grains, modest wine, little red meat. The PREDIMED trial — despite a republished re-analysis — remains the most credible large RCT for cardiovascular protection. - 30% lower major cardiovascular events vs. low-fat control (PREDIMED). - Consistent observational benefits: stroke, cognitive decline, mortality. - Not a "diet" so much as a pattern of eating, social and seasonal. - Works across populations — though adherence outside the Mediterranean is harder than it sounds. - Daily / weekly pattern - DAILY Olive oil - DAILY Vegetables - DAILY Whole grains - DAILY Fruit, nuts - 2×/wk Fish, seafood - 2×/wk Legumes - MODERATE Wine, dairy - RARE Red meat, sweets ### Slide 8: Emerging evidence — less than once hyped - 08 · Time-restricted eating - Compress eating into an 8–10 hour window; let the rest of the day be water and coffee. Animal models showed striking metabolic benefits. In humans, the picture has cooled. - Common protocol (16:8) - Practical for many; aligns eating with daylight; may aid adherence to modest deficit. - Weight-loss benefit vs. matched-calorie - 2022 NEJM trial & meta-analyses: when calories are matched, the timing benefit largely disappears. - ↓ muscle? - Caveat for older adults - Some signals of greater lean-mass loss in long-window restrictions; protein distribution matters. - Verdict: Useful as an eating-discipline scaffold for some. Not a metabolic magic bullet. The evidence is honest about that. ### Slide 9: 1.2 – 2 g/kg for active adults - 09 · Protein - The RDA (0.8 g/kg) is a floor, not a target — designed to prevent deficiency, not optimize performance, satiety, or healthy aging. - Muscle: resistance training without adequate protein wastes the stimulus. - Satiety: highest of the macros; meals with 25-40g blunt later hunger. - Aging: sarcopenia begins in your 40s; older adults likely need more, not less. - Distribution: 3-4 doses of 25-40g works better than one big hit. - Source: animal protein has higher leucine; plant works at higher total intake. - 0.8 - RDA g/kg (floor) - 1.2–1.6 - Active adult g/kg - 1.6–2.2 - Building muscle g/kg - ~3-8% - Muscle lost / decade past 30 - For an 80kg person: ~96–176g protein/day depending on goal. ### Slide 10: The new frontier — far from fully understood - 10 · Gut microbiome - ~38 trillion bacterial cells. Hundreds of species. They digest fiber we can't, manufacture vitamins, train the immune system, talk to the brain. We are barely past cataloguing them. - ~30g - Daily fiber target - Most adults consume half. Fermentable fiber feeds short-chain fatty acid producers — arguably the single most evidenced lever. - 30+ - Plant species per week - American Gut Project signal: diversity of plants > diversity of microbes > metabolic markers. - Probiotic supplements - Some strains help specific conditions; most "general health" claims are not supported. Fermented foods (yogurt, kimchi, kefir) more reliable. - Reality check: "Personalized microbiome diets" sold by startups are running ahead of the science. We don't yet know what a "good" microbiome looks like. ### Slide 11: Consensus on moderation — details contested - 11 · Salt, sugar, alcohol - SALT - < 5g/day (WHO) - Average intake ~9g. Strong link to hypertension at the population level. The "salt skeptics" debate is real but minority. - SUGAR - < 25g added/day (WHO) - Average ~70g. Liquid sugar (soda, juice) most clearly harmful. Sugar in fruit and dairy: not the same problem. - ALCOHOL - No safe level (Lancet 2018) - The "1-2 drinks is healthy" J-curve has largely been retracted by better-controlled studies. Less is better; zero is best for cancer risk. - What we know: reducing all three reduces population disease burden. What we argue about: the precise thresholds, and how much they vary individually. ### Slide 12: Most general advice is boring — and largely correct. - 12 · The honest assessment - After all the controversies, the durable advice is unglamorous: - Eat vegetables — many, varied, often. - Eat fish a couple of times a week. - Eat whole grains, legumes, nuts; not refined. - Eat less added sugar; drink less alcohol. - Eat enough protein, especially as you age. - Cook at home. Avoid most ultra-processed things. - Sleep, move, share meals. The plate is part of a life. - "Eat food. Not too much. Mostly plants." — Michael Pollan, still hard to improve on. ### Slide 13: Keep going. - 13 · Further reading - Two starting points on YouTube — a general overview and a deep dive on the ultra-processed-food story that has reshaped recent debate. - YouTube search - Nutrition science, explained → - YouTube search - Ultra-processed food — Chris van Tulleken → - Ultra-Processed People — Chris van Tulleken (2023) - In Defense of Food — Michael Pollan (2008) - The PREDIMED Study — Estruch et al., NEJM (2018, republished) - The Hall NIH UPF Trial — Cell Metabolism (2019) - NIH Office of Dietary Supplements — ods.od.nih.gov - Examine.com — independent supplement & nutrition meta-reviews - NUTRITION / Field notes 2026 — what we know, what we don't - End of deck ## Related Decks - [Nutrition](https://shipslides.com/d/health-nutrition) - [Nutrition Science: Fueling the Human Body](https://shipslides.com/d/health-nutrition-science) - [Aging — The Mechanics of Getting Older](https://shipslides.com/d/catalog-health-aging) - [Anatomia humana — a guided tour](https://shipslides.com/d/catalog-health-anatomy)