Nutrition

Diet pattern matters more than any individual macro, micro, or "superfood." The most consistently validated dietary patterns for longevity — Mediterranean, MIND, DASH — share a common core: lots of plants, fish, nuts, legumes, olive oil; minimal ultra-processed food, sugar-sweetened beverages, and processed/red meat.

Nuance matters too: protein adequacy in midlife protects muscle and bone, which conflicts in some interpretations with the "low protein for longevity" mTOR narrative. Fasting helps glycemic control but does not outperform continuous calorie restriction for weight or lifespan in human RCTs.

What the evidence actually supports

Strong:

• Mediterranean diet pattern reduces major CVD events ~30% (PREDIMED, NEJM 2018, n=7,447) and lowers all-cause mortality across multiple cohorts. The combination of olive oil, nuts, fish, legumes, and vegetables is the most robust dietary intervention in longevity science.
• MIND diet (Mediterranean + DASH hybrid emphasizing leafy greens and berries) — Morris et al. 2015 found ~53% lower Alzheimer's risk in the highest-adherence tertile.
• Sugar-sweetened beverages raise CVD, T2D, and all-cause mortality risk in dose-response fashion.
• Processed meat is IARC Group 1 carcinogen; unprocessed red meat is Group 2A. Both have measurable colorectal cancer and CVD signals.
• Adequate dietary protein in older adults preserves muscle mass, reduces sarcopenia, and improves recovery from illness/surgery.

Moderate:

• Time-restricted eating with an early eating window (last meal before 17:00–19:00) improves fasting insulin and body composition more than late eating, even when calories are matched.
• Fasting and continuous calorie restriction produce similar weight loss and metabolic improvements long-term (Cochrane 2026; BMJ 2025 network meta-analysis n=6,582).
• High polyphenol intake (berries, olive oil, dark chocolate, tea, herbs) — observational signal for vascular and cognitive outcomes; mechanism plausible.
• GLP-1 receptor agonists (semaglutide / tirzepatide) — for adults with overweight/obesity or cardiometabolic risk: durable double-digit weight loss, 20% MACE reduction, and the first drug class to measurably slow validated epigenetic aging clocks. The catch: muscle and bone loss without aggressive protein and resistance training. See GLP-1 receptor agonists.

Weak / preliminary:

• "Optimal" macronutrient ratios — wide ranges are compatible with longevity if the food quality is high.
• Many specific superfoods (turmeric, açaí, etc.) have animal/mechanistic data without robust human RCTs.

Topics covered in depth

Dietary patterns: Mediterranean, MIND, DASH, Blue Zones →

The strongest evidence base in nutrition. What they have in common, what's different, and which to follow.

Protein, mTOR, and AMPK →

The longevity-vs-strength tension. Why blanket "low protein extends life" advice misreads the evidence in midlife and older adults. Cyclical eating patterns and timing.

Fasting and time-restricted eating →

Intermittent fasting, alternate-day, fasting-mimicking diets. What they do, what they don't, and the early-vs-late TRE evidence.

Metabolic flexibility →

The capacity to switch fuels (glucose ↔ fat). What it is, why it matters, and how to train it.

Ultra-processed food →

The single largest harm signal in modern nutrition science. NOVA classification, mortality data, the 2025 UCL trial that isolated processing from nutrients, gut and inflammation mechanisms, and how to spot UPF on a label.

Foods to limit or avoid →

Sugar, red and processed meat, industrial seed oils, alcohol — what the evidence says and what's overstated. (For ultra-processed food specifically, see the dedicated article above.)

Sweeteners →

Added sugar accelerates biological aging; "diet" sweeteners are not biologically inert; sugar alcohols (erythritol, xylitol) carry a real cardiovascular signal. Where monk fruit, allulose, and raw honey actually fit.

Practical nutrition principles (evidence-weighted)

1. Default to a Mediterranean pattern. Vegetables, legumes, fish, nuts, olive oil, whole grains, fruit. Optional moderate dairy (yogurt, cheese), modest poultry. This is the single most-evidenced dietary intervention.
2. Eat fish 2+ times/week (especially fatty fish: salmon, sardines, mackerel) or take EPA+DHA omega-3 if not.
3. Hit protein targets. ~1.2–1.6 g/kg/day for active midlife adults; older adults probably benefit from upper end. Distribute across meals (~30–40 g per meal).
4. Limit added sugar to <10% of calories (WHO) or <25 g/day (AHA for women).
5. Limit ultra-processed food (full article). The clearest dose-response signal in modern nutrition; each 10% increase in UPF energy associates with ~10% higher all-cause mortality. The 2025 UCL randomised feeding trial confirmed processing harms persist even when calories and nutrients are matched.
6. Limit red meat to 1–3 servings/week; minimize processed meat. Replace with fish, legumes, poultry.
7. Eat fiber — 25–35 g/day. Strongest single nutrient signal for cardiovascular and colorectal cancer prevention.
8. Front-load eating. Larger breakfast/lunch, lighter dinner, last meal 2–3 hours before bed. Aligns with circadian biology.
9. Don't smoke; drink minimally; hydrate adequately.

What's overhyped

• Carnivore, ketogenic, and zero-carb diets for general longevity — short-term metabolic improvements in some populations; long-term outcomes data are absent or unfavorable.
• "Detoxes" and cleanses — no clinical evidence for benefit; the liver and kidneys handle this.
• Specific superfoods marketed for individual health claims — diversity beats specialization.
• Most "anti-inflammatory diet" supplement protocols — anti-inflammatory eating works through the pattern, not concentrated extracts.

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