Nutrition and Fasting
Nutrition research is noisy because most of it is observational, so the few large trials carry extra weight. In PREDIMED, 7,447 Spanish adults at high cardiovascular risk were assigned to a Mediterranean diet with extra-virgin olive oil, a Mediterranean diet with nuts, or advice to cut dietary fat. Both Mediterranean groups had fewer major cardiovascular events over a median of 4.8 years (hazard ratios 0.69 and 0.72). The results were corrected and republished in 2018 after protocol problems were found at some sites.1
For calorie restriction, the best human data come from CALERIE: healthy, non-obese adults aged 21 to 50 were asked to cut calories by 25% for two years, actually cut about 12%, lost an average of 7.5 kg, and improved LDL cholesterol, blood pressure, C-reactive protein and insulin sensitivity compared with controls.2 Fasting trends deserve the same scrutiny: in a 12-week trial of 116 adults with overweight or obesity, eating within an eight-hour window led to no more weight loss than eating three structured meals a day.3
The articles below separate what trials have shown from what cohort studies only suggest.
Reading path
Read in this order: the essentials first, then the detail, then the reviews that test popular claims.
Start here
- The Longevity Nutrition Blueprint: What to Eat, What to Avoid, and WhyThe eating patterns most strongly linked to long-term health, the foods to emphasize and limit, and why the evidence points that way.
- The Mediterranean Diet for Longevity: What the Strongest Evidence in Nutrition Science Actually ShowsWhat PREDIMED and other studies show about the Mediterranean diet and heart disease, dementia and mortality, and how to eat this way.
Go deeper
- Protein and Longevity: How Much You Actually Need and Why It Changes With AgeHow much protein adults need, why requirements rise with age, how to spread it across meals, and when lower intakes may be preferable.
- Caloric Restriction and Longevity: What 90 Years of Research Tells Us About Eating LessWhat decades of calorie-restriction research in animals and people show about aging, including the CALERIE trial, and the trade-offs involved.
- Time-Restricted Eating: A Complete Evidence Review — Benefits, Optimal Windows, and Who It's Not ForWhat time-restricted eating does to weight, blood sugar and blood pressure in human trials, how eating windows compare, and who should avoid it.
- Alcohol and Longevity: What the Evidence Actually ShowsWhat the evidence says about alcohol and lifespan, why older studies made moderate drinking look protective, and what newer research shows.
Evidence checks
- Does Fasting Actually Slow Aging?Intermittent fasting, time-restricted eating, prolonged fasting, and the fasting-mimicking diet — each has different evidence. We untangle the claims from the science and give you the real picture.
- The Ketogenic Diet and Longevity: What the Evidence Shows Beyond the HypeWhat the ketogenic diet does to metabolism, what human studies show for weight, blood sugar and lipids, and what is known about longevity.
Sources
- 1Estruch R, et al. "Primary Prevention of Cardiovascular Disease with a Mediterranean Diet Supplemented with Extra-Virgin Olive Oil or Nuts." N Engl J Med. 2018;378(25):e34. PubMed · DOI
- 2Kraus WE, et al. "2 years of calorie restriction and cardiometabolic risk (CALERIE): exploratory outcomes of a multicentre, phase 2, randomised controlled trial." Lancet Diabetes Endocrinol. 2019;7(9):673-683. PubMed · DOI
- 3Lowe DA, et al. "Effects of Time-Restricted Eating on Weight Loss and Other Metabolic Parameters in Women and Men With Overweight and Obesity: The TREAT Randomized Clinical Trial." JAMA Intern Med. 2020;180(11):1491-1499. PubMed · DOI