Popular Diets & Their Evidence

Emphasizes vegetables, fruits, whole grains, legumes, nuts, and olive oil as the primary fat, with fish and poultry over red meat, and wine in moderation. One of the most rigorously studied diets, linked to reduced cardiovascular disease, stroke, and all-cause mortality.

Study: PREDIMED Trial (NEJM, 2018) — a 7,447-person Spanish trial showing roughly 30% fewer major cardiovascular events.

Food & recipes: Oldways — Meal Plan, Food Lists & Recipes · Harvard Nutrition Source — Diet Review

Developed by NIH researchers, DASH emphasizes fruits, vegetables, whole grains, and low-fat dairy while limiting sodium, saturated fat, and sweets to lower blood pressure. Consistently ranked among the top diets for cardiovascular health.

Study: Original DASH Trial (NEJM, 1997) — a 459-person trial showing the combination diet significantly lowered blood pressure.

Food & recipes: NHLBI — DASH Eating Plan · NHLBI — A Week With the DASH Eating Plan

Restricts the timing of food intake (e.g. a daily 16:8 window, 5:2, alternate-day) rather than what's eaten. Associated with weight loss comparable to calorie restriction, plus improvements in insulin sensitivity, blood pressure, and cholesterol — though long-term evidence is still limited.

Study: Effects of Intermittent Fasting on Health, Aging, and Disease (NEJM, 2019)

Food & recipes: Harvard Nutrition Source — Diet Review · Cleveland Clinic — Types & Schedules

A very-low-carbohydrate, high-fat diet (roughly 70–80% fat) that shifts metabolism toward ketone production. Originally developed for epilepsy, now popular for weight loss; shows short-term benefits similar to other calorie-restricted diets but no clear long-term advantage.

Study: Ketogenic Diet in Obese Patients — Systematic Review & Meta-Analysis (Nutrients, 2021)

Food & recipes: Harvard Nutrition Source — Diet Review · Mayo Clinic Diet — Healthy Keto Meal Plan

Centers on fruits, vegetables, legumes, whole grains, nuts, and seeds, excluding or minimizing animal products. Associated with lower BMI, lower rates of type 2 diabetes and heart disease, and lower all-cause mortality in large cohort studies.

Study: Vegetarian Dietary Patterns and Mortality (JAMA Internal Medicine, 2013) — a roughly 73,000-person Adventist Health Study cohort.

Food & recipes: Harvard Health — Becoming a Vegetarian · WebMD — Plant-Based Diet Tips for Beginners

Modeled on presumed hunter-gatherer eating: lean meats, fish, fruits, vegetables, nuts, and seeds, excluding grains, legumes, dairy, and processed foods. Small trials show short-term improvements in glucose tolerance, waist circumference, and cardiovascular risk factors.

Study: Paleolithic vs. Mediterranean-like Diet on Glucose Tolerance (Diabetologia, 2007)

Food & recipes: Cleveland Clinic — Paleo Diet 101 · WebMD — Paleo Diet Guide

Short for Mediterranean-DASH Intervention for Neurodegenerative Delay, created by Rush University researchers — it hybridizes Mediterranean and DASH with extra emphasis on berries and leafy greens for brain health. Associated with slower cognitive decline and reduced Alzheimer's disease risk.

Study: MIND Diet Associated with Reduced Incidence of Alzheimer's Disease (Alzheimer's & Dementia, 2015) — up to 53% lower risk with strict adherence.

Food & recipes: Rush University — MIND Diet Overview · Cleveland Clinic — The MIND Diet