Mediterranean
Pattern: vegetables, fruits, whole grains, legumes, nuts, olive oil as primary fat, fish, modest poultry/eggs/dairy, minimal red meat, modest red wine. Lots of fiber, moderate protein, low refined carbs.
Strongest evidence: PREDIMED trial (n=7,447) showed ~30% reduction in major cardiovascular events vs control. Multiple cohort studies show reduced all-cause mortality. The dietary pattern with the most consistent long-term outcome data in human trials.
Limitations: Total protein is moderate; for muscle-focused adults, may need supplementation. Not particularly weight-loss optimized.
Keto
Pattern: very low carb (<30 g/day), high fat (~70%), moderate protein. Forces ketosis. Originally developed for epilepsy.
Strengths: Strong satiety effects in many people. Effective for type 2 diabetes management (lowers HbA1c rapidly). Some evidence for cognitive support in specific neurological conditions. Short-term weight loss can be substantial.
Limitations: Hard to sustain long-term, adherence drops sharply at 6+ months. May negatively affect lipids in some people (ApoB rises). Insufficient fiber if not deliberately added. Long-term outcome data is sparse. Athletic performance often degraded above moderate intensity.
High-protein
Pattern: 1.0-1.2 g protein per pound of goal weight; carbs and fat fill remaining calories. Not a diet so much as a macronutrient priority.
Strengths: Best for body composition, muscle preservation in deficits, growth in surplus. Strong satiety. Compatible with most other dietary frameworks. See protein article.
Limitations: Doesn't dictate other food choices. Without parallel attention to fiber and quality, can become protein-and-cheese-and-not-much-else.
Side-by-side
| Factor | Mediterranean | Keto | High-Protein |
|---|---|---|---|
| Cardiovascular outcomes | Strongest evidence | Mixed | Generally good |
| Weight loss (short-term) | Modest | Strong initially | Strong |
| Long-term sustainability | High | Low | High |
| Muscle preservation | Moderate | Moderate | Strongest |
| Athletic performance | Good | Mixed | Good |
| Fiber intake | High | Often low | Variable |
| Type 2 diabetes | Effective | Very effective short-term | Effective |
The hybrid that works
The framework most longevity-focused practitioners now recommend:
- Mediterranean-style food choices (vegetables, fish, olive oil, legumes, whole grains, nuts)
- High-protein emphasis (1.0+ g/lb of goal weight)
- Moderate carb (not keto, not high)
- Limited refined sugar and processed foods
- Limited alcohol
This combines the cardiovascular outcome benefits of Mediterranean with the body composition benefits of high-protein. Sustainable. Compatible with most lifestyles.
Which when
| Goal | Best fit |
|---|---|
| Cardiovascular longevity | Mediterranean (or hybrid) |
| Maximum body composition | High-protein hybrid |
| Type 2 diabetes management | Keto or low-carb |
| Sustainable long-term | Mediterranean / hybrid |
| Athletic performance | High-protein with adequate carbs |
The principle: The right diet depends on the goal. For most adults pursuing healthspan, the Mediterranean-plus-protein hybrid wins. Pure keto is for specific clinical situations.
Bottom line
Mediterranean has the strongest long-term outcome data. High-protein has the strongest body composition data. Keto has specific clinical applications. For most healthspan-focused adults, a Mediterranean-style high-protein hybrid is the answer. Pure adherence to one framework matters less than executing the principles consistently for years.