The longevity diet is a set of guidelines for healthy eating developed by biochemist Valter Longo, Ph.D., director of the USC Longevity Institute at the USC Leonard Davis School of Gerontology, and is meant to help people live longer, healthier lives. The longevity diet recommends following a plant-based diet that includes little-to-no meat and poultry and periodic fasting. Although the diet was designed for older adults, it has potential health payoffs for people of every age and stage of life.

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Benefits

The main tenets of the longevity diet—eating more plants, less protein, and fasting—are based on Dr. Longo's research of long-lived populations around the world, including in Greece, Italy, and Japan, as well as studies he was involved in in the United States.

One of these, published in October 2016 in JAMA Internal Medicine, assessed the dietary habits and health of more than 130,000 health care professionals.

It found that "high animal protein intake was positively associated with cardiovascular mortality and high plant protein intake was inversely associated with all-cause and cardiovascular mortality, especially among individuals with at least 1 lifestyle risk factor. Substitution of plant protein for animal protein, especially that from processed red meat, was associated with lower mortality, suggesting the importance of protein source.

Dr. Longo's research also uncovered significant benefits of fasting-mimicking diets (similar to intermittent fasting)—specifically that such diets improve factors that have a significant impact on health, particularly as people age, including body mass index (BMI), blood pressure, and levels of glucose (sugar) in the blood. 

How It Works

The longevity diet resembles a modified vegan diet in which certain seafood and small amounts of meat and dairy are allowed. It is as much a lifestyle as an eating plan and can be followed for an indefinite amount of time. The guidelines include following a five-day fasting-mimicking diet periodically throughout the year. 

What to Eat

Compliant Foods

• Vegetables

   

• Fruits

• Nuts

• Olive oil

• Low-mercury seafood

• Beans

Non-Compliant Foods

• Meat (in excess)

   

• Processed sugar

• Saturated fats

• Dairy (in excess)

The majority of foods comprising the longevity diet food list are plant-based, including:

• Leafy greens like chard, spinach
• Fiber-rich vegetables
• Fresh fruits of all kinds
• Beans and legumes (chickpeas and lentils)
• Nuts

Low-mercury seafood includes shrimp, salmon, and tilapia.

The longevity diet advises avoiding meat, poultry, and dairy products, as these foods are high in saturated fat. If completely cutting out meat and poultry isn't do-able, the recommendation is to limit them as much as possible by including them in small quantities to add flavor to plant-based dishes rather making them the centerpiece of meals.

In regards to dairy: For those who must have milk and cheese, the longevity diet recommends switching from cow's milk and cheeses to goat's milk, cheeses, and yogurt, which are rich in minerals and have anti-inflammatory benefits.

Recommended Timing

For purposes of meal-planning, people who are overweight or tend to put on pounds easily are advised to eat two meals—breakfast and either lunch or dinner—and two low-sugar snacks per day. Those who are at a healthy weight or who lose weight easily are advised to eat three meals a day and one low-sugar snack.

All meals and snacks should be taken within a 10-to-12 hour time frame—for example, between 8 a.m. and 6 p.m. to 8 p.m. The guidelines also suggest not eating during the three to four hours before bedtime.

People who adhere to the longevity diet also follow an eating plan that mimics fasting several times a year. This involves consuming limited amounts of foods, mainly vegetables, nuts, and seeds, for five days. Total calories for each day range from 800 to 1100, with 60% of calories from fats, 10% from protein, and 30% from carbohydrates.

Cooking Tips

There are no hard-and-fast rules regarding food preparation on the longevity diet, although it's best to use low-fat cooking methods such as steaming, grilling, and sauteeing rather than frying.

Olive oil, which is used liberally in the Mediterranean countries where many of the tenets of the longevity diet originate, is a staple.3 High in omega-3s, it's also a versatile cooking oil that works well as a dressing, marinade, and even in some baked goods.

Considerations

For people under 65, the longevity diet recommends limiting protein intake to between 0.31 grams to 0.36 grams per pound of body weight. Older adults may eat slightly more than that, including animal protein, in order to help preserve muscle mass.

Dietary Restrictions

Virtually anyone can safely follow the food guidelines of the longevity diet, with the exception of those who might be sensitive or allergic to nuts or any other compliant food.

However, women who are pregnant or breastfeeding, as well as people who have diabetes, should not do the fasting part of the plan.

The longevity diet is more a framework for lifelong healthy eating habits than a calorie-restrictive weight loss plan. By focusing on plant-based foods, it has built-in nutritional advantages as vegetables, beans, legumes, and nuts are rich in a wide variety of vitamins, minerals, and micronutrients. When prepared in healthy ways, these foods also are lower in saturated fat and calories than the meats, poultry, and dairy products the guidelines advise limiting or, better yet, eliminating altogether. And while it may seem daunting to follow a fasting-mimicking diet for five days, it's only recommended to do this a few times a year, which for the sake of living a longer, more vibrant life may well be worth it.