What diet can optimize health and longevity?

Transformation of the human body from birth to old age is often described as remarkable and miraculous. The changes manifest not only in one’s outward appearance but also in what happens inside the human body. While wrinkling and sagging of the skin are some of the external evidence of ageing, some signs occur internally to mark ageing. These include slowing down metabolism and decreasing muscle mass and bone density. 

Although aging is a natural growth process, many need not fear this stage. Recent studies and advances in medicine and technology have enabled many nearing retirement to achieve a more prolonged and healthy lifespan. One of the strategies that can optimize health and longevity include modifying one’s diet. A healthy diet has been shown to improve overall health and well-being and prevent or delay the progression of long-term conditions. While a healthy diet always works best with exercise, focusing on diet first is essential in promoting longevity. 

It is well-recognized that optimal diets often depend on complex factors, including genetics, sex and age. 

Here is some evidence from published studies on diets that support longevity and optimal health and well-being:

Diets rich in complex carbohydrates, regular fish consumption and sufficient plant-based protein

In a review [1] published in the journal Cell, the lead author, Valter D Longo, explained that an “everyday normocaloric longevity diet associated with low or very low side effects and extended lifespan and healthspan is characterized by a mid to high carbohydrate and low but sufficient protein intake that is mostly plant based but includes regular consumption of pesco-vegetarian derived proteins.”

His observations are supported by animal model studies to population-based studies that involved following people for several months or years to determine the association of specific diets to the overall cause of mortality or longevity. 

Fasting-mimicking diet: how to reduce weight in 5 days

Complex carbohydrates include food that has complex chains of sugar molecules. Some examples of complex carbohydrates include the following: 

  • Whole grains. Whole grains are healthy sources of complex carbohydrates and include brown rice, oats, quinoa and barley. 
  • Vegetables. Vegetables are rich in dietary fibers, which are indigestible complex carbohydrates found in the walls of plants. Some examples of these fibers include pectin, hemicellulose, cellulose, algal polysaccharides, mucilages and gums. Some examples of vegetables rich in complex carbohydrates include the following:
    • Sweet potatoes
    • Green beans
    • Carrots
    • Broccoli
    • Asparagus 
  • Legumes. Legumes form part of the Fabaceae family with the edible seeds of these plants known as pulse. Some examples of legumes are the following: 
    • Lentils 
    • Peas
    • Beans
  • Fruits. Fruits are high in complex carbohydrates and are essential components of a healthy diet that can promote longevity. Some of these fruits include the following: 
    • Apples
    • Oranges
    • Kiwi
    • Berries 
  • Regular fish consumption 

Regular fish consumption is another vital component of a healthy diet that promotes longevity. 

A meta-analysis [2] published in the European Journal of Clinical Nutrition reports that consuming fish at least twice a week compared with never eating fish reduces the risk of all-cause mortality from major chronic diseases. The findings are significant since 12 prospective cohort studies were pooled to determine the frequency and amount of fish needed in the diet to achieve longer and healthier lifespans. Eating at least 60 grams of fish per day or 420 grams weekly could reduce mortality and increase longevity. 

The study, led by L-G Zhao from the Shanghai Cancer Institute and Shanghai Jiao Tong University School of Medicine, suggested that fish consumption is linked to reduced risk for all-cause mortality. 

  • Plant-based Protein 

A systematic review published in the British Medical Journal in 2020 [3] examined the results of 32 prospective studies that investigated the association between the intake of plant and animal proteins and the risk of cancer, cardiovascular mortality and all-cause mortality. Pooled analysis of the results of the 32 studies revealed a significant association between intake of plant protein and lower risk of cardiovascular disease mortality and lower risk of all-cause mortality, but not cancer mortality. 

Dose-response analysis showed a significant inverse dose-response association between all-cause mortality and intake of plant protein. The higher the plant protein intake, the lower the risk of dying from cardiovascular disease and other long-term conditions. 

The 32 studies recruited 715,000 people, strengthening the representativeness of the research findings. The researchers also reported that when at least 3% of the body’s total energy needed daily is taken from plant proteins, there is a 5% risk reduction for premature death. 

A second study [4] published by JAMA Internal Medicine in 2020 also demonstrated similar results. The study, headed by Jiaqui Huang, Department of Health and Human Services, Bethesda, Maryland, analyzed a prospective study that followed 179,068 women and 237,036 men enrolled in the US National Institutes of Health- AARP Diet and Health Study from 1995 to 2011. 

The findings of the prospective study showed that a greater intake of plant proteins was associated with reduced overall mortality for both men and women. Shifting just 3% of the energy from animal protein (dairy products, fish, poultry, meat) to plant protein was associated with a 10% decrease in all-cause mortality or death from any cause in all participants. 

Notably, the study authors also found that replacing red meat and eggs with plant protein reduced death risk by as much as 21% in women and 24% in men- especially amongst individuals with a high intake of dietary products such as eggs or red meat. 

The findings of these studies strongly suggest that plant-based diet proteins would promote longevity while processed and red meat intake would shorten life. 

Fasting-mimicking diet: how to reduce weight in 5 days

Intermittent fasting 

Apart from diet, the review by Valter Longo [1] also showed that intermittent fasting is associated with a longer lifespan and longevity. Periodic and intermittent fasting are beginning to emerge as safe strategies that can influence healthspan and longevity by acting on disease risk factors and cellular ageing while causing minor or no side effects. 

Intermittent fasting lasting from twelve to forty-eight hours and repeated every one to seven days, while periodic fasting lasting from two to seven days and repeated every month or less can potentially treat and prevent disease and promote healthspan and longevity. However, the exact mechanisms of how these two types of fasting delay cellular ageing still need to be fully understood. 

Longevity diet 

Analyzing nutrition and diet from multiple studies, from animal studies to epidemiological and clinical research trials, researchers have found that the ideal diet for longevity should include the following: 

  • Limited white meat
  • No processed or red meat 
  • Intake of complex carbohydrates
  • Low-refined carbohydrates and low sugar 
  • 30% of calories should come from olive oil, nuts oil and other vegetable fats
  • Vegetarian diet or a whole grain-rich pescatarian and legume diet
  • Plant-based protein diet 
  • Intermittent fasting of at least 1-7 days with 12 hours interval between food intake 
  • Prolonged fasting at least once a month

Keeping body mass index (BMI) under 25 would be necessary to increase longevity. Further, maintaining ideal lean body mass and age-specific body fat levels would help add more years to your life. 

However, diets should be adapted according to individual needs. For example, older adults need sufficient protein, mainly from fish and meat resources. There may need to be more than plant-based protein diets to address the protein needs of older adults. Eating appropriate protein in the diet is necessary for presenting malnutrition in older adults. 

High consumption of complex carbohydrates amongst older adults without obesity or insulin resistance would provide the needed energy without activating the glucose signalling pathways. 

Period fasting in adults between 18 to 70 years old could reverse insulin resistance from a high-calorie diet. Notably, periodic fasting could also reduce total cholesterol, address inflammation and regulate blood pressure. 

Another study [5] published in the PLoS Medicine Journal reported that changing typical western diets rich in processed and red meats to plant-based diets rich in nuts, whole grains and legumes is linked to an eight-year longer life expectancy if followed or started at age 60. 

Although the studies showed that a plant-based protein diet, intermittent fasting, complex carbohydrates and fish consumption are associated with longevity, it is still best to consult your doctor when switching to these diets. 

Tailoring a diet according to age, sex and genetic makeup would be necessary to optimize nutrition and health. Consulting your doctor or dietician is essential to ensure that the new diet is sustainable and meets the required calories and nutrients needed by the body. 

Good nutrition is critical in overall health and wellness. Better food is associated with longevity and could reduce the risk of long-term diseases across all ages. Hence, it is essential to talk to your healthcare specialist to ensure that you are fasting correctly and taking the appropriate amounts of protein, carbohydrates and nutrients in your body. 

Finally, longevity and a healthy lifespan are all within reach. Begin your journey by eating the right kinds of food and tailoring your diet according to your nutritional needs, age, gender and genetic makeup. Each person has unique dietary needs and characteristics. Attempting to follow a one-size-fits-all approach to diet and nutrition could not be sustainable and may not lead to longevity. 

[1] https://www.cell.com/cell/fulltext/S0092-8674(22)00398-1 
[2] https://pubmed.ncbi.nlm.nih.gov/25969396/ 
[3] https://www.bmj.com/content/370/bmj.m2412
[4] https://pubmed.ncbi.nlm.nih.gov/32658243/ 
[5] https://journals.plos.org/plosmedicine/article?id=10.1371/journal.pmed.1003889 

Photograph: dasha11/Envato
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