Do vegetarian diets help us to live longer?

Is meat responsible for some of the illnesses we develop as we get older and are vegetarian diets the answer?

It’s no big mystery that healthy living involves eating well.

A long-standing debate has been ongoing on the effect of consuming meat and how it is supposedly harmful to our health. So, do vegetarian diets help us in our quest for longevity?

What is a vegetarian diet?

Vegetarianism falls under plant-based diets and other types like Vegan, Pescatarian and Flexitarian. Practitioners of these vegetarianism don’t consume meat and fish, although they may still eat dairy, eggs and honey. Vegetarians who eat eggs and dairy are specifically called Lacto-Ovo vegetarians.

Individuals usually adopt a vegetarian diet for personal reasons such as religion or ethical sensibilities like animal rights. Some decide to become vegetarian for environmental causes, as livestock production raises greenhouse gas emissions, contributing to climate change [1].

Do vegetarians live longer?

Though does vegetarianism help you to live longer? There is proof that vegetarianism can prolong life, at least according to a study revealing that they live six to nine years longer, which is a considerable effect [2]. 

However, there are some crucial issues to consider; vegetarians are also more likely to exercise, be married, consume less alcohol and smoke less – factors that contribute to a longer life. The causal connection between becoming vegetarian and living longer is unclear and is undoubtedly more minor than the correlation suggests.

Does eating meat affect longevity?

For over 50 years, associations between meat-eating and illness have been circumstantial and controversial [3]. The link between meat intake and unfavourable health issues has limited proof to reinforce this hypothesis. It also relies on epidemiologic connections instead of clinical trials, which indicate a cause-and-effect relation.

The link between meat intake and unfavourable health issues has limited proof to reinforce this hypothesis.

Before the practice of agriculture from 11 to 9000 years ago, human ancestors could not grow, harvest and store most plant-based products as the staple food. Plant foods are primarily accessible in certain seasons of the year. Otherwise, animals and some insects could be consistently available to nourish humans with meat as a staple food.

Then comes influences and inclusion of caloric intake, obesity and urbanisation, among other factors, which were statistically controlled. The study found that results could prove inaccurate with the non-inclusion of meat intake into nutrition science for forecasting human life expectancy.

What is the longevity diet?

So which diet should we follow? There’s the Longevity diet, which founder Dr Valter Longo, a USC Leonard Davis School of Gerontology Professor, has new research data showing a way towards a longer and healthier life.

The study uses data from hundreds of examinations looking into the connection between nutrition and longevity.

It considers epigenetics (lifestyle, genetics and a combination of both), which defines our health and lifespan. Modifying the quantity, type and timing of what we consume can be effortless and the most practical lifestyle transformation we can make to improve our health.

According to Professor Longo, the ideal longevity diet contains a proportion of:             

  • An average to increased intake of simple carbohydrates (containing legumes, vegetables, legumes and whole grains)
  • Lower protein intake from primarily plant-based origins
  • Sufficient plant-based fats to supply about 30% of energy requirements

In reality, it would look like this: 

  • Plenty of whole grains, legumes and vegetables
  • Adequate levels of nuts, olive oil and dark chocolate
  • Some fish
  • Low white meat, refined grains and sugar
  • No red meat or processed meat

The study suggests a pesco-vegetarian diet and primarily plant-based protein and fat consumption. Following the longevity diet suggests an ideal 12-13 hour window to consume meals.

Longo is also the founder of the well-known fasting mimicking diet (FMD) and advises doing five days of FMD every few months to support weight loss and longevity. The study saw that fasting could decrease inflammation, blood pressure, insulin resistance and other risk factors for metabolic disease.

Longo emphasises that the longevity diet should be tailored to serve each individual based on their profile (age, gender, health status and other factors). Especially for people over 65, who are more at risk of deficiency, sarcopenia and other conditions resulting from decreased bone and muscle mass. 

He also suggests making small, sustainable changes to your diet rather than huge differences that you can’t stick to, which could cause fluctuating weight gain and mayhem to your metabolism.

What are the latest studies on vegetarian diets and longevity?

Significantly, plant-based diets are associated with better health but not necessarily lower mortality rates [4]. The exact mechanisms of health promotion by vegan diets are still not completely clear but most likely multifactorial. Motivations for and quality of the vegan diet should be assessed in longevity studies.

According to a new study, a young adult could add more than a decade to their life expectancy by modifying their diet [5]. The key is to follow the suggested items mentioned in the longevity diet. For older people, the projected gains in life expectancy from such dietary modifications would be more minor but still significant.

Analyses are still limited, but one thing’s certain: lean towards healthy choices. A balanced vegetarian diet including nutritious foods like healthy fats, grains, plant-based proteins, and produce may offer benefits, but it carries the threat of nutritional deficiencies if inadequately designed [6].


The information included in this article is for informational purposes only. The purpose of this webpage is to promote broad consumer understanding and knowledge of various health topics. It is not intended to be a substitute for professional medical advice, diagnosis or treatment. Always seek the advice of your physician or other qualified health care provider with any questions you may have regarding a medical condition or treatment and before undertaking a new health care regimen, and never disregard professional medical advice or delay in seeking it because of something you have read on this website.