THE CONNECTION BETWEEN DIET AND LONGEVITY: Vegetarianism is Good — But Not for Too Long!

Photo source: wired.com

How can you stop aging? Scientists have long discovered that one of the most effective ways is to follow a specific diet. Everything matters here — the quantity, quality, and selection of foods. The challenge is that dietary habits have a significant but indirect impact on lifespan rather than a direct one. For instance, this occurs through epigenetic mechanisms. To explore this, American scientists conducted a study on twins.

GENOME AND EPIGENOME

e all know the immense importance DNA holds for our body’s condition. It acts as a kind of «roadmap» that guides the body’s formation and development throughout life. However, DNA is not the only factor influencing our development.

The environment, for instance, plays a significant role as well. It has an incredible number of ways to affect gene expression. Epigenetics — a branch of genetics that studies how our behavior and external environment influence gene activity — examines these mechanisms.

Thus, at the molecular level, scientists distinguish between the genome — the primary DNA sequence — and the epigenome, which refers to secondary, non-heritable changes in the genome, including so-called chemical «marks.»

METHYLATION AND PLANT-BASED DIETS

Methylation is one of the most effective epigenetic mechanisms. It is a biological process where methyl groups (tags) attach to cytosine — a nitrogenous organic compound in the DNA macromolecule. Starting in early childhood, methylation often continues to make itself known well into adulthood.

Some scientists, for example, believe that it could explain why the effects of childhood traumas manifest much later in life. But what influences methylation itself? Numerous factors influence it, with diet being one of the most significant. This is why the relationship between dietary habits and methylation has become a focal point of scientific inquiry.

However, most studies have compared «standard» dietary patterns. A team of American scientists, led by researchers from Stanford University, decided to delve into the epigenetic properties of plant-based diets. Interestingly, despite the millions of adherents to vegetarian diets, science has not known much about their epigenetic effects.

TWINS DIVIDED INTO VEGANS AND OMNIVORES

The scientists published an article detailing the results and methodology of their experiment in the peer-reviewed medical journal BMC Medicine. The two-month randomized study initially involved 22 pairs of identical twins. However, one pair withdrew from the experiment, leaving data from 21 pairs for analysis.

All participants were healthy and over 18 years old (with an average age of 40 years). Additionally, 77.3% of the participants were female. The researchers divided the twin pairs into two groups: one group followed a vegetarian diet, while the other remained omnivorous.

During the first half of the experiment, participants were provided with pre-planned menus, and in the second half, they prepared their meals while adhering to the scientists’ recommendations. Throughout the two months, participants were surveyed and submitted information through a specialized app.

UNPRECEDENTEDLY DETAILED MONITORING

The American scientists used all the modern technical tools available to analyze the data. Their approach was so meticulous that they even determined the biological age of the participants’ major organs. The immune system was evaluated separately.

They also assessed the risks of developing serious diseases, such as type 2 diabetes. Blood samples were taken from the twins three times: at the beginning, in the middle, and at the end of the experiment.

This was done to measure telomere length, calculate biological age using epigenetic clocks, and determine the level of DNA methylation. Such detailed monitoring allowed the researchers to closely track the changes in the body associated with vegetarian and omnivorous diets.

VEGANS AGE SLOWER

The scientists found that the vegan twins indeed experienced slower epigenetic aging, which had already been suggested in previous scientific literature on this diet. The slowdown in aging processes was recorded by epigenetic clocks, which were calibrated to different clinical and phenotypic markers.

Additionally, the vegan twins showed changes in their blood. They had lower levels of inflammatory biomarkers and improved indicators related to potential dysfunctions in the heart, liver, metabolic, and endocrine systems.

Unlike their omnivorous counterparts, the vegan twins also lost weight more quickly. On average, they lost 2 kg more than those in the omnivorous group.

VEGAN LONGEVITY COMES AT A PRICE!

However, the benefits of a vegan diet come with a catch. The authors of the study did indeed confirm the positive effects of switching to a plant-based diet. Unfortunately, these effects proved to be short-lived. While the diet produced remarkable results in the short term, it could lead to problems in the long run.

The issue is that vegans gradually develop nutrient deficiencies, which may not impact health immediately but can become problematic over the years. For example, if the deficiency of vitamin B12—abundant in meat, dairy, and seafood — is not addressed in time, it can lead to severe nervous system disorders.

Observations of vegans also showed that they not only lose weight but also decrease their bone density. Additionally, over time, weight loss occurs at the expense of muscle mass, which vegans also begin to lose as they age.

MANAGING METHYLATION — A PATH TO LONGEVITY?

These studies have only confirmed the preliminary findings of an earlier study published in November 2023. Nutritionists believe that the reason for healthier methylation in vegans lies in the body’s response to weight loss.

These studies open up new possibilities for scientists to manage DNA methylation. However, complete control over these processes remains purely theoretical for now.

The data on vegans may be a reaction to their increased consumption of plant-based foods, meaning it may not be directly related to longevity. Further research is needed to answer these and other questions.

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