- A group of scientists recently investigated links between diet quality and biological aging.
- To gauge biological age, they used cutting-edge “epigenetic clocks.”
- They found that poorer diets, which include high amounts of fast food and processed meat but low amounts of fruit and vegetables, may contribute to accelerated biological aging, even in young adults.
The results of a new study involving 826 young adults suggest that diets high in fast food, processed red meat, and soda but low in fruits and vegetables may be linked to faster biological aging.
On the other hand, diets that include abundant fruits and vegetables and little processed red meat and sodas may be associated with slower biological aging, according to the study’s findings.
The study was published in the Journal of Clinical Nutrition.
Chronological age is the one most of us are familiar with — it’s the number of years since you were born. Biological age, however, measures how well someone is aging.
There’s no single test to assess biological aging, but the two used in the current study are:
- GrimAge: Estimates the difference between chronological and biological age to estimate the acceleration of aging and predict life span.
- DunedinPACE: Provides the pace of aging by estimating how many biological years pass per year of chronological age.
Previous research has shown that both the acceleration and pace of biological aging might help predict
Both measures rely on so-called epigenetic clocks to estimate biological age by analyzing DNA methylation, which affects gene activity.
A quick primer on epigenetics and DNA methylation
Our genetic code does not change throughout our lives. However, sections of DNA can get turned “off” or “on” for a short while or permanently: The code has not changed, but how the gene functions has changed.
These are called epigenetic changes, and they accumulate throughout an individual’s life due to many factors, including diet.
Methylation is the most common type of epigenetic change. Methylation generally switches genes “off.”
By closely examining the methylation in specific cells or tissues, epigenetic clocks can estimate biological age.
It is now well-established that following a healthy diet reduces the
As it stands, we know little about this relationship. According to the authors of the new study, scientists have investigated diet and epigenetic markers of biological age but, to date, most have focused on middle-aged or older adults.
In contrast, the latest research focuses on young adults ages 21–25 – an important age group. Chronic diet-associated conditions, like type 2 diabetes or obesity, often take decades to develop, starting in young adulthood.
The authors write that diet quality generally decreases as people move from adolescence to young adulthood. “It is important for disease prevention to investigate the link between diet and health from an early age before clinical signs of age-related diseases appear,” they explain.
Overall, the authors explain their findings like this: “In general, diets emphasizing higher consumption of fruits and vegetables and lower intakes of meat, fast food, and sugar-sweetened beverages were associated with slower biological aging.”
On the other hand, “diets low in fruits and vegetables and high in meat, fast food, and sugar-sweetened beverages were linked to faster biological aging.”
Although the effects of these diets on health do not seem out of the ordinary, it seems surprising that increased biological aging was already measurable in people in their early 20s.
Medical News Today contacted one of the study’s authors, Suvi Ravi, PhD, a postdoctoral researcher at the University of Jyväskylä in Finland. We asked whether she felt the same way.
“Actually, I was not surprised,” she told us. “The findings are consistent with studies conducted in middle-aged and older populations, as well as with the few studies that have been carried out in younger individuals.”
“There was no reason to expect that our cohort would differ from these earlier observations despite their young age,” Ravi explained.
In additional analyses, the scientists added more variables, including body mass index (BMI), total energy intake, level of physical activity, alcohol intake, and smoking.
Once these factors were in place, the relationship between dietary patterns and biological aging was less clear. This hints that regular exercise, for instance, might partially compensate for a poorer diet.
MNT contacted Benjamin Reiner, PhD, a research assistant professor in the Translational Neuroscience Section of the Department of Psychiatry at the University of Pennsylvania Perelman School of Medicine. Among other topics, he researches the genetics of feeding and obesity.
He told us that these results build on previous studies showing that “alterations in diet can alter epigenetic modifications of the genome, and subsequently alter gene expression.”
“The correlation between poor diet quality and advanced epigenetic aging agrees with the current understanding of the importance of dietary choices and these choices can have enduring effects.”
— Benjamin Reiner, PhD
Epigenetic clocks show great promise, but, as with any new technology, they may not be fully reliable yet.
We asked Reiner about some of the limitations of these tools. He explained that these clocks are “trained” on specific groups of people and that methylation patterns may differ by ethnic background.
He said that in this study, the researchers utilized the GrimAge epigenetic clock model, developed from data gathered in an American research study, to examine the effects of diet on epigenetic age in a Finnish population.
This could influence the results, and Reiner suggests “a replication study using an epigenetic model created around a population ethnically more similar to the Finnish population.”
On the question of limitations, Ravi told us that “while epigenetic clocks can provide useful estimates of biological age, their ability to predict individual aging trajectories or health outcomes remains relatively modest.”
“However, current epigenetic clocks are valuable tools for identifying biological aging, at least at the population level, and new clocks are continuously being developed to improve their accuracy,” he added.
“Yes, I do believe so,” Ravi told us when we posed the question above, “and there is also evidence to support my thoughts. Some interventional
MNT also asked Reiner whether adopting a Healthier diet could slow biological aging. He believes this is “an important area of research” now that GLP-1 receptor weight loss drugs are becoming increasingly popular.
He explained that recent
“This suggests that obesity induces an ‘epigenetic memory’ and future research into the alteration of these persistent epigenetic changes will be important for developing next-generation obesity treatments,” he told us.
The current study provides fascinating insights into the links between epigenetics and diet. But we have much to learn.
“I am interested in examining how genetic risk factors, such as those related to obesity, are associated with various lifestyle factors, including nutrition,” Ravi explained when we asked about their next steps.
“Additionally, our research group is investigating how different environmental exposures are associated with biological aging,” he added.
The science of epigenetic clocks is still in its infancy, but it shows great promise. No doubt there will be fascinating insights to come.