Eating a Healthy Diet with Less Sugar May Slow Signs of Biological Aging

• A new study has linked sugar consumption with signs of biological aging.
• Researchers observed how diet and sugar affected the epigenetic age of Black and white women in midlife.
• Epigenetic age is not the same as chronological age and is indicative of how behavioral and environmental factors affect “wear and tear” on the body at a cellular level.

In one of the first studies to do so, scientists have linked dietary sugar intake to epigenetic (also referred to as biological) aging.

Excess sugar consumption is already known to increase the risk of chronic disease; now, it also appears to speed up signs of aging at a cellular level. The findings were published in the journal JAMA Network Open .

Researchers also examined the impact of a healthy diet on epigenetic markers and found the opposite effect: a higher-quality diet slowed the signs of aging.

The inverse effects also appear to be independent of one another, so diet and sugar consumption should both be evaluated in a dietary context for their effects on health and aging.

“Our findings appear to fit well with the general nutritional epidemiology literature that finds added sugars to be related to chronic diseases such as cardiometabolic conditions and cancer and related processes such as inflammation, all of which track with aging and are one manifestation of wear and tear on our bodies over time,” Dorothy Chiu, PhD, a Postdoctoral Scholar at the UCSF Osher Center for Integrative Health, and first author of the study, told Healthline.

Heidi J. Silver, PhD, RD, a Research Professor of Medicine at Vanderbilt University Medical Center who wasn’t affiliated with the study, told Healthline, “While the current studies do not show cause and effect, improving overall quality of the diet might contribute to slowing age or environmentally-related epigenetic changes.”

Sugar speeds up the body’s epigenetic “clock”

Chiu and her team investigated a cohort of 342 women in midlife. Importantly, the cohort was evenly split among Black (171) and white (171), and composed of individuals from different socioeconomic backgrounds. Prior scientific studies on diet and epigenetics have historically been limited to white individuals, making them hard to generalize to a broader population.

The participants were selected as part of the NGHS study , originally commissioned in the 1980s to study cardiovascular health in white and Black females between the ages of 9 and 19. The same group was then recruited again between 2015 and 2019 when all of the women had entered midlife — the average age being 39.

To assess the role of diet and sugar on epigenetic age, researchers first utilized a number of indices to gauge diet quality. These included the aMED Index , which scores a diet based on how closely it adheres to the Mediterranean diet , and the Alternative Healthy Eating Index .

Researchers then compared scores from these dietary indices to a novel epigenetic clock known as GrimAge2 . GrimAge2, like other epigenetic clocks, relies on interpreting DNA methylation, a natural process that affects gene expression.

“DNA methylation (DNAm) is one way genes are modified and are turned on and off. It is used as a reliable indicator of epigenetic age because these patterns in DNAm have been observed to accumulate over time and are related to biological age,” said Chiu.

Researchers anticipated that a higher quality diet would slow signs of epigenetic aging, while sugar consumption would do the opposite. They were right.

However, interestingly, the effects of a healthy diet showed a far more significant response compared to sugar intake.

“Since the authors found a stronger association with diet quality and epigenetic age, it would be wiser to focus on the overall quality of the diet. Reducing added sugars intake would be one way to improve diet quality, especially if those calories are replaced with other ways to increase diet quality,” said Silver.

What is epigenetic age?

Chiu’s research is part of a growing field known as geroscience , which seeks to understand in scientific terms how aging, disease, and biology are all related. One of the important distinctions made in the field is between chronological age and biological or epigenetic age.

When you celebrate your birthday, that’s representative of your chronological age; one year is the same amount of time for everyone. However, epigenetic age indicates the health of your body at a cellular level, and it doesn’t move at the same rate for everyone.

Epigenetics refers to the impact that behavioral and environmental factors have on the age of your body.

For example, the epigenetic age of someone who eats healthy and exercises every day may increase more slowly than someone who is sedentary and consumes high amounts of sugar.

Epigenetic changes are also reversible, which means that your behavior, diet, and exercise can affect the aging process for better or worse.

“Epigenetic age reflects modifications of our genetic material or DNA that can result in changes in our gene and protein expression,” said Chiu.

“These modifications end up turning genes on or off, which can have health implications depending on how the biological functions and physiology of our cells and systems are impacted,” she said.

The bottom line

Among a cohort of Black and white women in midlife, sugar intake and diet quality were predictors of epigenetic aging.

A healthy diet appears to slow the body’s biological “clock,” while consuming sugar does the opposite.

The role of diet in epigenetic aging is part of the growing field of geroscience, which seeks to understand scientifically how biology, diet, aging, and disease are all related.