The search for a fountain of youth has intrigued Americans ever since Ponce De Leon came ashore looking for it in Florida in the sixteenth century. In the years since, pills, elixirs, and even severely restricting calories are just some of the ways people have sought to stave off death. Scientists have long understood that what truly lengthens your life and keeps your later years healthy are the basics we’ve known about for ages: Eat a healthy diet filled with vegetables, exercise regularly, invest in healthy relationships, reduce stress, and get enough sleep, for example. Now a team of researchers has uncovered a potential key reason these actions are so beneficial: they influence our genes.
By: Meryl Davids Landau
In a small pilot study published in the journal Aging in April 2021, when 18 midlife men strictly followed a healthy lifestyle regimen (that included following a healthy diet, sleep, exercise and relaxation guidance, and supplemental probiotics and phytonutrients) for eight weeks, their estimated biological age dropped the equivalent of about 3 years when compared with the control group that didn’t follow the regimen. (Your chronological age is determined by your birthday; researchers use biological age to measure how old our bodies appear to be based on how well we function at a genetic level. For this study, the researchers used a validated saliva test to look at changes in the participants genes to record their estimated biological age.)“This is exciting, because aging is the biggest risk factor for chronic diseases. If we can slow down [the biological effects of] aging a little bit, our quality of life can improve considerably,” says Kara Fitzgerald, ND, a functional medicine physician in Newtown, Connecticut, and the lead author of the study.
“The demonstration of interventions to slow or even reverse aging has massive implications for improving human health,” says Morgan Levine, PhD, assistant professor of pathology at the Yale School of Medicine in New Haven, Connecticut, and a member of the Yale Center for Research on Aging, who was not involved with the study.
Scientists have long understood that certain lifestyle factors make us healthy, but this study is unique because it’s one of the first randomized controlled trials — albeit a small one — to measure the collective effects of these interventions on a crucial marker of biological age: a person’s DNA.
How Our Behaviors Affect Our Genes — and Lifespans
When scientists first created a map of our genes in 2003, they hoped to uncover single genes that caused the diseases that limit our lives, like cancer or heart disease. Instead, they found that the answer was more complex. “A whole host of genes have to come together to influence these and other diseases,” Dr. Fitzgerald says.
This led to an effort to understand not just the genes that influence disease and health, but the factors that make them turn on or off, a field that’s become known as epigenetics.
They discovered that a key way that genes do this is with molecules known as methyl groups, which exist in the millions all over the body. Remove methyl groups from strands of DNA and you activate that gene. Add methyl groups and you deactivate it. When it comes to healthy aging, it’s especially important that genes that can cause problems (like those linked to inflammation or cancer) are deactivated.
So how do your behaviors influence how methyl groups are interacting with your genes?
Nutrition turns out to be an important way of affecting this methylation, as summarized in a review from the International Journal of Molecular Science in November 2018. This was also demonstrated in a mouse model study published in Molecular and Cellular Biology in 2003, where pregnant mice with a gene that makes them obese and makes their fur yellow were given nutrients that promote methylation. The gene causing the weight and color was tamped down so much that their babies were born thinner and browner.
“This was a big deal, showing how profoundly you can alter your gene expression with diet,” Fitzgerald says. Research reported in a review published in 2019 in the British Journal of Pharmacology revealed the mechanisms that make this true for people, also.
Similarly, there’s some evidence other lifestyle habits, like exercise, relaxation practices, and sleep, can all affect methylation — and thus whether our body shows signs of accelerated biological aging, Fitzgerald and her coauthors note in the paper.
For this study, the researchers asked people to strictly follow their lifestyle plan to see how it affected their biological aging compared with others following their usual routines.
DNA Clocks Determine Your Biological Age
To measure longevity from a study lasting only eight weeks, the researchers used a tool known as a DNA clock, which measures the methyl groups in many genes. The tool was discovered by a researcher at the University of California, Los Angeles who published a paper in Genome Biology in 2013. It measures a person’s biological age based on levels of methylation found on genes known to be related to aging.
The age clock used in the study (the Horvath DNAmAge calculator) uses saliva to test this. Other clocks, including those invented more recently known as second-generation age clocks, may use blood and measure a wider array of aging indicators.
For the study, the researchers took 43 healthy adult males and randomized them into two groups, one of which followed the lifestyle program. The intervention group spent a week being educated about all the various factors, then adhered to the plan for the next two months, with regular coaching throughout. Four of the people gave up during the study and were not included in the final evaluation.
Samples of saliva were conducted initially, a week after completion, and in the middle of the study. People following the researchers’ lifestyle intervention turned out to score an average of 1.96 years younger at the end than they did at the beginning according to the age clock measurements, while the control group scored an average of 1.27 years older — a 3 year difference.
What Did the Healthy Lifestyle Intervention Look Like?
The diet regimen recommended in the pilot study was chock full of vegetables: 7 cups a day, with 2 of them dark leafy greens and 2 of them cruciferous veggies like broccoli and cabbage. Participants also downed one or two beets every day, a vegetable known to help with the methylation cycle.
Healthy animal proteins, like liver, eggs, and 6 ounces of grass-fed, hormone-free meat, were part of the diet, as were good fats like olive oil and nut seed butters. Simple carbohydrates were severely restricted.
Also included were foods known to boost methylation, such as blueberries, garlic, green tea, and the herb rosemary.
Supplements were kept to a minimum — just a probiotic and a proprietary green powder called PhytoGanix (a combination of organic vegetables, fruits, seeds, herbs, plant enzymes, prebiotics and probiotics) from Metagenics, who funded the study — both because the researchers wanted to study nutrition from food and because they were concerned that over-boosting methylation might inadvertently turbocharge genes that cause cancer, Fitzgerald says.
Ron MacKenzie was one of the study participants. He’s a 54-year-old agritourism entrepreneur in Portland, Oregon. As an expert in agriculture with a girlfriend who’s a nutritionist, he’d already been eating a healthy diet before he enrolled in the study. But still he had to make many changes, especially at breakfast.
Rather than having a bowl of quinoa, breakfast became huge heaping of rainbow chard served with liver or eggs. Dinner was often a big salad to work in all the cups of vegetables required, topped with a protein like salmon.
“Food preparation took a lot of time,” he says. To help, he often put together weekday meals on weekends.
The work was worth it, MacKenzie says. He felt so energetic that even though the study is over he continues to follow it. “If I hadn’t been improving my diet, I would not feel as invigorated as I do,” he says.
Stress, sleep, and exercise also influence DNA methylation, so they were also part of the study.
Participants in the intervention group were asked to sleep seven hours or more each night, practice breathing exercises twice a day, and do moderate intensity exercises at least 30 minutes a day for five days a week.
More Research Is Needed
This is a small pilot study involving just a few dozen people (including the control group), so more research is needed to confirm these results, Fitzgerald says.
The additional studies will also need to be more diverse. Only men (mostly white and highly educated) were included, because women in the target age range of 50 to 72 would be in various states of menopause, which requires much larger numbers to tease out hormonal effects, Fitzgerald says.
In the meantime, she hopes people will adopt at least some of these lifestyle interventions. They’re already known to be healthy. And if the results of this study hold up, they just might make you younger.