Since more than 40% of Americans are living with obesity today, according to the CDC, experts continue to look into the effects of the disease on the body. They've found that carrying around extra weight has significant impacts on your health, overall lifespan, and how quickly your body is aging.
In fact, according to a new study published March 18 in the journal Nutrients, researchers found that obesity can fast-track your biological aging—aka the decline in physiological function and structural integrity at the molecular and cellular level—by over 4 years. This can increase the risk of chronic diseases and an earlier death, but the researchers also found that one diet in particular can reverse this type of aging by a whopping 6 years. Let's unpack the study's findings and what this means for you.
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How Obesity Accelerates Aging
In the new study, researchers in Spain used three different epigenetic clock models to determine the biological age of 28 obese (BMI of 30 or more) and 20 average-weight participants.
They found that the obese group had an increased biological age of 4.4 years, which was consistent for both men and women. Meanwhile, the average weight group had a decreased biological age of 3.1 years.
This suggests that obesity plays a significant role in how quickly the body loses function and integrity over time, which can lead to more health issues and a shorter lifespan, the study authors wrote.
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Why The Keto Diet May Reverse These Effects
To take their research a step further, the study authors hypothesized that a specific diet intervention could help reverse biological aging in people living with obesity.
So, they put 10 obese participants on a very low-calorie ketogenic diet (VLCKD) for 180 days.
"There is a lot of evidence supporting the effectiveness and safety of [the ketogenic diet] for the treatment of obesity and its associated comorbidities since, in addition to achieving significant weight loss, it also improves cardiometabolic profiles," the study authors wrote.
However, a very low-calorie ketogenic diet is intense: it requires eating less than 800 calories a day, limiting carbs to less than 50 grams, and keeping protein intake high at around 1-1.5 grams per pound of body weight.
For these reasons, experts say VLCKD is a restrictive diet and should only be followed under the strict supervision of a healthcare professional or registered dietitian. It should also be a short-term diet and since nutrient deficiencies can occur, additional supplements should be considered.
That said, the 10 study participants who were following VLCKD for six months experienced major results.
After just one month, their biological age had dropped by an average of 6.1 years. At the six-month mark, the reduction remained at 6.2 years.
These improvements were seen in both men and women, and all participants also lost body weight: About 20 pounds within the first 30 days and 44 pounds by the end of the experiment.
"Notably, this is the first study to highlight a possible relationship between adherence to a VLCKD and the reversal of biological aging in patients with obesity," the study authors concluded. "Taken together, our study underscores the potential of nutritional strategies like VLCKD to counteract the impact of obesity on epigenetic aging."
What This Means for You
The researchers believe the keto diet works to reverse biological aging in obese people because of its ability to create nutritional ketosis, a state in which the body burns fat for fuel instead of carbs.
It also helped to reduce participants' BMI while improving several metabolic health markers, such as glucose, insulin, cholesterol, and triglycerides.
Interestingly, other methods of weight loss do not pose the same benefits. For instance, the researchers compared their results to previous studies involving women who had undergone bariatric surgery and found that the procedure did not have an effect on biological aging.
So, could following the keto diet be the key to aging backward for you, regardless of what you weigh?
Experts are hesitant to make that statement.
As Mir Ali, MD, a board-certified general surgeon, bariatric surgeon, and medical director of MemorialCare Surgical Weight Loss Center at Orange Coast Medical Center in Fountain Valley, California, told Medical News Today: "A very low-calorie ketogenic diet does show benefits, but any weight loss leading to a patient achieving a healthy weight has been shown to improve all medical conditions and prolong the life span; it is difficult to definitively conclude that the type of diet is independent of the weight loss."
Others also raised concerns about the extremeness of VLCKD, and how eating less than 800 calories a day isn't suitable for everyone.
Finally, the study authors even admitted that their research was conducted with a small group of people, so bigger and more long-term trials are needed to confirm their findings.
If you're considering adopting a keto diet for weight loss or anti-aging benefits, it's crucial to talk to your doctor first.
But, you can start focusing on eating a balanced, nutrient dense diet that's full of whole foods, like fruits, vegetables, nuts, seeds, and plenty of protein from lean meats and fish. Not only are these similar foods from the keto diet that can help you lose weight, but they also provide essential vitamins and minerals to slow the aging process.
Add this healthy eating method to getting plenty of physical activity, and you'll have a proven strategy to age slower—both inside and out.
