In recent years, the concept of "biological age" has become one of the hottest topics in the world of health and longevity. Expensive tests, innovative supplements, and complex dietary programs promise to slow the pace of aging. However, a new study suggests that the key to better metabolic health may be much simpler: The quality of our daily diet.
The study, which was recently published, examined the relationship between diet quality and biomarkers related to metabolic aging and chronic inflammation in the body.
The researchers analyzed data from 15,314 adults from the United States as part of the National Health and Nutrition Examination Survey (NHANES), collected over 15 years. To ensure that the findings were not unique to just one population, an additional cohort of 833 adults from China was also examined.
Diet quality was assessed using the HEI–2015 index, which evaluates how well eating habits align with accepted dietary guidelines. Higher scores indicate a greater consumption of dietary fiber, vitamins, minerals, and healthy fats, alongside a lower intake of sugar, processed carbohydrates, and trans fats.
The surprising link between diet and aging
The researchers examined two key markers:
Insulin resistance – one of the primary markers for the development of type 2 diabetes.
A cardiometabolic risk index linked to blood lipid levels and heart health.
The findings were clear: People who consumed a higher quality diet exhibited lower levels of insulin resistance and a healthier metabolic profile. Furthermore, a near–linear relationship was found: The better the diet quality, the better the metabolic markers.
One of the interesting findings in the study was the link between a high quality diet and a reduction in chronic inflammation.
The researchers found that the systemic immune–inflammation index (SII) explained part of the connection between a healthy diet and slower metabolic aging.
According to them, a high quality diet may reduce inflammation through:
Consumption of fiber that nourishes good gut bacteria.
Eating foods rich in polyphenols and antioxidants.
Intake of omega–3 fatty acids.
Reduction of oxidative stress in the body.
Chronic inflammation is currently considered one of the primary factors linked to aging, heart disease, diabetes, and other metabolic diseases.
So what should you eat?
The researchers emphasize that this is not about a single food or a new "superfood," but rather about consistent eating habits over time.
The diet found to be associated with better metabolic health included:
Whole grains such as oats, quinoa, and brown rice.
Vegetables of all kinds, especially green vegetables and legumes.
Fresh fruits.
Fish, poultry, and plant–based proteins.
Olive oil, nuts, seeds, and avocados.
Reduction of processed foods, sugary drinks, and pastries made from white flour.
In addition, foods rich in polyphenols such as berries, green tea, olive oil, and dark chocolate have previously been linked to anti–inflammatory effects that may contribute to metabolic health.