A large-scale study conducted in Germany has found that adherence to various healthy eating patterns is associated with slower biological aging.
Researchers from the German Center for Neurodegenerative Diseases (DZNE) analyzed data from 7,504 individuals and determined that those who more closely followed different healthy nutritional models generally showed more positive indicators of biological aging.
The study, published in the journal Nature Communications, utilized DNA methylation—molecular changes used to assess biological aging—to examine approximately 850,000 DNA regions. By employing three different epigenetic aging measures, known as epigenetic clocks, the researchers evaluated how dietary habits relate to cellular wear and tear.
The research examined 10 different nutritional metrics to identify links to aging. The models evaluated included the Mediterranean diet, the Nordic diet, the DASH diet (designed to stop hypertension), and the MIND diet (a combination of Mediterranean and DASH diets aimed at brain health).
Other assessed models included the Alternative Healthy Eating Index (AHEI-2010), the EAT-Lancet diet, the Plant of Dietary Index (PDI), the healthy Plant of Dietary Index (hPDI), and the unhealthy Plant of Dietary Index (uPDI). The researchers also looked at the Dietary Inflammatory Index (DII).
While different diets may offer specific advantages for areas such as heart or brain health, the findings revealed that more than 70% of the biological pathways related to cellular structure, intercellular signaling mechanisms, and metabolism were shared across the various healthy models.
“The effects are not huge, but they are at a measurable level and important for the prevention of diseases,” said Monique Breteler, an epidemiologist at DZNE. She added that slowing the aging process could reduce the risk of age-related conditions such as dementia or cardiovascular disease. “This is a promising finding because healthy eating can be shaped according to personal and cultural preferences, budget, and taste.”
The research shows there is no single mandatory diet for healthy aging. The study found that participants did not need to follow every rule of a specific diet perfectly to see benefits.
The study said that very few participants achieved high health scores across all examined dietary models. This suggests that adopting even just one of these healthy eating patterns may be sufficient to help reduce the risk of biological age outpacing chronological age. Common beneficial habits identified across the models include diversifying fruit and vegetable consumption, increasing intake of whole grains, and regularly consuming legumes such as lentils, chickpeas, and beans.
The researchers emphasized that this was an observational study, meaning it identifies a relationship between diet and aging but does not prove that healthy eating directly causes a slowing of biological aging. The results do not suggest that any diet can stop aging or extend lifespan, nor do they imply that positive biological markers mean a person's actual age is being reversed.
The analysis was primarily based on 6,470 participants aged 30 and older from the Rhineland Study in Bonn, with findings further validated by a 1,034-person group from the EPIC-Potsdam study.
The researchers also noted a specific finding regarding smokers: while the link between diet and aging was strongest in this group, smokers were not eating healthier than non-smokers. The biological reasons for this observation remain unknown. The study also clarified that healthy eating does not negate the harmful effects of smoking.