In 4 Weeks You Can “Rejuvenate” the Body: Scientists Show the Effect of a Simple Dietary Change

The study involved 104 people aged 65–75. They were divided into three groups, each of which followed a specific diet for 4 weeks. Scientists measured a wide range of biomarkers: inflammation, metabolism, kidney and liver function, blood sugar levels, and other indicators.

The results were surprising. In all groups, biological markers became “younger.” The most pronounced effect was observed among participants who followed a low-fat, high-carbohydrate diet with moderate protein content. Diets higher in plant-based protein also showed good results.

An important point: improvements were also seen in participants with prediabetes and type 2 diabetes. The low-fat, high-carbohydrate diet was based on whole foods — vegetables, fruits, whole grains, and legumes. Thanks to high fiber content and reduced fat intake, insulin sensitivity improved and glucose levels stabilized.

“We have shown that even short-term dietary changes in older adults can significantly improve physiological indicators associated with aging,” the authors noted.

The changes were comprehensive: systemic inflammation decreased, kidney and liver function improved, and metabolic markers normalized. Overall, participants’ biological age decreased by an average of 2–3 years in just 4 weeks.

For now, this is a relatively small study. The authors acknowledge that it is necessary to determine whether the effect will persist in the long term. Nevertheless, the results look promising: simple and accessible dietary changes may become an effective tool for healthy aging.

Sources: Caitlin J. Andrews, Rosilene V. Ribeiro, Alison Gosby et al. Short‐Term Dietary Intervention Alters Physiological Profiles Relevant to Ageing. Aging Cell, 2026. https://doi.org/10.1111/acel.70507