University of Sydney study links diet changes to lower biological age markers in four weeks

A University of Sydney study found that adults aged 65-75 who changed their diets for four weeks showed reduced biological age markers in three of four diet groups. Researchers assigned 104 participants to one of four diets. Two diets were omnivorous and two were semi-vegetarian, each pair split between high-fat and high-carbohydrate versions. All diets provided 14 percent of energy from protein.

Scientists tracked 20 biomarkers, including cholesterol and insulin levels, to calculate biological age. Biological age reflects health indicators rather than years lived. After four weeks, participants on the high-carbohydrate omnivorous diet, the high-carbohydrate semi-vegetarian diet, and the high-fat semi-vegetarian diet showed lower biological age scores.

The high-fat omnivorous group showed no meaningful change.

Andrews, who led the study, said the findings offer an early indication of potential benefits from dietary changes later in life. The team cautioned that results are preliminary and may reflect only short-term effects. The study, titled “Short-Term Dietary Intervention Alters Physiological Profiles Relevant to Ageing,” was published in Aging Cell.

Diets rich in complex carbohydrates and plant-based components produced the most pronounced improvements, according to the report.