A diet rich in whole carbohydrates and relatively low in fat can improve indicators used to assess biological age in just four weeks. This shows an Australian study published in the scientific journal Aging Cell.
Scientists from the University of Sydney followed 104 people aged between 65 and 75. Participants were divided into four groups with different balances between fats and carbohydrates and different proportions of plant and animal protein sources.
All diets were based primarily on minimally processed foods, and carbohydrates came mainly from whole grains, legumes, fruits and vegetables.
The strongest effect was reported with the omnivorous diet with more carbohydrates and less fat. In it, about 14% of energy came from protein, 28-29% from fat and approximately 53% from complex carbohydrates.
After four weeks, participants in this group showed an average of about 3.5 years lower estimated biological age compared to the beginning of the experiment and compared to the group on an omnivorous diet with more fat.
What the participants ate
The diet did not exclude animal products. Dairy foods are present in all groups, and in both omnivorous diets, half of the protein comes from animal and half from plant sources. In semi-vegetarian diets, about 70% of the protein is plant-based.
Among the main foods in the more favorable diets are:
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whole grains and muesli;
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beans, lentils and other legumes;
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fruits and vegetables;
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nuts and seeds;
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soy products;
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dairy products;
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moderate amounts of animal protein.
“We wanted the diets to be realistic“, explains study leader Dr Caitlin Andrews from the University of Sydney. The aim was not to pit plant-based and animal-based diets against each other, but to examine how protein source and fat-to-carb ratio interacted.
How scientists measure “biological age“
The researchers are not claiming that the participants literally became a few years younger. Biological age was calculated using blood pressure and 20 biomarkers, including cholesterol, insulin and C-reactive protein, which is linked to inflammation.
Most participants lost weight, an average of about 1.8 kg over four weeks. However, according to Dr. Caitlin Andrews, weight loss alone does not explain the results, as it was also observed in the higher-fat group, in which there was no significant change in biological age.
According to Dr. Thomas Holland, a physician and researcher at Rush University in Chicago, the results are consistent with accumulating evidence on the benefits of eating more fiber, fruits, vegetables and minimally processed foods.
A similar pattern is observed in the Mediterranean diet, DASH and MIND, which emphasize plant-based foods, whole grains and unsaturated fats and limit processed meat, sweets and foods with high saturated fat. fat.
What seems more important is a wholesome eating pattern: a variety of plant-based foods, enough fiber, minimally processed foods, and limiting added sugar, refined carbohydrates, and excess saturated fat.
The authors also note the study's main limitation: the experiment lasted only four weeks. Therefore, it is not yet clear whether the observed changes in biomarkers are maintained in the long term and whether they translate into a lower risk of disease or a longer life.