Washington, Aug 26: A diet rich in fruits, vegetables and whole grains could help promote healthy cellular ageing in women, and prevent chronic diseases diabetes or cancer, a study has found. In the study published in the American Journal of Epidemiology, researchers used telomere length to measure cellular ageing. Telomeres are DNA-protein structures located on the ends of chromosomes that promote stability and protect DNA. Age is the strongest predictor of telomere length - telomeres shorten in length during each cell cycle. "The key takeaway is that following a healthy diet can help us maintain healthy cells and avoid certain chronic diseases," said Cindy Leung, an assistant professor at the University of Michigan in the US.

"Emphasis should be placed on improving the overall quality of your diet rather than emphasizing individual foods or nutrients," said Leung. However, recent studies have shown that telomeres can also be shortened due to behavioral, environmental and psychological factors. Shorter telomeres have been associated with an increased risk for heart disease, type 2 diabetes and some cancers.

Researchers examined the diets of nearly 5,000 healthy adults and how well they scored on four diet quality indices, including the Mediterranean diet, the DASH diet and two commonly used measures of diet quality. For women, higher scores on each of the indices were significantly associated with longer telomere length.

"We were surprised that the findings were consistent regardless of the diet quality index we used," Leung said. "All four diets emphasise eating plenty of fruits, vegetables, whole grains and plant-based protein and limiting consumption of sugar, sodium and red and processed meat," he said. "Overall, the findings suggest that following these guidelines is associated with longer telomere length and reduces the risk of major chronic disease," he added.

"The commonality to all of the healthy diet patterns is that they are antioxidant and anti-inflammatory diets. They create a biochemical environment favorable to telomeres," said Elissa Epel, a professor at the University of California, San Francisco in the US.

In men, the findings were in the same direction, but not statistically significant.

"We have seen some gender differences in previous nutrition and telomere studies," Leung said. "It's possible that not all foods affect telomere length equally and you need higher amounts of protective foods in order to negate the harmful effects of others. However, more research is needed to explore this further," he said.