The Mediterranean diet has long been praised for its ability to promote health and longevity. Studies have shown that individuals who follow this diet – rich in plant-based foods and fish, while reducing their consumption of red meat and dairy – tend to be healthier in terms of their heart health, cancer risk, diabetes, dementia, and overall mortality. Despite the solid evidence of these benefits, however, the exact mechanism by which this dietary combination can extend lifespan at the cellular level has remained unclear.
However, a recent study led by researchers at Stanford University has helped shed some light on this issue. By exploring how one of the healthy fats in the Mediterranean diet affects the longevity of nematodes (roundworms), Brunett and her team were able to examine the effects of the Mediterranean diet on cells and gain new insights into the health effects of different fats and the role diet plays in longevity.
The Mediterranean diet includes foods such as nuts, fish, and olive oil, which are rich in beneficial fats known as monounsaturated fatty acids (MUFAs). The study focused on oleic acid, one of the healthy fats found in olive oil and some nuts. The researchers discovered two benefits of oleic acid: it protects cell membranes from lipid oxidation damage and it increases the number of two major cellular components known as organelles.
These effects were found to make a significant difference, with roundworms fed oleic acid surviving about 35 percent longer than those on a more traditional diet. Additionally, exposure to elaidic acid – a monounsaturated trans fatty acid found in margarine and fried foods – had the opposite effect and increased oxidation at the expense of cellular integrity.
The study’s authors have noted the importance of these findings for our understanding of how long we can live and believe that they may eventually lead to improved dietary guidelines and strategies for addressing the effects of aging. They are also hopeful that similar associations between lipid droplets and longevity may be observed in mammals and humans. The study was published in Nature Cell Biology.