The Mediterranean diet, which features plenty of vegetables, fruits, herbs, nuts, beans and whole grains, has long been lauded for its heart health benefits. But now a new study shows that it could also improve brain function in elderly people, even when only eaten for a year. According to the research published in the BMJ, following a Mediterranean diet for just 12 months can inhibit production of inflammatory chemicals in elderly individuals that can lead to loss of cognitive function, as well as prevent the development of chronic diseases such as diabetes, cancer and atherosclerosis. For the study, 612 elderly people from France, Italy, the Netherlands, Poland and the United Kingdom has their gut microbiome analysed. Then, 323 of them were put on a special diet, based on Mediterranean principles, for one year, while the rest were asked to eat as they normally would. After 12 months, all of the study participants had their gut microbiome re-analysed. Those who had followed the Mediterranean diet saw beneficial changes to the microbiome in their digestive system. The rate at which bacterial diversity was lost slowed and the production of potentially harmful inflammatory markers was reduced. Furthermore, there was also a growth of beneficial bacteria linked to improved memory and brain function. So-called “keystone” species, critical for a stable “gut ecosystem”, were also boosted, helping to slow signs of frailty, such as walking speed and hand grip strength. “Our findings support the feasibility of changing the habitual diet to modulate the gut microbiota which in turn has the potential to promote healthier aging,” the study authors said.
The modern, germ-free lifestyles many children lead could be responsible for the most common type of cancer in children - acute lymphoblastic leukaemia - according to one of the UK’s most well-respected scientists. Professor Mel Greaves, from the Institute of Cancer Research, has been studying for 30 years how the immune system can become cancerous if it is not exposed to enough bugs early in life. Acute lymphoblastic leukaemia affects one in 2,000 children and is more common in advanced, affluent societies, suggesting cleaner modern lifestyles could play a defining role. Prof Greaves says the disease happens in three stages: a genetic mutation inside the womb, a lack of exposure to microbes in early life and an immune malfunction and leukaemia in childhood. He believes that it could be possible to prevent the condition. Prof Greaves said: "The research strongly suggests that acute lymphoblastic leukaemia has a clear biological cause and is triggered by a variety of infections in predisposed children whose immune systems have not been properly primed." Unfortunately, preventing the disease isn’t as simple as exposing children to dirt. They need, according to Prof Greaves, contact with beneficial bacteria. The best way to do this is to give them a safe cocktail of bacteria, such as in a yoghurt drink, that will help boost their immune system. [Related reading: Thumb-suckers and nail-biters less prone to allergies – study]