Francisco de Vitoria University

Eating a vegan diet for eight weeks is associated with reductions in biological age estimates based on levels of DNA methylation, a type of chemical modification of DNA that alters the expression of genes, but not the DNA itself. This is the main conclusion of a study published in BMC Medicine in which 21 pairs of twins participated in a clinical trial. Of each pair, one person followed an omnivorous diet and the other a vegan - and lower calorie - diet during that period.

Research published in JAMA Network Open suggests that exposure to common environmental toxicants is associated with depressive symptoms. The authors analysed data from urine or blood samples from more than 3,400 US adults and found that 27 environmental toxicants were associated with these symptoms, which could be linked to inflammatory processes.

People who eat more ultra-processed foods have a "slightly higher" mortality rate, according to an analysis published in The BMJ. The study analysed data from more than 110,000 people followed up for over 30 years in the United States. The correlation between ultra-processed food intake and all-cause mortality was strongest for the meat, poultry and seafood group. 

Eating more ultra-processed foods is linked to a higher risk of health problems, according to an umbrella review of 45 previous meta-analyses, involving almost 10 million people in total. The research, published in The BMJ, finds direct associations between exposure to ultra-processed foods and 32 health parameters. The strongest evidence links this exposure to cardiometabolic health problems, mental disorders and overall mortality.

Research involving 10,775 adults shows that a higher percentage of daily energy intake from ultra-processed foods was associated with cognitive impairment. The results are published in the journal JAMA Neurology.