Someone has rightly said, 'healthy eating begins with you.' Nourishing your body with the right nutrients and maintaining a healthy weight can help you stay active and independent even as you age. According to a recent study published in the journal Nature Metabolism, reduced intake of food in both humans and animals may improve health in their old age, further leading to longevity. However, in order to improve health in old age and to extend lifespan, the pattern of the diet (diet plan) must be established earlier in life. Scientists from the Max Planck Institute for Biology of Ageing, the Excellence Cluster for Ageing Research at the University of Cologne, the Babraham Institute in Cambridge and UCL observed that mice become healthier when they were fed in moderation from early stage and maintained it before entering old age.
However, the question remains, how can we stay fit and healthy in old age for as long as possible? To investigate the same, in an animal-based study, a team of researchers led by Linda Partridge (Director at the Max Planck Institute for Biology of Ageing) put young and old mice on a diet - with varying degrees of success. To prevent malnutrition, the dieting mice were fed food, which was enriched with vitamins and minerals. As per the findings of the study, mice live healthier and longer if they are given 40 per cent less to eat after reaching adulthood than animals who are allowed to eat as much as they want. To have positive effects on health in old age, reduced food intake must be implemented early and be sustained until the end of their lives.
"One should establish healthy behaviours early in life. It may not be as good for your health to change your diet later in life. Health in old age is a lifelong affair", explains Linda Partridge from the Max Planck Institute for the Biology of Ageing and UCL.
Oliver Hahn, the first author of the study and doctoral student in the Partridge department investigated gene activity in different organs to assess why older mice no longer react to the change in diet.
While the gene activity in the liver quickly adapted when mice are transferred to a restricted diet, a 'memory effect' was observed in the fat tissue of older animals. This memory effect mainly affects mitochondria, which play an important role in the ageing process.
While a reduced food intake leads to increased formation of mitochondria in fatty tissue, the findings of the study showed that this is no longer the case when older mice are switched to a lower calorie diet. At the genetic and metabolic levels, this inability may contribute to the shortened lifespan of these animals.
Michael Wakelam, co-corresponding author and Director of the Babraham Institute commented, "The experimental power of integrating data about lipid metabolism and metabolic pathways with the tissue-specific understanding of gene expression in mice of different ages and diets has allowed us to demonstrate clearly the importance of a nutritional memory in contributing to healthy ageing."