According to the research team, this mild biological stress encourages cells to activate their protective mechanisms.
The study, published in the journal Nature Communications, used Caenorhabditis elegans, a species of microscopic worm. Scientists found that certain RNA molecules present in the worms' diet helped them maintain vitality as they aged.
Professor Anne Spang stated, "These molecules prevent the formation of harmful protein aggregates, which are associated with aging and diseases." As the body ages, it becomes less efficient at clearing damaged proteins. The accumulation of these proteins in cells can contribute to the development of neurodegenerative diseases like Alzheimer's and Parkinson's.
The researchers determined that a balanced diet slows these processes and that some nutrient components provide a protective effect on cells. The double-stranded RNA molecules found in the bacteria the worms consumed are absorbed in the digestive system, triggering intracellular quality control mechanisms.
"This low-level stress makes the body more resilient to protein damage," said the study's first author, Emmanouil Kyriakakis.
This diet-induced signaling activates the cells' self-cleaning process known as "autophagy." This mechanism breaks down and reuses damaged proteins, thereby slowing cellular aging.
Kyriakakis added, "The gut communicates not only locally but with the entire body. The protective effect was observed not just in the digestive system, but also in the muscles and other organs."
Worms fed a balanced diet were found to be more mobile and healthier as they aged. The RNA molecules consumed through the diet were observed to generate a systematic stress response throughout the entire organism, protecting it from age-related protein accumulation.
Spang concluded, "Some food components can stimulate the body's own protective mechanisms. In other words, a small amount of stress can actually be beneficial."
The researchers stress that it is not yet clear whether this effect will yield similar results in humans. However, one fact is already apparent: what we eat shapes how we age.
