By Faculty of Medicine
The timing of adopting healthy eating habits could be as crucial as the type of food consumed in determining lifespan, according to a new study by Universiti Kebangsaan Malaysia (UKM).
Published in Experimental Gerontology, the study shows that beginning a mild dietary restriction (DR) shortly after the body completes its growth phase can significantly prolong life.
The research, led by Associate Professor Dr. Goon Jo Aan from the Department of Biochemistry, Faculty of Medicine, UKM, involved the use of Caenorhabditis elegans, a microscopic worm commonly used in aging studies.
The findings revealed that worms placed on a calorie-restricted diet in early adulthood lived 35 percent longer compared to those that ate freely.
“Young worms placed on a calorie-restricted diet lived far longer than their counterparts.
“Older worms, however, didn’t benefit from the regime, proving that timing matters. This finding shines a spotlight on the body’s ‘cellular clock’, which seems more responsive and adaptable at a younger age,” she said.
She added that many individuals tend to adopt healthy eating habits only later in life.
However, the study suggests that the body is more receptive to dietary changes at an earlier stage, possibly even before any visible signs of aging appear.
“Waiting too long to start restricting your diet may mean missing the window of maximum benefit.
“A few mindful changes to your eating habits especially earlier in life could be a game changer for your long-term health and vitality.
“Whether you’re in your 20s or encouraging your teens to eat better, this is a wake-up call from science. Begin healthy habits soon after reaching full physical maturity, eat smart, and extend your healthspan,” she said.
She added that the study identified several key biological pathways that mediate the lifespan-extending effects of dietary restriction.
“A central mechanism is the downregulation of the mTOR pathway, which shifts the body from growth mode to repair mode by reducing protein synthesis and activating autophagy, the process by which cells clear out damaged components.
“In addition, DR also promotes the use of fats over glucose as an energy source.
“Metabolomic data revealed significant reductions in amino acids such as leucine, tyrosine, and methionine, which further suppress mTOR signalling and promote autophagy.
“The decline of regulators of methylation and inflammation suggests DR promotes a metabolic shift toward enhanced cellular maintenance, detoxification, and stress resistance, all of which contribute to improved healthspan and extended lifespan,” she said.
Dr Goon added that although the study was conducted in worms, the underlying biological mechanisms, especially nutrient-sensing pathways like mTOR, and insulin signalling, are conserved in humans.
“This means the findings could also apply to humans.
“In fact, diets that moderately reduce calories, or those that limit protein or specific amino acids (like methionine and leucine), are already being explored for their anti-ageing effects in people,” she said.
The study, titled “Elucidating the Effective Age for Dietary Restriction and the Key Metabolites Involved,” was published in Experimental Gerontology in June 2024.
Associate Professor Dr. Goon Jo Aan
Department of Biochemistry
Faculty of Medicine, UKM