If you want to live longer and feel younger you should consider skipping a meal a day, a study suggests.
Researchers found restricting calories by a third in rats enhanced their immune systems, slashed inflammation and delayed the onset of age-related diseases.
While the benefits of eating less on lifespan have long been established, the study was the first to study the exact effect it has on a cellular level.
The international team of scientists, from the UK, US and China, now hope to apply their findings to humans.
If you want to live longer and feel younger you should consider skipping a meal a day, a study suggests (file)
Ageing is the highest risk factor for many human diseases, including cancer, dementia, diabetes and metabolic syndrome.
Caloric restriction has long been shown in animal models to be one of the most effective interventions against these age-related diseases.
And although researchers knew that individual cells undergo many changes as an organism ages, they have not known how caloric restriction might influence these changes.
Researchers – led by the Salk Institute for Biological Studies in California – isolated and analysed a total of 168,703 cells in 56 rats.
The animals’ diets were controlled from age 18 months through 27 months.
In humans, this would be roughly equivalent to someone following a calorie-restricted diet from age 50 through 70.
The cells came from fat tissues, liver, kidney, heart, skin, bone marrow, brain and muscle.
In each isolated cell, the researchers used single-cell genetic-sequencing technology to measure the activity levels of genes.
They also looked at the overall composition of cell types within any given tissue. Then, they compared old and young mice on each diet.
Overall, 57 per cent of the age-related deterioration in cells seen in the tissues of normal rats were not present in the calorie-restricted rats.
The number of immune cells in nearly every tissue studied dramatically increased as control rats aged but was not affected by age in rats with restricted calories.
In one type of fat tissue a calorie-restricted diet changed the way anti-inflammatory genes developed, reverting them back to resemble the genetic structure of younger rats.
Free radicals – unstable molecules that can damage cells – are released as a byproduct when the body digests food.
Calorie-restricted diets work because the cells are given time to wash away the free radicals, according to the researchers.
Juan Carlos Izpisua Belmonte, senior author of the new paper and a professor in the Gene Expression Laboratories at the Salk Institute, said the findings ‘gives us targets that we may eventually be able to act on with drugs to treat aging in humans.’
‘This approach not only told us the effect of calorie restriction on these cell types, but also provided the most complete and detailed study of what happens at a single-cell level during aging,’ said co-corresponding author Guang-Hui Liu, a professor at the Chinese Academy of Sciences.
‘The primary discovery in the current study is that the increase in the inflammatory response during aging could be systematically repressed by caloric restriction,’ said co-corresponding author Jing Qu, also a professor at the Chinese Academy of Sciences.
‘People say that “you are what you eat,” and we’re finding that to be true in lots of ways,’ says Concepcion Rodriguez Esteban, another of the paper’s authors.
‘The state of your cells as you age clearly depends on your interactions with your environment, which includes what and how much you eat.’
The new results were detailed in the journal Cell.
The team is now trying to utilize their findings in an effort to discover aging drug targets and implement strategies towards increasing life and health span.