Scientists have been searching for ways to slow the aging process for many years.
A large new study now suggests that vitamin D supplements may help protect the body at the cellular level, possibly slowing one of the natural changes that happens as we grow older.
The research was published in The American Journal of Clinical Nutrition.
The study comes from the VITAL trial, a large clinical study carried out in the United States. More than 25,000 adults took part in the trial, making it one of the biggest studies to examine the health effects of vitamin D.
Researchers closely examined a smaller group of 1,054 participants to measure changes in their cells over time.
The scientists focused on structures called telomeres. Telomeres are protective caps found at the ends of chromosomes, which contain our genetic information. They work much like the plastic tips on shoelaces, helping protect our DNA each time a cell divides.
As people get older, telomeres naturally become shorter. When they become too short, cells no longer work as well as they should.
Shorter telomeres have been linked to aging and a higher risk of diseases such as heart disease, some cancers, and autoimmune disorders.
The participants included women aged 55 years and older and men aged 50 years and older. Blood samples were collected at the beginning of the study and again after two years and four years. Some people took 2,000 international units (IU) of vitamin D3 every day, while others received a placebo with no active ingredient.
The researchers found that people taking vitamin D had less telomere shortening than those taking the placebo. The difference was equal to slowing about three years of biological aging during the four-year study period. This suggests vitamin D may help protect cells as people age.
The study also tested omega-3 fatty acid supplements. Unlike vitamin D, omega-3 supplements did not show a clear effect on telomere length.
Dr. JoAnn Manson, one of the study leaders from Brigham and Women’s Hospital, said this is the first large, long-term clinical trial to show that vitamin D may help preserve telomeres. Researcher Dr. Haidong Zhu said the findings suggest vitamin D could slow aging at the level of individual cells.
Earlier findings from the VITAL study have suggested that vitamin D may also reduce inflammation and lower the risk of certain cancers and autoimmune diseases. This new research adds another possible benefit, although scientists say more studies are needed to understand exactly how vitamin D protects telomeres and whether this leads to a longer, healthier life.
Vitamin D is already well known for helping keep bones strong and supporting the immune system. It can be obtained through sunlight, some foods, and supplements. Although vitamin D supplements are generally safe when taken at recommended amounts, people should speak with their healthcare provider before starting them because the right dose can vary from person to person.
Overall, this study suggests that vitamin D may have a larger role in healthy aging than previously thought. Protecting telomeres could help slow one of the basic processes linked to aging, making vitamin D an exciting area for future research.
If you care about health, please read studies that vitamin D can help reduce inflammation, and vitamin K could lower your heart disease risk by a third.
For more health information, please see recent studies about new way to halt excessive inflammation, and results showing foods that could cause inflammation.
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