Researchers at Universidade Harvard released results of a randomized clinical trial that demonstrates the role of vitamin D supplementation in preserving telomeres. The work is part of the VITAL project and followed participants for four years with regular measurements of these structures in DNA. The analysis indicated less loss of base pairs in telomeres among those who received the supplement.
The study involved 1,054 adults aged 50 and over. Measurements took place at the beginning, after two years and at the end of four years. Data were collected at clinical centers in the Estados Unidos.
- The supplementation used 2000 IU of vitamin D3 per day.
- The treated group preserved an additional 140 base pairs.
- This result is equivalent to approximately three years less biological aging.
How vitamin D works against cell aging
Vitamin D exerts an anti-inflammatory action that protects genetic material from accumulated oxidative damage. Essa protection stimulates enzymes responsible for maintaining chromosomal ends. Cells are thus able to carry out more divisions without losing essential functionality.
Telomeres function as protective caps at the ends of chromosomes and shorten with each cell replication. Quando reach critical length, cells enter senescence or programmed death. Supplementation helps to slow down this natural shortening.
Research has identified that adequate levels correlate with greater telomerase activity in leukocytes. Esse effect was observed consistently throughout the four years of intervention.
More on this story: New clinical analysis confirms the effectiveness of vitamin D in protecting DNA and reducing biological age
Where to find vitamin D in everyday life
Sun exposure for 15 to 20 minutes daily on the arms and legs activates natural synthesis in the skin. Essa free font depends on latitude, season and skin type. Pessoas with darker phototypes need slightly longer time to obtain the same amount.
Fatty fish like salmon, sardines and tuna provide significant amounts in each serving. Egg yolk represents an affordable and versatile option for inclusion in meals. Cogumelos exposed to the sun increases the content and serves as a vegetable alternative.
Fortified milks and cereals complement the daily intake, especially in regions with low sunlight. A combination of dietary sources and moderate exposure is usually sufficient for most healthy people.
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Supplementation becomes recommended when diet and sunlight do not meet individual needs.
Clinical trial of Harvard proves the protective effect of vitamin D on telomeres
The VITAL Telomere trial included 1054 participants evaluated in person at the Harvard clinical site. The measurement of telomere length in leukocytes used a quantitative PCR technique. The samples totaled 2571 analyzes carried out at three different moments of the study. The work was double-blind and placebo-controlled to eliminate bias of any nature. The cohort included men aged 50 and over and women aged 55 and over, reflecting representative ethnic diversity.
Vitamin D3 supplementation reduced loss by 0.14 kilobases over four years compared to placebo. Trend analysis showed an average annual gain of 0.035 kilobases in the treated group. The p-value of 0.039 confirmed statistical significance of the main result. The main VITAL project simultaneously tested vitamin D and omega-3 in more than 25 thousand volunteers. Nenhum relevant effect was detected with omega-3 supplementation alone.
Other health benefits of vitamin D
Vitamin D facilitates the absorption of calcium and phosphorus essential for maintaining bone density. Esse mechanism helps prevent osteoporosis and reduces the risk of fractures in elderly populations. Estudos observational studies associate adequate levels with a lower incidence of falls related to muscle weakness.
Learn more: Harvard research shows that vitamin D supplementation slows the aging of human DNA
The immune system receives direct support that modulates inflammatory responses and strengthens barriers against pathogens. The reduction in the risk of respiratory infections appears in analyzes of cohorts with corrected deficiency. Cardiovascular function benefits from adequate levels that contribute to blood pressure control.
Factors that influence vitamin D levels in the body
People who spend long hours indoors are more likely to develop deficiency even in sunny regions because skin synthesis directly depends on exposure to UVB radiation. Idosos produce less vitamin D in the skin due to natural physiological changes that reduce the conversion capacity. Indivíduos with darker skin need prolonged sun exposure to synthesize the same amount as people with light skin. Regiões geographical areas with long winters and little UVB radiation record high rates of insufficiency during entire months of the year. Constant use of sunscreen partially blocks skin production, although it protects against other important dermatological risks. Obesity can sequester vitamin D in adipose tissue and significantly reduce its circulating bioavailability. Trabalhadores night shifts or reverse shifts face chronic imbalance in skin synthesis. Exames blood samples for measuring 25-hydroxyvitamin D are simple and widely available in clinical laboratories.
Practical recommendations for maintaining adequate vitamin D levels
The recommended daily intake varies depending on the age and specific clinical conditions of each individual. Adultos healthy people generally aim for between 600 and 2000 IU depending on their usual sun exposure. Supplementation in drops or capsules makes it easier to precisely adjust the dose.
Technical details of the VITAL telomere study
The main project simultaneously tested vitamin D and omega-3 fatty acids in more than 25,000 volunteers. Telomere subanalysis focused on participants close to the center of Boston to allow for in-person collections.
The researchers applied mixed linear regression models to compare variations in telomere length. Measurements occurred at baseline, year two and year four with no relevant effects of omega-3 alone.