Strategies to Slow Telomere Shortening

 

Telomeres, the structures at the end of chromosomes, help to protect DNA from damage and allow chromosomes to replicate properly during cell division. Aging is a complex, multifactorial process that starts in our cells, resulting in a gradual decline of the larger systems in the body. Scientists have proposed various theories for the reason we age, including oxidative stress, mitochondrial dysfunction, cell senescence, and telomere shortening.

Telomere shortening is one key biological process linked to aging, acting as a "mitotic clock" that limits the number of times a cell can divide. Each time a cell divides, telomeres — protective caps made of repetitive DNA sequences (TTAGGG in humans) — shorten by about 24 to 40 base pairs per year, depending on the study. When telomeres become critically short, cells enter senescence (irreversible growth arrest), undergo apoptosis (programmed cell death), or become dysfunctional, contributing to tissue degeneration and age-related diseases.

This shortening is a natural consequence of DNA replication, as the enzyme DNA polymerase cannot fully replicate the ends of linear chromosomes. While telomerase — a reverse transcriptase enzyme — can counteract shortening by adding DNA repeats, it is only active in germ cells, stem cells, and certain immune cells. In most somatic cells, telomerase activity is low or absent, leading to progressive telomere attrition over time.

Shorter telomeres are strongly associated with:

Increased risk of cardiovascular disease, diabetes, Alzheimer’s, and cancer

Higher mortality from heart disease and infectious diseases

Biological aging, which can exceed chronological age

Lifestyle factors such as chronic stress, smoking, obesity, poor diet, pollution, and lack of exercise accelerate telomere shortening by increasing oxidative stress and inflammation. Conversely, healthy behaviors — like a Mediterranean diet, regular physical activity, stress reduction, and adequate sleep — may help preserve telomere length and slow aging.

Some research suggests that telomere length below 5 kilobases may represent a "telomeric brink," associated with a significantly increased risk of death, potentially setting a biological limit to human lifespan. Thus, telomere length serves as a promising biomarker of biological age and a key focus in aging and longevity research.

So, how does one increase telomere length?

Lengthening telomeres is a complex process, but there are several science-backed strategies that can help promote telomere health and potentially slow down the shortening of telomeres.

1. Focus on a plant-rich diet for longer telomeres

Individuals with healthier diets tend to have longer telomeres, a lower risk of chronic diseases, and a longer lifespan.

A recent 2019 meta-analysis analyzed over 20 studies — both observational and interventional — to examine the association between diet and telomere length (TL). The researchers found that adherence to a Mediterranean diet, or a plant-rich diet, was linked to longer telomeres.

When looking at isolated foods, unrefined grains, nuts and seeds, and coffee were all associated with longer telomeres. The researchers also found that a diet rich in carotenoids, a nutrient found in leafy greens and red-orange colored fruits and vegetables, was significantly associated with longer telomeres.

Mediterranean and plant-rich diets consist of nutrient-dense, high-fiber foods, and healthy antioxidant-rich fats like omega-3 fatty acids. The components of these diets help to reduce inflammation and oxidative stress in the body — two mechanisms that may otherwise accelerate telomere shortening.

Individual studies further validate the relationship between nutrients of a plant-rich diet and TL. One large cross-sectional study found that those who consumed more fiber also had longer telomeres, while another study showed a diet rich in omega-3s was associated with a slower rate of telomere shortening.

Lastly, in this study, women who consumed a diet rich in antioxidants, particularly vitamins E & C and beta-carotene, had longer telomeres and a lower risk of developing breast cancer. The opposite was also true—a low intake of these nutrients was associated with shorter telomeres and a moderate risk of developing breast cancer.

2. Protect telomeres by engaging in physical activity

Both physical activity and exercise help preserve telomere length. One large-scale investigation from the National Health and Nutrition Examination Survey examined over 5,000 people and concluded that individuals who exercise more tend to have longer telomeres than those who lead more sedentary lives.

Similar to a nutrient-dense diet, engaging in physical activity helps to decrease oxidative stress and inflammation in the body, helping to protect telomeres from damage.

Furthermore, telomerase — the enzyme that helps maintain telomere length — activity may also increase in more active people. Werner et al. examined telomere activity among athletes and found that athletes had increased telomerase activity and reduced telomere shortening compared to non-athletes.

3. Choose folate, not folic acid, for optimal telomere length

Folate, an essential B vitamin found in food, may play a role in protecting and increasing telomere length. Some studies demonstrate that individuals with adequate folate levels have longer telomeres, while a deficiency in the vitamin can lead to DNA damage and shorter telomeres.

But, too much folate isn’t necessarily a good thing either. Scientists discovered in a 2009 study that individuals with the highest folate levels had shorter telomeres.

Folate is often added to our food supply (bread, cereal, and pasta) and to multivitamins in its synthetic form, folic acid. Folic acid acts differently in the body compared to natural folate, as its bioavailability is significantly higher (85% compared to 50%). To ensure proper amounts of folate, focus on natural sources of the vitamin, including:

• Spinach

• Asparagus

• Artichoke

• Broccoli

• Most legumes

4. Supplement with vitamin D to improve already short telomeres

A strong relationship also exists between vitamin D and telomere length. A study published in The Journal of Frailty & Aging found that higher vitamin D levels were associated with longer telomere length.

Vitamin D has many functions in the body, including its role in modulating inflammation—a mechanism that may protect telomeres as well. What’s more, supplementing with vitamin D may also help lengthen already shortened telomeres.

In a randomized control trial, older adults with mild cognitive impairment (MCI) were administered 800 IU of daily vitamin D. After 12 months of supplementation, the experimental group had significantly improved measures of oxidative stress and MCI, and longer telomeres relative to the control group. This study suggests that vitamin D can help reduce oxidative stress, leading to longer, healthier telomeres.

5. Extend your life and telomeres by keeping stress at bay

Chronic levels of stress drive up cortisol levels and increase oxidative stress, both factors in telomere shortening.

In one fascinating study, two groups of women had their perceived stress levels and telomere length measured. The control group consisted of mothers of healthy children, while the experimental group was comprised of mothers of chronically ill children (“caregivers”). The caregivers had significantly reduced telomerase activity and shorter telomeres compared to the women in the control group.

The authors of the study also noted that the difference in telomere length between the two groups was “equivalent to 10 years of life,” meaning the women under more stress faced a greater risk of age-related health issues.

by Diana Licaizi at insidetracker.com on March 4, 2024