Association of Dietary Magnesium Intake With Leukocyte Telomere Length in United States Middle-Aged and Elderly Adults

      
    

        

         

Telomeres, the TTAGGG repetitive DNA at the ends of linear chromosomes, are important and active controllers of cellular lifespan and chromosome integrity in eukaryotes cells. Telomere attrition is an integral part of the end replication problem; thus, leukocyte telomere length (LTL) shortening has been viewed as a useful bioindicator for cellular aging. In addition, acceleration of the rate of telomeric sequence loss is a feature of a plethora of adverse health outcomes. 

   

    

Shortened LTL has been reported to be linked with increased risk for numerous chronic conditions, including cardiovascular disease, diabetes mellitus, Alzheimer’s disease, hypertension, and cancer. Growing evidence suggests that LTL can be influenced by lifestyle factors, such as smoking, physical activity, and energy intake. Recently, the importance of nutritional factors on LTL has been increasingly recognized.

   

    

Magnesium is an essential element, as a cofactor, by over 300 enzymatic reactions required to maintain homeostasis.

Diet is the major source of magnesium in humans.
Nuts, seeds, leafy vegetables, or whole-grain cereals are well-recognized dietary sources of magnesium.

Unbalanced magnesium intake can cause adverse health effects. 

    
      

Observational studies have shown that magnesium deficiency is associated with poor cardio-metabolic conditions. An increasing body of epidemiologic evidence reported that higher dietary magnesium intake could exert beneficial effects on CVD risk factors by improving glucose and insulin metabolism, ameliorating lipid profile, and by its actions as an antihypertensive and anti-inflammatory agent. 

    

   
    

    

      

   

However, whether LTL plays a role in prolonging lifespan with magnesium intake remains unclear. Although some studies have explored the associations between mineral intake (e.g., copper, zinc, and selenium) and LTL, the association of dietary magnesium intake with LTL has rarely been examined. Of note, the possible effect modifiers for the dietary magnesium intake-LTL association have not been fully investigated in previous studies. Therefore, the present study aimed to address the knowledge gap by examining the association of dietary magnesium intake with LTL and to explore any possible effect modifiers in United States middle-aged and elderly adults using a large population-based survey data, the National Health and Nutrition Examination Survey (NHANES).

     
              
              

                

                 

Summary of the Study

    

      

Aim: 

Magnesium supplementation may extend the life span; however, the biological mechanism is still unknown. Leukocyte telomere length (LTL) is a marker of cell aging and biological health in humans. Data concerning whether magnesium supplementation can maintain telomere length, thus prolonging life are limited. We aimed to investigate the association between dietary magnesium intake and LTL in the United States middle-aged and elderly adults.

Methods: 

A total of 4,039 United States adults aged ≥ 45 years from the National Health and Nutrition Examination Survey (1999–2002). Dietary magnesium intake was collected by a trained interviewer using 24-h dietary recall method and LTL was obtained using the quantitative polymerase chain reaction method. Multiple linear regression analysis was performed to evaluate the crude and adjusted association of dietary magnesium intake with LTL.

Results: 

The overall mean (SD) of LTL was 5.6 (0.6) kp. After adjusting potential confounders, every 1 mg increase in log-transformed dietary magnesium intake was associated with 0.20 kp (95% confidence intervals: 0.05–0.34) longer LTL. Participants with the highest tertile (≥299 mg) of dietary magnesium intake had statistically significant longer LTL (β = 0.07, P = 0.038) compared with the lowest tertile (<198 mg), with significant linear trends across tertiles. Moreover, the association between dietary magnesium intake and LTL was significantly stronger in participants with higher levels of education (≥high school compared with < high school, P for interaction = 0.002). E-value analysis suggested robustness to unmeasured confounding.

Conclusion: 

Our findings showed that increased dietary magnesium intake was associated with longer LTL, which suggested that magnesium was conducive to a longer life expectancy.

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Story Source:

Association of Dietary Magnesium Intake With Leukocyte Telomere Length in United States Middle-Aged and Elderly Adults. Hu L, Bai Y, Hu G, Zhang Y, Han X and Li J (2022) https://doi.org/10.3389/fnut.2022.84080 Frontiers in Nutrition. 9:840804. Published: 19 May 2022