Accelerated Aging
Researchers at the Georgia Health Sciences University recruited 766 adolescents aged 14 to 18 and grouped them according to their sodium intake.
The researchers found that obese adolescents with high salt intake had significantly shorter telomeres—the protective caps on chromosomes—compared to their obese peers with normal salt intake. However, for adolescents of normal weight, sodium intake did not have a significant impact on telomere length.
Human cells contain structures on chromosomes called telomeres, which act like the protective tips on shoelaces to prevent fraying. At birth, telomeres are of a certain length. As cells divide and age, telomeres gradually shorten, leading to DNA damage and increasing susceptibility to age-related diseases such as Alzheimer's, diabetes, and heart disease.
Telomere length is considered an important marker for biological aging. Shorter-than-average telomeres are a sign of poor health and are associated with a higher risk of premature death.
Synergistic Effect
The researchers presented these findings at the American Heart Association's 2014 Epidemiology and Prevention/Nutrition, Physical Activity and Metabolism Scientific Sessions.
The British newspaper The Daily Mail reported on the 24th, citing the researchers: "Even in relatively healthy young populations, we can already see the effects of high sodium intake, suggesting that high sodium intake and obesity may act synergistically to accelerate cellular aging."
The researchers explained that obesity is associated with chronic inflammation, which also accelerates telomere shortening and makes telomeres more sensitive to sodium. This may help explain why high salt intake has a more significant impact on overweight individuals.
Recommendation to Reduce Salt
Previous studies have shown that excessive salt intake can lead to high blood pressure. Many experts warn that excessive salt consumption may increase the risk of heart disease and stroke. The World Health Organization recommends that the daily salt intake for a normal person should not exceed 5 grams, while the American Heart Association lowered this recommended limit to 1.5 grams in 2011. In reality, most people's daily salt intake currently exceeds 10 grams.
Researchers at the Georgia Health Sciences University stated: "For overweight young people looking to reduce their risk of heart disease, reducing sodium intake may be much easier than losing weight, and it can be a first step in that direction."
They also suggest that since a large amount of sodium in the diet comes from processed foods, parents can cook more fresh meals for their children and encourage the consumption of fresh fruit as a substitute for snacks.
