Selenium, a powerful mineral that helps regulate metabolism and thyroid function, can also increase longevity. The researchers found that this vital nutrient could prevent obesity and enhance metabolic process in mice.
The study by Weill Cornell Medicine and the Orentreich Foundation for the Advancement of Science was published in Life on March 30, 2021.
Scientists say the findings may lead to treatments that emulate the anti-aging effects associated with dietary restriction. Best of all, people can continue to eat their usual diet while undergoing treatments.
The team said that some diets have been shown to extend lifespan while promoting health. Many organisms, including non-human mammals, have responded positively to restriction of methionine, an amino acid, in their diets. Recent studies have suggested that the same effects seen in other animals would likely apply to humans. A vegan diet automatically restricts methionine intake, but such a limited diet would not be practical for everyone.
In the current study, the OFAS research team in Cold Spring, New York, attempted to develop a different intervention. They wanted to reproduce the effects of methionine restriction while allowing people to eat a regular diet.
When developing this treatment, a key fact to remember is that methionine restriction lowers IGF-1, an energy-regulating hormone. If the intervention they developed could cause a similar decrease in IGF-1, it could also benefit lifespan. Previous studies have found that selenium supplementation reduces the amounts of circulating IGF-1 in rats, which looks promising for this research.
The study showed that selenium could increase longevity and protect against obesity.
First, the team wanted to investigate whether selenium supplementation could prevent obesity in the same way as methionine restriction. To do this, they gave young male and older female mice three different high-fat diets. The control group’s diet had moderate amounts of methionine, while the second group consumed a methionine-restricted diet. The last group followed a diet with moderate amounts of methionine along with selenium supplements.
The authors found surprising results in male and female mice of all ages in the control and methionine restriction groups. They found that selenium supplements offered total protection against obesity and fat accumulation in the mice.
They then studied how the three diets triggered physiological changes, which generally occur with methionine restriction. To achieve this, they measured the levels of four metabolic markers in blood samples from the mice. As they expected, the team observed dramatically reduced levels of IGF-1 in male and female mice alike. In addition, they found that the hormone leptin, which controls appetite and energy expenditure, had decreased.
Understanding the result
These results suggest that selenium supplementation reproduces most of the effects of methionine restriction. Furthermore, this implies that the treatment could have a positive impact on lifespan.
To better understand the benefits of selenium supplementation, the team tried the yeast experiment. They measured the two most common shelf life markers in yeast: chronological shelf life and replicative shelf life. The first shows how long dormant yeast remains viable. The latter reveals how many times a yeast cell can produce new offspring.
In previous studies, the team found that methionine restriction led to a longer chronological shelf life in yeast. In this study, they wanted to know if supplementation with selenium would have the same effect. The experiment revealed that the yeast given selenium supplementation had a 62% longer chronological lifespan (from 13 days to 21 days). Furthermore, their replicative life expectancy increased by nine generations compared to controls.
This shows that feeding yeast selenium supplements provides longevity benefits, seen in various tests of cellular aging.
“One of the main goals of aging research is to identify simple interventions that promote human health,” said lead author Jay Johnson, OFAS senior scientist. “Here we present evidence that short-term administration of organic or inorganic sources of selenium provides multiple health benefits for mice, the most notable being the prevention of diet-induced obesity. In the long term, we hope that supplementation with these compounds will also prevent age-related diseases and prolong the overall survival of the mice. We hope that many of the benefits seen for mice hold true for humans as well. “
Other benefits of selenium
In addition to improving life expectancy and preventing obesity, selenium offers many other benefits.
- It can reduce the risk of certain cancers. TO meta-analysis of 69 studies, involving more than 350,000 people, found that Taking selenium reduced the risk of certain cancers.. Cancers of the breast, lung, colon, and prostate appeared to respond positively to selenium.
- Protects against heart disease. A analysis of 25 observational studies revealed that the risk of heart disease decreased by almost 25% when selenium levels increased by 50%.
- Enrich cognitive health. One study found that Alzheimer’s patients had improved memory by consuming selenium in supplements or food.
Best sources from selenium:
- Oysters: 238% of the DV in 3 ounces (85 grams)
- Brazil nuts: 174% of the DV in a nut (5 grams)
- Halibut: 171% of the DV in 6 ounces (159 grams)
- Yellowfin tuna: 167% of the DV in 3 ounces (85 grams)
- Eggs: 56% of the DV in 2 large eggs (100 grams)
- Sardines: 46% of the DV in 4 sardines (48 grams)
- Sunflower seeds: 27% of the DV in 1 ounce (28 grams)
- Chicken breast: 12% of the DV in 4 slices (84 grams)
- Shiitake mushrooms: 10% of the DV in 1 cup (97 grams)
If you’re not getting enough selenium, you may want to add a little to your diet for a longer life. A single Brazil nut contains more than the RDI of selenium, for example, by providing an easy source for the mineral. Seafood, eggs, and certain types of meat are also high in selenium. In addition to prolonging lifespan, this essential mineral helps with thyroid function and may prevent obesity.
While we need very little selenium to survive, it could help us enjoy our time on Earth a little more.