There are many important supplements that can help people with specific deficiencies and certain health conditions. However, research has shown experts that some synthetic vitamins may do more harm than good.
“Everyone is always looking for the magic pill that will give them great health, but that’s not the case with dietary supplements, because the benefits often don’t outweigh the risks,” says Dr. says Joan Manson, director of preventive medicine. Boston, Massachusetts.
This is not to say that some groups of people don’t need to supplement with certain nutrients at some point in their lives. However, most people don’t need to supplement with all the vitamins they think they need.
“In general, we do not recommend the use of vitamin supplements unless there is a specific reason,” says Walter Willett, professor of epidemiology and nutrition at Harvard’s T.H. Chan School of Public Health.
Such advice applies especially to fat-soluble vitamins.
water soluble and fat soluble
Water-soluble and fat-soluble nutrients are absorbed differently in the body.
Water-soluble vitamins, including vitamin C and all eight B vitamins, are quickly dissolved, processed, and metabolized by the body. do not have kept for later use.
“Excess amounts of water-soluble vitamins are excreted in the urine,” explains Alice Lichtenstein, director of the cardiovascular nutrition team at the Jean Mayer USDA Center for Aging and Human Nutrition Research at Tufts University.
On the other hand, vitamins A, D, E, and K, which are fat-soluble nutrients, are stored in the liver and adipose (adipose) tissue throughout the body for future use. This will help you store up vitamin D to compensate for the summer sun. Less exposure to sunlight The winter months also mean that these vitamins can accumulate to potentially toxic levels.
This is why the Tolerable Upper Intake Level (UL) safety guidelines have been established. provided by The National Academies of Sciences, Engineering, and Medicine indicate the maximum amounts of certain vitamins that can be safely taken without adverse health effects.
“Fat-soluble vitamins tend to have lower UL values than water-soluble vitamins, highlighting the need for caution when consuming them,” says Jenn, R.D., president-elect of the New Hampshire Academy of Nutrition and Dietetics. Messer explains.
Of the four fat-soluble vitamins, experts say vitamin A and vitamin E require more attention than the others.
Concerns about vitamin A
Vitamin A is important for vision, growth, reproduction, and immune health.When ingested through natural food sources Beef liver, sweet potatoes, spinach, carrots, pumpkin pie, etc. Recommendation Vitamin A intake of 900 micrograms per day for adult men and 700 micrograms per day for adult women is considered safe and essential.
The upper limit of daily intake of vitamin A is 3,000 microgramsHowever, it is important to note that such allowances include the consumption or absorption of things such as: all Sources of vitamin A such as foods, supplements, and creams/lotions containing retinol. (For context, consider that one 3-ounce serving of pan-seared beef liver contains 6,582 micrograms of the vitamin.)
Exceeding the UL is dangerous, and “taking large amounts at once can contribute to toxicity,” explains Yufan Lin, a primary care physician at the Cleveland Clinic Center for Integrative Medicine. Such toxicity can cause problems such as joint pain, liver damage, and birth defects.
“Vitamin A is essential for normal fetal development, but in excess it can harm both the mother and the developing fetus, increasing the risk of birth defects in the eyes, heart, organs, and central nervous system. “Yes,” says Dr. Messer. .
Among them modest amount Even outside of pregnancy, “vitamin A supplements have the following effects.” skin irritation and increased Fracture risk” says Manson.
Published research Research earlier this year showed that vitamin A toxicity can also be caused by topical vitamin A (retinol), which is used to treat acne and psoriasis.
There was also a problem with the presence of vitamin A in multivitamins. “At one point, there was concern about the amount of vitamin A in multivitamin supplements and bone loss in older women,” Lichtenstein explains. She says this is why some multivitamin brands now include only vitamin A in the form of beta-carotene as an ingredient. (According to research Beta-carotene is converted to vitamin A in the body, but there are few risks associated with other forms. )
In addition, some According to research Vitamin A from a balanced diet may reduce the risk of certain cancers. NIH Office of Dietary Supplements Note The form of the supplement increase Vitamin A’s role in regulating cell growth and differentiation increases the risk of certain cancers.
“Long-term high-dose vitamin A intake can also lead to liver disease, elevated blood lipids, bone and muscle pain, and vision problems,” says Kate, R.D., a registered dietitian at the Mayo Clinic in Rochester, Minnesota. Zeratsky says. “Early signs of vitamin A toxicity may include dry skin, nausea, headaches, fatigue, enlarged liver, and hair loss.”
Concerns about vitamin E
Vitamin E is a more controversial fat-soluble supplement.
Found naturally in foods such as wheat germ oil, avocado, fish, seeds, and nuts such as almonds, hazelnuts, and peanuts, vitamin E is a powerful compound that protects cells from the effects of free radicals and improves skin and eye health. It is an antioxidant.
However, the Department of Nutrition at Harvard T.H. Chan School of Public Health Note The safety profile of its synthetic forms is a matter of debate among scholars. “Because adverse health effects of vitamin E supplements have been reported from time to time, scientists are debating whether these supplements can be harmful or even promote health. ” risk of death. ”
One of the points of controversy and confusion regarding vitamin E is the fact that this nutrient comes in multiple forms, some of which are better studied than others.
“Vitamin E exists in eight chemical forms in nature, but most vitamin E supplements are synthetic alpha-tocopherol,” Lin explains. This form of alpha-tocopherol appears to pose a higher risk than other forms of vitamin E. “This is an argument that it is better to eat foods rich in vitamin E than to take synthetic supplements.”
Zeratsky agrees. “I think we need a deeper understanding of how different forms of vitamin E act and interact in our bodies,” she says.
There is also confusion about the amount of vitamin E that can be safely taken.Every day of Recommended dietary allowance The RDA for vitamin E is 15 milligrams for both adult men and women, but the upper limit for daily intake is 1,000 milligrams. NIH Office of Dietary Supplements Note “Taking vitamin E supplements even below these limits can cause harm.”
surely, clinical research Studies show that consuming just 268 milligrams of vitamin E each day can increase a man’s risk of prostate cancer by 17 percent. The shapes used in supplements are A link with lung cancer has also been pointed out..
“And you don’t have to reach toxic levels to experience the downside,” Manson added. “Randomized trials of vitamin E have documented problems even at moderate doses.”
High doses of vitamin E supplements can also interfere with blood clotting. may cause bleedingsays Jessica Rose, an obesity dietitian at the University of Maryland Upper Chesapeake Health.
Because of these and other issues, Published research According to the American Heart Association, high levels of vitamin E supplementation, which is necessary to protect against chronic diseases such as cancer, arthritis, and cataracts, are no longer recommended.
“Ultimately, it is important to assess the balance between potential risks and benefits,” Messer explains.
Lack of regulation for dietary supplements
Another concern for experts that affects both water-soluble and fat-soluble vitamins is that supplement nutrients are not regulated by the U.S. Food and Drug Administration (FDA) using the same standards as foods and drugs. is.
This can lead to unsubstantiated claims and labels that misrepresent the ingredients inside each supplement bottle. “According to some, Recent independent analysis “Of the 57 dietary supplements, 84 percent did not contain the listed amount of the ingredient, and 40 percent of the supplements did not contain any of the listed ingredient.” Messer said. “Additionally, 12 percent of the supplements contained undeclared ingredients, which are prohibited by the FDA.”
Therefore, consumers should choose trusted supplement brands and purchase products that have been tested and marked by established third-party organizations. “And be very wary of supplements that claim they can treat diseases, because supplements are not allowed to make such claims,” says Lin.
It’s also important to check the recommended daily intake and upper limits for dietary supplements to ensure that the supplements you’re taking won’t interfere with other supplements. “Consult with your doctor or nutritionist to determine your specific nutritional needs,” Rose suggests.
“It’s a common misconception that vitamin supplements are beneficial for everyone,” Messer says. “While they may be beneficial to certain individuals in certain situations, they are not universally necessary, can be costly, and are not completely risk-free.”
