Carrie Underwood Admits Taking Diet Pills After ‘American Idol’: Here’s Why They’re So Bad for You

Carrie Underwood walks the red carpet at the 2015 CMT Music Awards in June 2015. The singer revealed that after winning “American Idol” in 2005, she turned to diet pills to lose weight. (Photo: Getty Images)

Carrie Underwood made a surprising confession in a new interview with People: She used controversial supplements to lose weight after she won American Idol.

The 32-year-old singer says she turned to supplements 10 years ago to lose weight after getting compliments when she made “little tweaks” to her diet.

“I was taking things with ephedra in it,” she says in the interview. “It wasn’t the best way. If I could go back and talk to myself I’d be like, ‘Here’s how you do it the right way.’”

Underwood performing on “American Idol” on May 17, 2005. (Photo: Getty Images)

Ephedra is an herb that is used to treat colds and headaches in alternative medicine circles, but it’s also sometimes marketed for weight loss. The Food and Drug Administration banned the sale of products containing ephedra in 2003, but they can still be easily purchased online.

According to the Harvard School of Public Health, ephedra has been linked to more than 800 dangerous side effects such as heart attacks, strokes, psychosis, insomnia, seizures, and sudden death.

A study published in the Annals of Internal Medicine also found that, while ephedra products make up just 1 percent of herbal supplement sales in the U.S., they’re responsible for 62 percent of all herb-related reports to poison-control centers.

While it seems like Underwood didn’t suffer major negative health consequences, experts stress that it’s never a good idea to take weight-loss supplements.

“Many supplements are both ineffective and potentially unsafe,” Alissa Rumsey, registered dietitian and spokesperson for the Academy of Nutrition and Dietetics, tells Yahoo Health.

The supplement industry is largely unregulated by the FDA, making it difficult to know if the supplements will actually do what they claim they will do, and even if they contain the ingredients they claim to contain.

Using these products can negatively impact a person for years. Registered dietitian nutritionist Beth Warren, author of Living a Real Life With Real Food, tells Yahoo Health that she’s seen patients abuse these pills, leading to addiction, poor perceptions of body image, and bad dietary and lifestyle habits.

And often, they don’t even work. “Most studies show no significant difference in weight loss between people who take supplements versus those taking a placebo,” says Rumsey.

Warren agrees, adding that the effects of weight-loss supplements would be short-lived at best. “Each one has a different mechanism that enables them to perhaps help lose weight, such as blocking fat absorption, or simply speeding up the metabolism (i.e. caffeine pills),” says Warren. “But ultimately, they would be short-term results, if any at all.”

Related: FDA Issues Warning On Weight Loss Supplements Containing Dangerous ‘Super Caffeine’

The same applies to supplements that are marketed as “herbal” or “natural.”

“Even though it’s herbal, doesn’t mean it’s safe,” Warren says. “They can sometimes be more dangerous because people assume that, since the pills are natural, they won’t have any ill effects.” But, she adds, a lot of herbs mimic drug behavior inside the body and can interact with a lot of medical conditions and medications in a negative way.

Indeed, a recent study shows that dietary supplements send 23,000 people to the hospital each year, with many of those supplements claiming to be herbal and natural.

Related: Dietary Supplements Send 23,000 to the Hospital Every Year

Since these supplements are largely unregulated, there’s a high risk of contamination and mislabeling, Rumsey says, noting that some “natural” supplements have even been found to contain anti-anxiety medication.

Another problem is that several of the companies that sell these weight loss supplements may be located outside of the U.S. “If there is an adverse reaction, these companies may be out of the country and may not have the resources to fix the problem their pills caused,” Gina Keatley, a certified dietitian-nutritionist practicing in New York City, tells Yahoo Health. Meaning, it’s possible to buy pills that have caused health issues for others and not even know about the issue.

You’ve heard it before, but experts stress the best, safest, and longest-lasting way to lose weight is by making healthy modifications to your diet and exercise regime.

“Include more vegetables, fruits, whole grains, and lean protein in your diet, and cut down on highly processed foods, trans fats, and sugar consumption,” says Rumsey.

And keep in mind that, if it sounds too good to be true, it probably is. “We all want quick fixes, but they can be harmful and short term,” Warren says.

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