Sunscreen comes in many forms, from lotions to sprays to sticks, but the Food and Drug Administration (FDA) is warning consumers to steer clear of one formula in particular--the so-called "sunscreen pills."

You know how it goes, you burn, but it eventually turns into a tan. The response is the body's natural defense against the sun's ultraviolet rays.

Even so, repeated exposure to UV rays can damage your skin and eventually lead to everything from premature aging to cancer.

Skin cancer is the most common type of cancer in the United States. Reports show that one in five Americans are at risk of developing skin cancer in their lifetime.

Traditional sunscreens block ultraviolet light before it hits your skin, helping to reduce the amount of damage UV light can do.

While sunscreens protect us from the outside, sunscreen pills are one of the newest trends in sun protection. They're oral supplements containing vitamins and strong antioxidants that claim to protect skin cells from the sun's harmful rays from inside the body.

However, according to the FDA there's no such thing as a sunscreen pill. The FDA said you could be putting yourself at an increased risk of sunburn or skin cancer if you're misusing them.

So what exactly about these pills concern us?

It's not a specific ingredient in the pills rather it's the marketing. The federal agency accused four brands Advanced Skin Brightening Formula, Sunsafe Rx, Solaricare and Sunergetic of misleading advertising. They said these claims are not necessarily true and give consumers a false sense of security.

Dermatologists are concerned people will believe the pills will protect them from the sun and be less inclined to apply a topical sunscreen.

“The main point that needs to be stressed is people should be smart about sun exposure and use as many tools available to them to protect themselves, not just one. In this instance more is truly better,” said Dr. Scott A. Smith, Valley Dermatology.

"There's no pill or capsule that can replace your sunscreen," said FDA commissioner Dr. Scott Gottlieb.

Companies can legally sell the products at major pharmacies without FDA regulation and oversight because these manufacturers call their products "nutritional supplements" instead of drugs. The supplement industry is protected by federal legislation called the Dietary Supplement Health and Education Act of 1994. The FDA can only step in when a company makes a medical claim for its product, as in this case.

The American Academy of Dermatology does say the antioxidants and ingredients found in sun pill supplements have been shown to offer protective effect from sun damage, but there is no research to support their effectiveness when combined.

Unlike the sun pills, conventional sunscreens must pass certain tests before they're sold and have been proven safe and effective.

“These supplements may help reduce some of the damage by the suns harmful rays but the main point that needs to be stressed is that these are likely relatively safe to take but should not be the only sun precaution that people use,” said Dr. Scott A. Smith, Valley Dermatology.

The FDA recognizes the growing evidence that suggests some sunscreen may be absorbed through the skin and is also supporting new research and regulations related to the safety and delivery of the active ingredients in conventional sunscreens.