The way it’s marketed, collagen sometimes sounds less like a supplement, and more like the fountain of youth. Purported benefits of collagen — a major structural protein in the body — range from glowing skin to strong nails and voluminous hair (although Harvard Medical School says large-scale trials are still needed to prove its hair health benefits). Proponents on social media call collagen powder their “secret” to good hair and skin, speaking to its efficacy, and encouraging others to give it a try. But before jumping on the bandwagon yourself, it pays to know a little about collagen side effects.
While collagen may work for some, there are some things to consider before adding it to your daily routine. To make it easier, we asked experts to help unpack potential collagen side effects, from common complications to rare health issues. Read on to learn more, and see if collagen supplements are actually worth the risk.
Experts Featured in This Article:
Jordan Wagner, DO, is a board-certified emergency medicine physician with over a decade of experience in the emergency room.
Whitney English, MS, RDN, is a registered dietitian nutritionist and journalist with over ten years reporting in the health and wellness space.
Collagen Basics
Collagen is often touted as a beauty secret, but it’s more than skin-deep. Some studies suggest collagen supplements may help improve heart health, reduce joint pain, and increase muscle mass, which explains why it’s such a popular supplement.
For context, there are multiple different types of collagen, but some are more common than others. One of the most popular varieties is called hydrolyzed collagen, which is often referred to as “collagen peptides.” According to GoodRx, hydrolyzed collagen is extracted from animal sources and broken down into smaller particles for easier absorption. While collagen is technically only produced by humans and animals, there’s also vegan collagen, which claims to support the body’s natural collagen production (although the research here is much more scarce).
Collagen Side Effects
While collagen supplements are sold in many forms, from collagen powder to collagen gummies, the side effects are essentially the same, says Jordan Wagner, DO. “Some studies have reported mild to moderate gastrointestinal disturbances [from collagen],” says Whitney English, MS, RDN. Here’s a comprehensive list of the more common collagen side effects (most of which are quite mild):
- Gas
- Heartburn
- Nausea
- Abdominal Pain (Dyspepsia)
- Bloating
In rare cases, collagen can also be a trigger for kidney stones, due to the amino acid hydroxyproline. Marine-based collagen may also put you at a higher risk for hypercalcemia (excessive calcium) which can cause an abnormal heart rhythm. Dr. Wagner also points to three reported side effects, all of which are due to contaminants in collagen supplements as opposed to the collagen itself. These side effects are considered rare, but they’ve been reported enough times for the Food and Drug Administration (FDA) to recall a number of leading collagen supplements on the market.
- Mad Cow Disease: Mad cow disease is a virus transmitted through contaminated nerve tissue and bones, explains English. Thankfully, while some collagen is derived from cows, companies typically use cow dermis (not the central nervous system where mad cow disease is usually found, per Collagen Solutions). So this one’s more of a theoretical risk. That said, both experts still recommend carefully researching the ingredients in your collagen powder or supplement.
- High Calcium: As previously mentioned, certain forms of collagen may increase your calcium levels, which can lead to frequent urination, upset stomach, vomiting, confusion, fatigue, and heart issues, per the Mayo Clinic.
- Arsenic Poisoning: Although a previous study detected heavy metals like arsenic in collagen products, more recent research shows that commercial collagen products have generally improved. In a 2023 study of 10 of the most popular collagen products (animal-based), no lead, mercury or arsenic residues were found in any of the tested samples.
Are Collagen Supplements Worth the Risk?
Regardless of the side effects, neither Dr. Wagner nor English are huge fans of collagen supplements — the primary reason being that they’re not entirely necessary. “Collagen is the most abundant protein in our body, accounting for about a quarter to a third of the protein composition,” Dr. Wagner says. “It’s hard to escape an Instagram feed without spotting collagen creams, drinks, and potions,” he acknowledges. But while these supplements are trendy among influencers, the medical implications shouldn’t be taken lightly.
The bottom line? If you’re considering taking a collagen supplement, this should be a decision between you and your doctor — not you and the influencers you follow.
— Additional reporting by Chandler Plante
Kalea Martín writes primarily about food and cooking for PS, but as a former figure skater and hockey player, she covers fitness, too. Prior to becoming a lifestyle writer, Kalea covered hotels, restaurants, and travel for Luxos Magazine in Milan and worked in marketing at HarperCollins Publishers.
Chandler Plante is an assistant editor for PS Health & Fitness. Previously, she worked as an editorial assistant for People magazine and contributed to Ladygunn, Millie, and Bustle Digital Group. In her free time, she overshares on the internet, creating content about chronic illness, beauty, and disability.