7 Surprising Side Effects Of Drinking Collagen That You Need To Know


Collagen supplements have become increasingly popular over the last several years, moving from a fringe supplement to one that's more and more recognizable, with your favorite wellness bloggers posting about it and your friends and coworkers adding it to everything from their morning cup of coffee, to their smoothies. But as it continues to get more and more popular, you might wonder how safe and effective it really is. If you're already drinking (or eating) collagen or want to get in on the trend, there are some surprising side effects of drinking collagen that you need to know.

First off, collagen is a connective tissue that you naturally produce in your body. It's more difficult to produce enough collagen as you age, however, so some people turn to other sources (like supplements and cosmetic procedures) to get what they're hoping are some of the same effects that they'd get from the collagen their body produced.

"Collagen protein fills a gap in the modern day diet; it is not just a flash in the pan," Pamela Schoenfeld, MS, RD, LDN, a registered dietitian and author of The Collagen Diet: Rejuvenate Skin, Strengthen Joints and Feel Younger by Boosting Collagen Intake and Production, tells Romper by email. "You don't have to buy collagen protein in powder form. Foods like bone broth, gelatin desserts and salads, oxtail soup, short ribs, and chicken wings are great sources."

Still, if you're going to use a powdered collagen (or another form of the supplement), which Schoenfeld says can be easiest and most effective, it's a good idea to know what sorts of side effects might come along for the ride.

1. Collagen Might Help Ease Joint Pain

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Mark Moyad, MD, director of the complementary and alternative medicine program at the University of Michigan Medical Center, told Web MD that “many of the studies done so far on collagen are small and at least partially funded by industry,” but, as the site reports, he finds finds “the evidence suggesting it may improve body composition, joint health, and healing rates intriguing.”

Schoenfeld, for her part, tells Romper that many people who use collagen peptides for about two to four months can see some benefits in terms of joint pain, so if that's something with which you struggle, it might help you too. Plus, a 2008 study from researchers at Penn State University found that collagen might help lessen or prevent joint pain in people who otherwise don't have any sort of joint disease.

2. It Might Help Improve Your Skin — Or Maybe Not

Dora Vandekamp, a nutritionist and natural beauty expert, tells Romper by email that collagen can help your skin — and Schoenfeld agrees. In fact, many people who regularly consume a collagen supplement say that they notice improvements in their skin, but some dermatologists doubt that it would really have an effect. There is some scientific evidence that collagen might help improve skin; for example, a couple of 2014 studies showed that women who took collagen showed an improvement in skin elasticity, while control subjects who took placebos did not.

3. It May Help Your Digestive System

Vandekamp notes that collagen can also help boost gut health, so if you have gut issues, it might be something to look into. And in a post on his website, Dr. Josh Axe, DNM, DC, CNS, a certified doctor of natural medicine and a clinical nutritionist, wrote that collagen might help with conditions like leaky gut.

However, it's safe to say that collagen's effect on the gut is another area where more research is needed.

4. It Might Be Able To Boost Hair & Nail Growth

Schoenfeld says that, in addition to an improvement in joint pain, many people regularly consuming collagen also notice an increase in hair and nail growth. Dr. Barry Sears, PhD, the creator of the Zone Diet, also tells Romper by email that collagen is a good source of proline, which is the primary amino acid your body needs for hair and nail formation.

However, "ingestible collagen, such as in shakes, supplements, or powders, does not have any major proven benefit over ingesting any other form of protein," Rachel Nazarian, MD, a New York-based dermatologist and Fellow of the American Academy of Dermatology (FAAD), told Health.com.

5. Collagen Might Improve Your Ability To Heal Wounds

A 2006 study published in the journal Advances in Skin & Wound Care found that taking collagen over the course of eight weeks sped up healing of pressure ulcers in residents long-term care facilities. The study was small, but the results are intriguing.

6. There Are Concerns About Heavy Metals & Other Undesirable Things

If you're going to use a collagen supplement (or any other supplement), like with anything else, it's important to do your research. "It is important to source your collagen from an organic and reputable source, as recent laboratory tests revealed that contaminants such as antibiotics, parabens and steroids were found in popular collagen products," Vandekamp says. "Doing your own personal research is imperative."

Schoenfeld agrees. "There is some evidence that if animals are fed foods high in a certain pesticide it could concentrate in the collagen protein," she explains.

Plus, as Moyad told WebMD in the aforementioned article, the parts of animals used to create collagen supplements can be high in heavy metals. So it's important to make sure that the company you choose tests for that. And WebMD also reported that some experts are concerned about the potential for bovine spongiform encephalopathy (aka mad cow disease), but Duffy MacKay, a naturopathic doctor, told WebMD in the same that reputable collagen companies request that their suppliers certify that their animal products are BSE-free.

7. It Might Increase Your Risk Of Kidney Stones

If you have a history of kidney stones, you might want to steer clear from collagen or enlist your doctor for guidance. "If you have a history or a family history of kidney stones, start with a small amount of collagen protein as for some people it could increase their likelihood for kidney stones," Schoenfeld says. "You can gradually increase, but caution is advised."

That's because a diet high in animal proteins in general can be a factor in kidney stones, as noted by Harvard Medical School's site, Harvard Health. "Eating too much animal protein, such as red meat, poultry, eggs, and seafood, boosts the level of uric acid and could lead to kidney stones," Harvard Heath reports. "A high-protein diet also reduces levels of citrate, the chemical in urine that helps prevent stones from forming."

All in all, the research is still out on collagen in some respects, but some experts wholeheartedly endorse its use, as long as you do your research and make sure you're choosing a high-quality product. Knowing what you're getting into can help prevent any surprises and give you another option if you're dealing with something that collagen might be able to help.

Studies referenced:

Clark, K. L., Sebastianelli, W., Flechsenhar, K. R., Aukermann, D. F., Meza, F., Millard, R. L., Albert, A. (2008). 24-Week study on the use of collagen hydrolysate as a dietary supplement in athletes with activity-related joint pain. Current Medical Research and Opinion. Retrieved from https://www.ncbi.nlm.nih.gov/pubmed/18416885

Lee, S. K., Posthauer, M. E., Dorner, B., Redovian, V., & Maloney, M. J. (2006). Pressure Ulcer Healing with a Concentrated, Fortified, Collagen Protein Hydrolysate Supplement. Advances in Skin & Wound Care. Retrieved from https://www.ncbi.nlm.nih.gov/pubmed/16557055


Pamela Schoenfeld, MS, RD, LDN, registered dietitian and author of The Collagen Diet: Rejuvenate Skin, Strengthen Joints and Feel Younger by Boosting Collagen Intake and Production

Dora Vandekamp, nutritionist, natural beauty expert, and host of Biohack Your Beauty podcast.

Dr. Barry Sears, PhD, biochemist, author, and creator of the Zone Diet.

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