10 Things To Consider Before Taking Collagen Supplements

Prepare for possible gut woes.

by JR Thorpe and Carolyn Steber
Originally Published: 
Dermatologists explain the different side effects of taking collagen supplements to consider before ...

Many people sing the praises of collagen, saying it can improve the health of your skin, hair, nails, and bones. Still, it’s a good idea to look into possible collagen supplement side effects and other concerns before adding it to your daily routine.

Collagen is a protein that helps to serve as one of the main building blocks for skin, hair, muscles, tendons, ligaments, and bone,” says board-certified dermatologist Dr. Anna Chacon, M.D. Taking it in supplement form may help improve bone density, she says, prevent bone loss, and improve joint health. And then there are many purported beauty benefits as well (hence why you’ll see it in countless hair and skin-boosting ingestibles).

Collagen supplements have been marketed as a way to "turn back to the clock," Dr. Blair Murphy-Rose, M.D., a board-certified dermatologist, tells Bustle. "Some small studies have shown increased elasticity and hydration in the skin after subjects consumed collagen supplements over eight to 12 weeks compared to a control group. However, scientific data is still limited and inconclusive at this point."

For the most part, collagen supplements are considered safe to consume without any serious side effects, says Dr. Stacy Chimento, M.D., a board-certified dermatologist at Riverchase Dermatology. For some people, however, it can cause some discomfort, as you’ll see below. But it’s also important to know that collagen may not be the “wonder” supplement many folks paint it to be.

Board-certified dermatologist Dr. Erum N. Ilyas, M.D., MBE, FAAD, says to take what you read on product packaging with a grain of salt. “Be cautious with regards to marketing language,” she warns. “Things that sound too good to be true usually are.” Here, dermatologists break down the 10 most important things to know about collagen supplements before you decide to buy them in bulk.


There Are Many Different Types Of Collagen

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"Some people may feel mild bloating or heaviness in their stomach," Chimento says. As your body's stomach acids break down the collagen in supplements, you might experience some wind, queasiness, or a feeling of weight in your abdomen. This should pass relatively quickly, as it's part of the digestive process.


Collagen Might Make You Feel Bloated

If you feel uncomfortable after taking a collagen supplement, know that you aren’t alone. "Some people may feel mild bloating or heaviness in their stomach," Chimento says. As your body's stomach acids break down the collagen in supplements, you might experience some wind, queasiness, or a feeling of weight in your abdomen. This should pass relatively quickly, as it's part of the digestive process.


If You're Allergic To Seafood Or Eggs, It Could Trigger A Reaction

If you have a food allergy, collagen supplements might not be for you. "Some are made from seafood or eggs, so if patients have a shellfish or egg allergy, this is something to look out for," Chimento says. If you break out in a rash or have any mild allergic reactions after taking a collagen supplement, take an anti-histamine and consult an allergist. Serious allergic reactions like breathing difficulties mean you need to go to the ER, ASAP.


It Might Not Be Vegan

Many collagen supplements aren't vegetarian or vegan.

If you’re vegetarian or vegan, it’s important to know that some collagen can be extracted from fish like cod or mackerel or derived from the membranes of eggshells. Luckily, there are vegan versions that come from sources like algae, so be sure to look at sourcing before you buy your box of supplements.


Other Unknown Ingredients Might Cause Problems

"Before you take collagen supplements, it is also important to research the brand you are buying and make sure you are taking something that is quality," says Murphy-Rose. Collagen supplements are classified as dietary supplements, so they aren't regulated by the FDA, and that could mean it includes ingredients you don't want. Always talk to your doctor before taking a supplement; they may be able to recommend trusted brands that are known to be high-quality.


You Could Feel Constipated

Collagen supplements have the potential to block you up. "Too much protein without enough fiber and fluid can lead to constipation," Vanessa Rissetto, RD, a registered dietitian nutritionist and co-founder of nutrition coaching service Culina Health, tells Bustle.


You Might Experience Diarrhea

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Need to go to the bathroom immediately after taking your morning supplements? The collagen could be to blame. Chimento says diarrhea is listed as one of the rarer side effects of collagen.

Chalk both diarrhea and constipation up to the body attempting to process a lot of collagen proteins. If your gastrointestinal system is having a rough time dealing with your supplements, it could be a sign to take fewer or stay away from them altogether.


It Could Interact With Other Drugs

"Patients should consult with their doctor before taking collagen supplements to rule out any interactions with medications or supplements already in your daily regimen," Chimento warns.

As an example, some wound-repair gels containing collagen are known to interact poorly with certain topical anesthetics. Chatting to your doctor is particularly important if you experience any digestive problems when it comes to collagen supplements, as it might prevent the active ingredients in your medication from being fully absorbed in your stomach.


It Won’t Show Results Right Away

While you may be crossing your fingers for longer hair or stronger nails after taking collagen, you definitely won’t see any benefits overnight. A 2019 study published in the Journal of Drugs In Dermatology found that it can take up to 12 weeks for collagen peptide supplements to show a notable improvement in skin elasticity and hydration, so it’ll call for consistency and patience.


It Might Not Even Do Anything

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All of that said, you might not notice a difference in how you look or feel, even after taking collagen for a couple of months. “Actual benefits to oral collagen supplementation are unclear and lack evidence,” says dermatologist Dr. Sheilagh Maguiness, M.D., adding that many studies are funded by companies and therefore may be biased.

And, remember, supplements and nutraceuticals in the U.S. are not regulated by the FDA. “For those individuals looking for ways to improve the quality and texture of their skin, evidence-based topical therapies such as sunscreen and topical retinoids might be safer and more cost-effective options,” says Maguiness.

You can also boost your body's natural production of collagen by eating certain nutrients. Murphy-Rose suggests eating more foods that contain vitamin C, A, copper, and proline. "That will supplement collagen formation," she says. And that can mean happier skin, muscles, and bones.

Studies referenced:

Bolke, L., Schlippe, G., Gerß, J., & Voss, W. (2019). A Collagen Supplement Improves Skin Hydration, Elasticity, Roughness, and Density: Results of a Randomized, Placebo-Controlled, Blind Study. Nutrients, 11(10), 2494. https://doi.org/10.3390/nu11102494

Choi, FD. (2019). Oral Collagen Supplementation: A Systematic Review of Dermatological Applications. J Drugs Dermatol. 2019 Jan 1;18(1):9-16. PMID: 30681787.

Deane, C.S. (2020). Animal, Plant, Collagen and Blended Dietary Proteins: Effects on Musculoskeletal Outcomes. Nutrients. https://www.ncbi.nlm.nih.gov/pmc/articles/PMC7551889/

König, D. (2018). Specific Collagen Peptides Improve Bone Mineral Density and Bone Markers in Postmenopausal Women-A Randomized Controlled Study. Nutrients. 2018 Jan 16;10(1):97. doi: 10.3390/nu10010097. PMID: 29337906; PMCID: PMC5793325.

León-López, A. (2019). Hydrolyzed Collagen-Sources and Applications. Molecules (Basel, Switzerland), 24(22), 4031. https://doi.org/10.3390/molecules24224031.

Mei, F. (2020). Effect of a high-collagen peptide diet on the gut microbiota and short-chain fatty acid metabolism. Journal of Functional Foods. Volume 75, December 2020, 104278. https://doi.org/10.1016/j.jff.2020.104278

Rustad A.M., (2021). Myths and media in oral collagen supplementation for the skin, nails, and hair: A review. J Cosmet Dermatol. 2021 Oct 25. doi: 10.1111/jocd.14567. Epub ahead of print. PMID: 34694676.


Dr. Anna Chacon, M.D., board-certified dermatologist

Dr. Stacy Chimento, M.D., board-certified dermatologist

Dr. Erum N. Ilyas, M.D., MBE, FAAD, board-certified dermatologist

Dr. Blair Murphy-Rose, M.D., board-certified dermatologist

Vanessa Rissetto, RD, registered dietitian nutritionist

Dr. Sheilagh Maguiness, M.D., dermatologist

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