What Are Collagen Supplements?

Collagen is a structural protein found in connective tissues throughout your body, including skin, bones, tendons, and ligaments. Its primary function is to help tissues withstand stretching. As you age, your body make less collagen. Some people attempt to restore collagen by taking collagen supplements.

Researchers have investigated the effects of collagen supplementation on aging skin, bone density, joint health, and other factors. While results are promising, more research is needed to fully understand whether or not supplementation is effective.

Does Collagen Have Any Benefits?

Despite claims that collagen supplements can firm up your skin, fight age-related damage, boost bone health, and provide other benefits, few rigorous independent studies have tested the effects of these supplements.

Here are some findings from the available research.

Skin

Collagen makes up 75% of the dry weight of your skin. As you age, your skin's inner layer loses collagen and becomes less supple and more vulnerable to damage.

In a 2015 study, scientists evaluated whether or not supplementation could improve the collagen density of skin tissue in a lab setting. Their results suggested that supplements could improve both skin hydration and the dermal collagen network with the potential to improve hallmarks of skin aging.

Other studies have investigated skin elasticity, which starts to decline in your 20s. In a 2014 study in Skin Pharmacology and Physiology, for instance, women ages 35 to 55 took a specific collagen supplement or a placebo once daily for eight weeks. At the study's end, those who took the collagen had improved skin elasticity compared to those who took the placebo.

A 2018 study published in Nutrition Research investigated the role of a specific brand of oral collagen supplement that also contained other ingredients (chondroitin sulfate, glucosamine, L-carnitine, vitamins, and minerals). Researchers found that the supplement increased skin elasticity and hydration.

Lastly, a 2019 review of studies investigating oral collagen supplements evaluated their effects on wound healing and skin aging. Study authors concluded the supplements are generally safe and can increase skin elasticity, hydration, density. They added, however, that further studies are needed to determine proper dosing and investigate medical applications.

Bone Health

It is unclear whether collagen supplementation can improve bone health.

In a 2010 study published in the journal Maturitas, researchers found that collagen supplements failed to improve bone health in postmenopausal women. For the study, 71 women with osteopenia were assigned to take either hydrolyzed collagen supplements or a placebo every day for 24 weeks. Results revealed that the collagen supplements did not produce any effects on bone metabolism.

But a 2018 study published in Nutrients concluded that the intake of a specific brand of collagen peptide increased bone mineral density in postmenopausal women. In addition, supplementation was associated with a favorable shift in bone markers, indicating increased bone formation and reduced bone degradation.

Body Composition

Some people may take collagen to preserve muscle mass or decrease fat mass. Studies on this are limited and have provided mixed results.

A 2019 study published in Nutrients investigated whether or not collagen supplementation combined with resistance training could affect body composition in active men. Fifty-seven men participated in a 12-week program that combined resistance training with either consumption of a collagen supplement or consumption of a placebo. Researchers found that both groups increased muscle to the same extent. However, those who took a collagen supplement showed a slight increase in fat-free mass, thought to be related to improvements in connective tissue.

Another small trial compared hydrolyzed collagen protein supplements to whey protein supplements in older women. The 2009 study published in the Journal of the American Dietetic Association found that taking hydrolyzed collagen supplements may help preserve lean body mass.

Joint Pain

Collagen helps stimulate the production of cartilage—a rubbery material that covers and protects bones and helps joints move smoothly. Collagen and cartilage production declines with age. There is some evidence that collagen supplements may reduce joint pain and other symptoms of osteoarthritis.

In 2019, researchers evaluated studies that investigated the effects of collagen supplements on osteoarthritis symptoms. The meta-analysis published in International Orthopaedics concluded that collagen is effective in reducing stiffness associated with the condition. It was less effective at reducing pain and functional joint limitation.

Heart Disease

Some people take collagen supplements to boost heart health, although there is limited independent research to support this benefit.

Researchers affiliated with a Japanese company that makes a collagen-based functional foods published a study in 2017. They concluded that when consumed regularly for six months, collagen tripeptide helped improve cholesterol levels and reduced other risk factors for atherosclerosis (hardening of the arteries).

Other Uses

Some consumers also take collagen supplements for eye health, to improve the appearance of skin and nails, and to encourage weight loss. However, little evidence is available to support these benefits.

Possible Side Effects

There are some reports that collagen supplements may cause mild digestive symptoms or a bad taste in the mouth.

There's also some concern that stimulating collagen synthesis can also increase oxidative stress and reactive oxygen species (ROS) production.

Those with a fish, shellfish, or egg allergy should avoid collagen supplements as many of them are made from these ingredients.

Collagen supplements haven't been tested for safety. Keep in mind that the safety of supplements in pregnant women, nursing mothers, children, and those with medical conditions or who are taking medications has not been established.

Some collagen products have been recalled by the U.S. Food and Drug Administration (FDA) because of false claims. Products that stimulate collagen production or claim to remove wrinkles are considered drugs (rather than supplements) by the FDA. These products must provide evidence of safety and effectiveness. If no evidence or insufficient evidence is provided, they are removed from the market.

Dosage and Preparation

Collagen supplements are available in the form of tablets, capsules, and powders.

Dosage recommendations vary. Studies investigating the benefits of collagen supplements have evaluated doses ranging from 2.5 to 10 grams per day. However, some supplement makers and other proponents of collagen-based products recommend up to 30 grams per day.

Your healthcare provider may be the best source of advice to determine the proper dose for you.

Note that you can also boost collagen production by consuming foods such as bone broth or pork skin.

What to Look For

Many products marketed as collagen supplements contain hydrolyzed collagen, which is animal-derived collagen that has been broken down into small peptides so that your body can absorb it more effectively.

Because collagen supplements are usually made from fish scales, cow bones, or other animal parts, those who follow a strict vegan diet may want to find an alternative.

Lastly, keep in mind that a more expensive supplement is not necessarily a better one.

Other Questions

What about collagen creams. Do they work?
There is currently a lack of scientific evidence for the anti-aging effects of creams, lotions or other beauty products containing collagen. But experts note that creams are the least likely form of collagen to be effective because it is hard to absorb it through the skin.

Are collagen injections safe?
One type of cosmetic procedure involves injecting certain substances ("fillers") into the skin in order to reduce signs of aging, such as fine lines. Poly-L-lactic acid fillers, for instance, help fight the effects of aging by stimulating collagen production in the skin. Although fillers are generally considered safe, they sometimes lead to side effects like skin discoloration and allergic reactions. What's more, the anti-aging effects of these procedures are temporary and require repeat treatments to maintain results.