What Really Happens to Your Body When You Take Collagen

If you don't take collagen, you probably know someone who does. It's one of the most popular supplements around, and its demand is growing, according to a release from the market research company Grand View Research.

And it makes sense: Collagen's health claims are pretty impressive — from stronger bones to glowing skin to healthy joints, it really seems to do it all.

But before you blow through your savings account in search of the fountain of youth in the supplement aisle, you should know not all of the claims about collagen are scientifically sound. It's true that collagen is important for healthy skin, nails, hair and bones, but you may not need a collagen supplement if your diet is already filled with healthy sources of protein.

Collagen is the most abundant protein in the human body. It's found in your bones, skin, muscles, blood vessels, intestinal lining and tendons. Collagen is classified into three types:

• Type I and III are found in the skin, tendons, organs and bones.
• Type II is the collagen found in cartilage, so it makes sense for this to be the focus of much of the research surrounding collagen and arthritis, per the Arthritis Foundation.

Because it's a protein, collagen is made up of amino acids. When proteins are broken down after you eat, the amino acids join an amino acid pool in the body and the body decides where those amino acids should go, and collagen works the same way. Collagen is high in three specific amino acids — proline, hydroxyproline and glycine — which are necessary for collagen synthesis in the body, per a November 2019 study in ‌Cellular and Molecular Life Sciences‌.

The structure of collagen is similar to a rope, and it holds similar qualities of a rope, strong and tight. But as you get older, your production of collagen decreases as part of the natural aging process and due to other things like diet and chronic stress.

Although you can't prevent the natural loss of collagen, you can add the protein to your diet in the form of a supplement. Here's what the science has to say about the collagen benefits for your body.

Research done over the past several years has found numerous collagen benefits, particularly for your skin, nails, joints and muscles.

Because your body's natural ability to produce collagen decreases as you age, supplementing with collagen peptides can help to replace your body's stores.

The benefits of hydrolyzed collagen supplements for your skin have been the most extensively studied. Collagen has been shown to improve skin elasticity, reduce dryness and improve the depth of wrinkles, according to a July 2020 review in ‌Experimental and Therapeutic Medicine‌.

We make less collagen as we age, so that makes our skin seem, well, droopy. Beyond age, there are additional factors that accelerate the aging process, including excessive exposure to sunlight, smoking and eating an unbalanced diet, according to October 2019 research in ‌Nutrients.‌

In the study, researchers examined the effects of 2.5 grams of collagen peptides on 72 women, age 35 and older, against a placebo for three months. They found no collagen side effects and the results were significant: The women who took the collagen peptides reported more elasticity, more skin hydration, less roughness and better appearance.

Even further, researchers found that collagen supplements improve wound healing and skin aging during a January 2019 systematic review of 11 studies in the ‌Journal of Drugs in Dermatology‌. Collagen was shown to also increase skin elasticity, hydration and collagen density, with no reported side effects.

Still, the studies were small, and additional research is needed to identify the proper doses of collagen supplements, the report concluded.

To prevent osteoporosis or reduced bone loss, older adults are advised to get adequate amounts of calcium and vitamin D, as explained by the Mayo Clinic. Collagen may soon be added to that list, as research suggests it may have the benefit of improving bone mineral density.

For example, in a study of 102 postmenopausal people, half received 5 grams of collagen peptides and half received a placebo, per the January 2018 research in ‌Nutrients‌. After 12 months, researchers saw significantly increased bone mineral density in the lumbar spine and femoral neck in the people taking collagen. The same was not seen in the people taking a placebo.

While arthritis can occur because of many factors, the deterioration of cartilage is a key indicator of the condition, according to the Mayo Clinic.

"Some studies show collagen can improve joint health and reduce perceived pain and be soothing to the gut as well," says Holley Samuel, RD, who counsels athletes on good nutrition practices.

For three months, 20 people with knee osteoarthritis were given acetaminophen and type II collagen while another group was given just acetaminophen, per the June 2016 study in the‌ Eurasian Journal of Medicine‌. The group taking type II collagen reported less joint pain and improved function over the group who were not given the collagen.

As researchers stated in the journal ‌Amino Acids‌ in September 2021, "Collagen is most beneficial in improving joint functionality and reducing joint pain."

Collagen is found in muscles, tendons, ligaments, organs, blood vessels and skin, so it's pretty important, according to the Cleveland Clinic.

This also means that supplementing the amount of collagen going into the body can help strengthen muscles and even promote their regrowth.

In fact, people who took collagen supplements showed more muscle strength and growth after exertion from exercise, according to an October 2015 study in the ‌British Journal of Nutrition‌.

There are no definite clinical studies, as of yet, that show collagen supplements play a direct role in helping people lose weight, but there are several factors that may aid the process.

Thanks to its role in muscle growth, supplementary collagen means the body requires more energy than it ordinarily would, and this acts to burn calories, according to the October 2015 ‌British Journal of Nutrition‌ study. In addition, the increased energy will also accelerate the body's metabolic rate to improve the digestive system and encourage weight loss.

Collagen supplementation was shown to act as an appetite suppressor in a study of estrogen-deprived rats, according to research published in the ‌International Journal of Medical Sciences‌ in October 2016. However, more research is needed in order to support collegen's effects on hunger and weight loss in humans.

You can get collagen from foods like bone broth, but it's available in supplements that you can take in powdered or pill form.

Collagen supplements come in a form called collagen peptides (also referred to as hydrolyzed collagen), which are a form of collagen that has been broken down through a process called hydrolyzation, according to the Harvard T.H. Chan School of Public Health. Hydrolyzation is a fancy term that means "to break apart with the addition of water."

When collagen is hydrolyzed, it breaks down into smaller molecules that are more easily absorbed by your body, according to the Harvard T.H. Chan School of Public Health. Collagen peptides are water-soluble, so they completely dissolve in both hot and cold liquid, and they're tasteless (unless you choose a flavored variety). You can stir them into your water or blend them into your protein smoothies without affecting the taste or texture.

The majority of hydrolyzed collagen comes from one of the following sources, per a November 2019 study in ‌Molecules‌:

• Cow tissues and tendons (bovine collagen)
• Pig skin
• Chicken bones
• Fish (marine collagen)

Unfortunately, these sources don't bode well for vegans and vegetarians hoping to reap the benefits of collagen. You may see "vegan collagen" that is made from yeasts and bacteria, but there is no evidence that this works in the same way as animal collagen.

Your dosage requirements depend on which type of collagen you are taking.

Typically, type I collagen is hydrolyzed collagen and the dose is anywhere between 5 to 15 grams per day, usually in powdered form, . This makes it easy to stir into drinks, mix with your smoothie or bake into muffins. Type II dosage is a little different and in smaller amounts, typically measured in milligrams instead of grams.

"I recommend mixing powdered collagen with something like a fruit smoothie or oats with fruit so there's a source of vitamin C to improve absorption," Samuel says. Vitamin C is found in foods like tomatoes, oranges and strawberries.

Collagen is usually well tolerated with few side effects, but you should always give a quick call to your doctor and let them know about any supplements you plan to take and get the OK.

Collagen supplements come in a variety of forms, but the two most notable and readily available are collagen powder and collagen pills or capsules. There are several factors to consider before deciding which is best for you.

Hydrolyzed collagen (also known as collagen peptide) is the most commonly featured in medical studies into the effectiveness of collagen supplements. The Cleveland Clinic describes collagen peptide as a powder that ordinarily has no flavor and dissolves easily into beverages or smoothies, making it easy to take.

Collagen pills or capsules are not too different, only they are usually supplemented with other vitamins and minerals to form the tablet or capsule. They're usually used simply as an alternative based on personal preference, but offer the same benefits as the powder.

There are also collagen supplements in the form of face creams, but it is unclear how truly effective these are.