You might recognize it as an ingredient in your favorite body lotion or perhaps noticed supplements in the vitamin aisle that feature it. But what is collagen, exactly ­­— and how can you incorporate it into your life?

Collagen is the most abundant protein in your body. It’s found in muscles, bones, skin, blood vessels, digestive system and tendons. It’s what helps give our skin strength and elasticity, along with replacing dead skin cells. When it comes to our joints and tendons, in simplest terms, it’s the “glue” that helps hold the body together.

Our body’s collagen production naturally begins to slow down as we age. We can thank this degenerative process for signs of aging, such as wrinkles, sagging skin and joint pains due to weaker or decreased cartilage (hello, skeleton legs). Other lifestyle factors — like eating a diet high in sugar, smoking and high amounts of sun exposure — also contribute to depleting collagen levels. It’s been found that collagen-related diseases most commonly arise from a combination of either genetic defects, poor intake of collagen-rich foods, nutritional deficiencies and digestive problems affecting production (synthesis) of collagen.

Thankfully, consuming a little known but yummy food can provide plenty of this vital protein, and if you’re wondering what is collagen good for, I’m glad you asked.

As we age, collagen production declines — it’s happening as you read this! You’ll notice it physically: looser skin, more wrinkles and less elasticity. Increasing collagen levels can help your skin look firmer, increase smoothness, and help your skin cells keep renewing and repairing normally.

Double-blind, placebo-controlled studies investigating the anti-aging properties of collagen have found that 2.5–5 grams of collagen used among women aged 35–55 once daily for eight weeks significantly improved skin elasticity, skin moisture, transepidermal water loss (dryness) and skin roughness, all with little to no side effects. This makes collagen one of the best natural skin care ingredients available.

Collagen also reduces cellulite and stretch marks. When skin loses its elasticity as a result of decreased collagen, there’s another side effect: more visible cellulite. Because your skin is now thinner, cellulite becomes more evident — no more hiding what’s happening below the surface. Improving your skin’s elasticity through collagen helps reduce that dimpling on your skin.

Have you ever felt like you’ve got “skeleton legs,” the types that feel extra stiff and cause pain when you move? Yup, that’s likely a loss of collagen rearing its ugly head. That’s because when we lose collagen, our tendons and ligaments start moving with less ease, leading to stiffness, swollen joints and more.

With its gel-like, smooth structure that covers and holds our bones together, collagen allows us to glide and move without pain. Think of ingesting more collagen like greasing a creaky door hinge: It helps your joints move more easily, reduces pain often associated with aging and even reduces the risk of joint deterioration. It’s no surprise then that a recent study even found that collagen is an effective treatment for treating osteoarthritis and other joint pain and disorders.

Researchers at Harvard’s Beth Israel Deaconess Medical Center in Boston found that supplementing with type 2 collagen helped patients suffering from rheumatoid arthritis find relief from painful symptoms by decreasing swelling in tender joints. Another study published in the International Journal of Medical Sciences found that people with osteoarthritis joint pain treated with type 2 collagen show significant enhancements in daily activities, such as walking up stairs, ascending or sleeping, and a general improvement in their quality of life. 

If you suffer from leaky gut syndrome, a condition where bad-for-you toxins are able to pass through your digestive tract, collagen can be super-helpful. It helps break down proteins and soothes your gut’s lining, healing damaged cell walls and infusing it with healing amino acids.

The biggest digestive benefit of consuming more collagen is that it helps form connective tissue and therefore “seals and heals” the protective lining of the gastrointestinal tract. Today, we know that many illnesses can actually be traced back to inflammation or irritation stemming from an unhealthy gut. Poor gut health — including changes in the gut microbiome and permeability in the gut lining — allows particles to pass into the bloodstream where they can kick off an inflammatory cascade (hence the name leaky gut syndrome).

Studies have found that in patients with inflammatory bowel disease, serum concentrations of collagen are decreased.  Because the amino acids in collagen build the tissue that lines the colon and GI tract, supplementing with collagen can help treat gastrointestinal symptoms and disorders, including leaky gut syndrome, IBS, acid reflux, Crohn’s disease and ulcerative colitis. In addition to helping heal leaky gut, collagen also helps with the absorption of water within the intestines, keeping things moving more freely out of body.

A boost in collagen may help increase your metabolism by adding lean muscle mass to your frame and helping with the conversion of essential nutrients. One of glycine’s most important roles is helping form muscle tissue by converting glucose into energy that feeds muscle cells. And remember that retaining muscle mass is crucial as you age, since it helps support posture, bone health and burns more calories than fat. When consuming collagen, you can benefit from also consuming vitamin C to ensure your body can convert the collagen into a useable protein. This can begin to restore the source or your energy and vitality.

That’s not all that glycine can do for your metabolism. Research shows glycine also has important roles in both functions of the digestive and central nervous systems, which play big roles in maintaining a healthy, youthful body.  Glycine seems to help slow the effects of aging by improving the body’s use of antioxidants and is also used in the process of constructing healthy cells from DNA and RNA.

Ever had peeling and splitting nails? Well, a lack of collagen could be to blame. Collagen protein is the building block of your fingernails, hair and teeth. Adding collagen into your diet regimen can help keep your nails strong and possibly reverse signs of hair loss.

A study published in the Journal of Investigative Dermatology found that there’s an “essential relationships between extracellular matrix (ECM) and hair follicle regeneration, suggesting that collagen could be a potential therapeutic target for hair loss and other skin-related diseases.”

If you’re looking to detox your body of harmful substances, improve blood flow and keep your heart young, collagen is extremely helpful. That’s because glycine helps minimize damage your liver experiences when it absorbs foreign substances, toxins or alcohol that shouldn’t be passing through it.

The amino acid proline helps your artery walls release fat buildup in the bloodstream, shrinking the fat in the arteries and minimizing fat accumulation. Proline is needed for tissue repair within the joints and arteries, plus it helps control blood pressure. As part of collagen found within joints, it buffers our bodies from the effects of vibration or shock and helps us hold on to valuable cartilage as we get older.   It’s also linked with the prevention of arteriosclerosis (hardening of the arteries) since it helps our arteries stay clear of dangerous plaque buildup.

In addition, arginine helps with nitric oxide production, which allows for better vasodilation — meaning the widening of arteries and relaxation of muscle cells and blood vessels that allows for better circulation.