A guide to collagen supplements

Collagen is growing in popularity as a supplement with all sorts of accompanying claims. Dietitian Katrina Pace sorts the wheat from the chaff.

What is collagen?

Collagen is the most abundant protein found in our body. It gives elasticity, strength and stability to many tissues, including skin, bone, ligaments and tendons. Collagen supplements are often promoted as beneficial for joint care or hair, nail and skin care.

What’s available?

Supplements tend to use either beef or fish as the source of collagen. Refined collagen capsules are most common, but powdered collagen hydrolysate is becoming more popular. Supplements vary considerably. Collagen powders are generally pure collagen hydrolysate, but the capsules may contain other vitamins, minerals or herbal compounds. Make sure you check the amounts of vitamins and minerals you’re getting in total if you’re taking more than one supplement a day.

Why do people take collagen?

Joint pain, osteoporosis and osteoarthritis

Collagen plays an important role in stabilising joints, providing structure in bones and maintaining elasticity of ligaments and tendons.

A 2016 systematic review, looking at both rodent and human studies, found collagen supplements may be beneficial for improving movement and strength in joints. A daily dose equivalent to 12g collagen hydrolysate powder seemed to help symptoms of osteoporosis and osteoarthritis. In one study, with 200 people aged 50 years and older, six months of taking a supplement containing 1200mg (1.2g) of collagen hydrolysate showed improvement in symptoms of joint pain.

Skin, hair and nails

Collagen gives skin its elasticity and provides the hard structure for nails.

Studies seem to show collagen supplements can improve skin elasticity and hydration. There is no consensus as to how much collagen is needed, but most studies have used 5g-20g collagen hydrolysate daily.

Gut health

Recently, collagen powder has been promoted to help gut health. The link between collagen and digestion is that the gut, as a muscle, needs collagen to remain elastic. Inflammatory bowel diseases (IBD) are characterised by disordered clumping of collagen fibres, and low blood levels of certain types of collagen have been seen in one study in a group of people with IBD.

However, no research has directly linked collagen supplements or powders to an improvement in gut health or digestion.

Side effects

Collagen is quite a safe supplement to take, with no recognised upper limit. Some people report bloating, reflux or indigestion, possibly related to either the high amount of protein in collagen or the ability of collagen to bind with water. If you’re allergic to fish, then avoid a marine-based collagen supplement.

Can’t I just get collagen from food?

Gelatin-containing foods, such as jelly, are high in collagen. Bone broths, where the cartilage is boiled down, also contain collagen.