Said to make your skin glow, your nails strong and your hair bouncy, there’s little wonder collagen is the beauty buzzword of the moment.

Collagen has become a star ingredient of powders, bars and creams, whose makers promise it will help you reclaim youth, skin elasticity and vigour.

Australian brand Vida Glow, which launched five years ago and is a leader in the ingestible beauty sector, sells a tub of its original unflavoured Marine Collagen powder every four seconds. It’s available in 50 countries online.

Founder Anna Lahey discovered collagen on a holiday in Japan (collagen is commonly used in Japan, added in powder form to drinks and soup). She credits it for fixing her chronic hair loss and weak nails, as well as improving her sleep and reducing sugar cravings.

She says the feedback she gets from customers about her product – which is regulated by Food Standards Australia New Zealand and created in a National Association of Testing Authorities (Nata) certified laboratory in Sydney – particularly from mothers like herself, has been her “pinch me” moment.

“As a mother of two young children [with a third on the way], I delight in reviews from new mothers who have experienced post-partum depletion that directly affected the quality of their hair, skin and nails. I love reading their reviews on our supplements bringing lustre back to their hair or noticing a decrease in hair loss,” she says.

So what is collagen and can you really drink yourself gorgeous?

The 101 on collagen

Collagen is the most plentiful protein in the body. Dietitian Alex Parker, from Sydney-based nutrition consulting business The Biting Truth, says collagen acts like a “glue”, forming the connective tissue in the body between skin and bones, tendons and muscles, and so on.

About 80 per cent of our skin is collagen and, along with another protein called elastin, it keeps skin elastic. Each year the body makes new collagen but, from about your mid-20s onwards, production of it starts slowing down.

As Carla Oates, founder of supplement company The Beauty Chef, points out, this slowing in the production of collagen leads to drier, thinner skin and to wrinkles.

“Anyone who is concerned with premature ageing would benefit from taking a collagen-boosting supplement. Our bodies naturally produce collagen by combining amino acids from protein-rich foods we eat with essential vitamins and minerals such as vitamin C, copper, and zinc.

“[A]s we get older, our production of collagen becomes less efficient, resulting in some of the most common signs of ageing like wrinkles, joint pain and weakened muscles.

“Other lifestyle factors – think UV exposure, high sugar intake, smoking and a diet that’s lacking in nutrients – can also impact both collagen production and the breakdown of collagen,” she says.

So what is a collagen supplement?

Collagen supplements are commonly made from beef, pork and marine life and are a hydrolysed form of the protein, which the body converts to amino acids and sends off to create more protein, and collagen, where it’s needed.

The tricky thing with supplements is you can’t really control how the body will absorb the collagen. As Parker puts it: “Collagen doesn’t absorb in whole form, it breaks into individual amino acids. If you’re having supplements you can’t choose what they become in the body.”

Supplements often come in powder form, which you can add to a drink, as well as snacks such as Krumbled Foods collagen Beauty Bites.

Do beauty ingestibles work?

Given its reported benefits and the world’s obsession with a quick and miraculous fix, there’s been a lot of hype around collagen supplements.

While studies in journals of record such as the Journal of Agriculture and Food Chemistry, the Journal of Cosmetic Dermatology and the Journal of Drugs in Dermatology have found beneficial effects from using collagen supplements, including reducing wrinkles and improving brittle nails, the studies have often been small and research is in its early days.

Dermatologist Dr Adam Sheridan warns there are “no definitive large long-term scientific studies to prove” collagen supplements really do work.

However, he does note that “there is evidence to suggest that a balanced healthy diet, including quality proteins (i.e. proline and glycine), essential vitamins (especially vitamin C, which plays a role in collagen synthesis), minerals and adequate calories contributes to maintenance of healthy skin, muscles and joints.”

Parker is more in favour of a “food first” approach, and says if your diet has adequate protein from components such as meat, eggs, fish and plant proteins such as legumes, there is little need for collagen supplements.

“I’m not denying our body needs collagen, but if you’re getting enough protein you’re going to be getting plenty of amino acids already,” Parker says. “If it sounds too good to be true, it’s likely it is.”

Are there any downsides to taking collagen supplements?

It’s unlikely there is any harm in trying a collagen supplement (other than cost), as there haven’t been any reported side effects. However, studies have so far only been short-term, and Sheridan warns of concerns raised about risk of contamination or unsafe mineral levels in collagen supplements derived from fish or animals.