Are the promises of beautiful hair & skin, increased bone strength, etc. backed by science and common sense?
Some are beneficial, many are scam. This is my second post on food supplements.
Food Supplements #1: Should you take DHA during pregnancy?
one of the top-selling food supplements on Amazon. img Source
The beauty and fitness industry have found another common friend: collagen supplements. From a quick check on Amazon’s bestsellers in the category “Vitamins & Dietary Supplements”, the ranks 3 & 4 are taken by such products, which claim to:
- promote healthy, youthful skin
- promote “healthier hair”
- “keep bones healthy and strong”
- help to keep weight
- stronger tendons, cartilages, joints,…
And they are even gluten free!!! What an incredible surprise for a compound extracted from cattle. (Not.)
Sorry, I’m losing my professional distance already.
The thing sure sounds great! But are these claims backed by science? What is collagen, anyway? Read on…
What is collagen?
Collagen is a structural protein produced by animals – and animals only - including humans. It generates the firm structure of connective tissues, is an elementary component of hair, ligaments, joints and bones and also plays an important role in muscle tissue.
And indeed, the more collagen your body is able to produce, the stronger your bones, the firmer your ligaments, the smoother your hair and skin will be. When we grow old, our body synthesizes less and less collagen, and we get cartilage erosion, weaker bones, but also wrinkles and bad hair – we know this kind shit from a morning ritual that is including a look into the mirror.
So in theory, if you would take up more collagen from the exterior, this should really lead to what the supplement suppliers claim.
Does it work, then?
Some science says yes…
There are a few, mostly industry-paid, studies that support the health benefits of collagen supplements – in particular for the skin (quoted at the bottom of this post). Those compared a group of persons that got collagen for some time with others that did not and found it to work, at least to some extent.
Wait, don’t switch to Amazon yet, youth nostalgics! Let’s apply common sense and read again to what I wrote above: Collagen is a structural PROTEIN. If you eat a protein, is it just transferred to your blood circulation and able to reach skin, bones and hair?
The answer is NO. Our enzymes of the gastrointestinal tract treat collagen just as any other protein they see. They cut it to small pieces.
So after the digestion, all that is left from your collagen powder are the basic building blocks of any protein: amino acids.
Which are great. They are valuable nutrients that are taken up and our body produces new proteins with them. But it makes little difference whether you ate a steak, some eggs or drank a milky solution of collagen… in the end, your digestion cuts it all to pieces, and no single collagen macromolecule will ever reach your skin or any other part of your body.
So it's hard to immagine that collagen is responsible for the claimed effects.
But what about the science???
Ah, the studies. The studies I quoted have a significant flaw:
They used a placebo (a similar-tasting sauce without collagen) that did not contain other proteins. So in the end, test persons who got the real supplement ended up with digesting a lot more proteins, and thus took up much more amino acids, an abundance that motivates the body to produce more own proteins, including – yes – human collagen.
The same effects would probably have been observed by feeding people a grilled chicken breast. Which might be the reason why those studies were published in quite low / lower middle-class - rated journals.
My "supplement", probably at least as healthy as the one shown at the top. img source
But nobody tested it – why?
Sad but true: Because nobody paid for it. No halfway sane researcher would conduct a long, exhausting and especially expensive (human trials ARE expensive) study just to observe…no effect.
Unless you get paid to do it, of course. And obviously, chicken farmers never had the idea to pay for a study proofing their product to be as good for skin, hair and ligaments as a popular food supplement.
While eating collagen might improve your skin, hair, ligaments, bones and cartilages, common sense says: So could any other surplus of proteins.
I personally think collagen supplements are useless, and I am not alone with that. Most nutrional scientists and medical doctors agree that nutritional collagen wouldn't reach your skin or any other proclaimed target.
Should a properly conducted and independent study prove me wrong, I will apologize. But until then, I’m sticking with chicken breast.
Disclaimer: In my blog, I'm stating my honest opinion as a researcher, not less and not more. Sometimes I make errors. Discuss and disagree with me - if you are bringing the better arguments, I might rethink.