In a society of abundance, we can afford to keep only one part of the animal, its muscle, discarding everything else.

Our ancestors could not afford this luxury. In nature nothing is wasted. And many of the things we consider “waste” today are actually health treasures.

I have already spoken of the importance of including other parts of the animal in the diet. Today we delve into a specific one, collagen, also known as the youth protein. It will be for something.

Collagen and gelatin

Collagen is the most abundant protein in mammals (including humans). It is the most important component of the skin, bones and connective tissues. It represents almost a third of our total protein mass.

Too used to represent a relevant part of our diet. No longer.

Since collagen appears in poorly digestible areas, our ancestors cooked them to extract their precious nutrients.

And so we discovered the jelly. Basically cooked collagen.

The amino acids that form it (glycine, proline and lysine) are non-essential, that is, the body can synthesize them from others, and then use them to produce its own collagen.

But that the body can manufacture them does not mean that it does not benefit from an additional contribution in the diet, for several reasons:

  • The body is unable to produce enough glycine for daily collagen synthesis. This study for example calls this deficiency «a weak link in metabolism«. I don’t think it’s any Weak link, but a simple reflection of the importance that collagen had in our diet, hence our poor ability to produce it.
  • The wisteria is really considered a conditionally essential amino acid. That is to say, in certain situations (such as illness or injury) our synthesis capacity is even more limited, making this amino acid essential (detail). Better to include it in the diet.
  • Collagen synthesis decreases with age (study, study). As we age, it is more important to ensure that we supply the body with enough raw material to sustain production. In women, the drop in estrogen at menopause also reduces collagen synthesis (study).


It’s not called the protein of youth for nothing. Let’s see what the studies tell us.

Good for joints, tendons and muscles

  • Reduces joint pain, both in athletes (study) and in older people (study). In both studies about 10 grams of collagen are used per day, the estimated amount that an adult of about 70 kg requires, and higher than that synthesized by our body (study).
  • A diet rich in glycine strengthens the Achilles tendon (study in rats), one of the weak points of many athletes. We also have evidence in humans (study, study).
  • May improve symptoms of arthritis, according to this review. This other study concludes that the evidence is still small, but since cartilage is 2/3 collagen, it is not unreasonable to try.
  • Helps to gain muscle. Although its role in muscle development has not been considered relevant, a recent study nevertheless shows greater gains in older people (> 65 years) who supplemented with collagen after training. And without a doubt more muscle makes you look younger. The comparison with the classic whey protein would be interesting, but at least we know that collagen also helps.

In this article I delve into collagen for joint health.

Rejuvenates the skin

Botox is in fashion. It works by paralyzing small facial muscles. If the muscles do not contract, the lines of expression are not seen. But wrinkles are not caused by muscle contractions, but by the loss of collagen (study).

The skin is the largest organ in the human body, and collagen is its main component.

skin collagen

Multiple studies show that frequent collagen consumption reduces wrinkles and signs of aging (meta-analysis, review, study, study, study, study, study).

A study in mice also shows a protective effect against solar radiation, and this in humans indicates that it helps in recovery after sun damage.

Improves amino acid balance

Abusing skeletal muscle as a protein source can lead to a methionine surplus, contributing to the elevation of homocysteine ​​levels, one of the factors related to cardiovascular disease (study).

Glycine in collagen helps convert homocysteine ​​into glutathione, a powerful antioxidant that reduces the aging of our body (study), and its anabolic role has recently been demonstrated (study).

In short, eating the whole animal produces a better balance of amino acids than gorging on steaks and chicken breasts.

Help to rest

Glycine acts as inhibitory neurotransmitter, like GABA and serotonin. Therefore, it favors relaxation and activation of our parasympathetic system (study).

Many know from experience that a bone broth at night helps you sleep better. Today science proves it. A few grams of wisteria improves sleep quality and reduces fatigue (study, study, study).

Ideas to eat more collagen

There are two ways to increase your collagen intake: food and supplements. My recommendation is always to prioritize real food, but in specific cases supplements are justified. Let’s see both.

Real food

To eat more collagen, we must recover traditions in danger of extinction. Any ideas:

  • Eat skin. I know that years of anti-fat dogma will make you question this recommendation, but the skin is an excellent supply of collagen and healthy fats (not scorched and ideally not fried).
  • Eat traditional dishes: Pork trotters, tripe, stewed tongue …
  • Fish broths and bone broths, in slow cooker or fast cooker. Without a doubt my favorite sources.
  • Gelatin desserts. Be careful when buying the gelatin, it must be pure, without flavor or sugar. You will find several recipes in The Revolutionary Plan.


Like a piece of steak doesn’t go straight to your muscle, gelatin doesn’t magically turn into skin and cartilage. Like any protein, collagen breaks down into its amino acids when digested. These amino acids will later be used by the body to build the structures it needs.

That is, there are no guarantees that the ingested collagen will end up where you want it (the forehead wrinkle?), But the synthesis of new collagen is more likely to work well if you give it the right building blocks (amino acids) (study).

It’s the same with supplements, but they have an advantage. Hydrolyzed collagen is much more assimilable, facilitating its arrival in bones and cartilage (study, study, study, review, study, study).


Although I recommend prioritizing natural collagen (also for the price), many situations may make it advisable to add a supplement to maximize absorption, especially if you suffer from joint pain, you are recovering from an injury, ulcer (study, study) etc. In these cases a daily dose of 8-10 grams of hydrolyzed collagen can help. More detail.

Protect the collagen you have

It is not only about synthesizing new collagen, it is also about avoid losing the one you have. Protect yourself from their great enemies:

  • Inactivity. The best thing for your bones and joints is exercise. No supplement comes close to the power of physical activity, especially strength training performed with good technique and full ranges of motion. In order for your body to add more collagen to bones, tendons, and joints, you need to let it know that you need it, and strength is the way.
  • Industrial food. Sugar damages proteins through a process called glycation (elevated in diabetics), accelerating aging and the breakdown of collagen (detail).
  • Tobacco. It is no secret that smoking is bad. One of its effects is the loss of collagen and premature aging of the skin (study). The same could be said of excess alcohol.
  • Stress and little rest. Chronic stress damages collagen and reduces its synthesis (study), as does lack of sleep (study). Melatonin has a protective role for the skin (study).
  • Incorrect sun exposure. The sun is a double-edged sword. On the one hand, it is the best source of vitamin D, essential for bone and skin health. On the other hand, UV rays can damage collagen in the skin (study). The key is to take the proper dose gradually, avoiding the current approach, where we go from spending all day in the office to lying on the beach for hours on vacation. Your skin is not ready for this.

In short, if you want to look and move like someone younger, eat more collagen and avoid losing what you have.