There’s been a lot of a buzz lately surrounding collagen, and while most of us know it has something to do with our skin, what exactly is it and why should we be incorporating more of it into our diets?
What is collagen?
Collagen is a sticky protein that may as well be thought of as the glue that holds the body together. In fact, the word collagen is actually derived from the Greek word kólla meaning glue. It is the most abundant protein found in the human body, accounting for roughly 1/3 of our total body protein.
To date, 29 types of collagen have been recorded, and of these types, type I, II and III comprise 80-90% of collagen in the body with type I being by far the most abundant (R). Collagen is tremendously important and is found not just in our skin but our tendons, arterial walls ligaments, cartilage, bones, blood vessels, intestinal tract, intervertebral disks, corneas and even teeth!
Collagen protein is made up of three amino acid chained together in a repeating sequence, yielding over 1000 amino acids, every third of which is glycine. Proline and hydroxyproline are also quite abundant. The three strands wind together forming a tightly bound triple helix which is crucial for adding strength to this tissue-forming protein (R) (R).
But don't we make collagen in our bodies?
We tend to categorize amino acids and other nutrients as either essential or non-essential, however some scientists suggest a third category may exist called “conditionally essential” or “semi-essential.” Glycine, the most abundant amino acid in collagen, falls into this conditionally essential amino acid category. Our bodies make it, but not enough for optimal health (choline is another example of a conditionally essential nutrient).
While an average 150 pound human synthesizes about 3 grams of glycine a day, studies over the past 3 decades show that this is not enough for basic metabolic needs. According to a research calculation, we need about 15 grams of glycine per day to account for all our metabolic needs–including the synthesis of collagen (R). This is especially true as we get older. As we age, collagen fibril production in human skin is greatly down-regulated (R).
Collagen plays many impressive roles in the body. Read on to discover some of these functions, as well as some tips for getting more collagen in your diet.
1. Collagen promotes youthful looking skin
Our skin is made up of collagen. As we age our bodies produce less collagen fibrins which contribute to loose, sagging skin and wrinkles (R). Additionally, the modern diet is very high in sugar and carbohydrates. This fact may increase our requirements for collagen, as sugar damages collagen. (R)
Although many factors are attributed to how our skin ages, adding collagen into our diet may be essential in promoting that youthful buoyancy and glowing skin. In one small double-blind, placebo-controlled study, women aged 35-55 received 2.5 grams or 5 grams of collagen daily for 8 weeks. At the end of the 8 week trial, both groups displayed a significant improvement in skin elasticity, skin moisture, transepidermal water loss and skin roughness with significantly higher skin elasticity observed in only 4 weeks (R)!
In another double-blind, placebo-controlled trial with women aged 45-65, subjects were administered 2.5 grams of collagen per day for 8 weeks. After only 4 weeks there was a statistically significant reduction in eye wrinkle volume, while after 8 weeks a statistically significant higher concentration of procollagen type I and elastin was detected. Excitingly, positive long lasting effects were observed 4 weeks after the trial (R). Collagen supplementation has also been shown to reduce skin cracks and improve serum collagen (R).
The literature really does speak for itself here. Healthy skin can be a marker of health and vitally, and, collagen very well may be a piece of that fountain of youth we so much desire.
2. It can improve joint health and prevent degradation
Collagen has been shown to significantly improve joint health. Whether you are suffering from joint pain as an athlete, feeling stiff or are suffering from a disease impacting the joints, collagen may be a key player in your treatment plan.
In a randomized, placebo-controlled, double-blind study conducted at Penn State University, varsity athletes were given 10 grams of type II collagen hydrolysate or a placebo liquid containing xanthan for 24 weeks. At the end of trial period, statistically significant improvements in joint pain at rest, observed by a doctor and self-reported joint pain when walking, joint pain at rest, joint pain when carrying objects and joint pain when lifting was observed (R).
In another randomized controlled trial, subjects diagnosed with knee osteoarthritis were given acetaminophen alone or in combination with 10mg of type II collagen a day for 3 months. At the end of the 3 month intervention, subjects taking the collagen showed significant improvements in joint pain, function and quality of life compared to the baseline levels while the pain relieving group showed only marginal improvements in joint pain and quality of life. The study revealed the group taking the type II collagen experienced a significant improvement in joint pain compared to the group taking only the pain relieving medications (R).
Type II collagen supplementation has also been shown to improve symptoms of rheumatoid arthritis, an inflammatory autoimmune disease of synovial tissue. In one trial 4 of the participants even experienced complete remission of symptoms after 3 months (R).
3. It can improve digestion and reduce inflammation
The role collagen can play in your digestive health cannot be understated. Glycine, the most abundant amino acid in collagen, is a well-documented cytoprotective amino acid and has been shown to be anti-inflammatory, protect gastric mucosa and enhance enterocyte (intestinal lining cells) function (R). A healthy mucosal lining is essential for the production of gastric juices (including hydrochloric acid) and maintaining digestive enzyme balances.
Our intestines are composed of an epithelial lining of cells bound closely together called “tight junctions” that serve as a barrier to keep out invaders such as toxins, allergens and pathogens. The disruption of this gut barrier can be detrimental to your health and is strongly correlated with autoimmune diseases such as inflammatory bowel disease (IBD), celiac disease and infectious colitis to name a few (R). Glycine is anti-inflammatory and has also been suggested as protective agent in the management of IBD (R).
Tumor necrosis factor-α (TNFα) is a proinflammatory cytokine that regulates the function and structure of tight junctions. It has been shown that collagen consumption may protect against TNFα-induced dysfunction in tight junctions (R).
4. It can potentially increase your lifespan
It’s highly unlikely we have evolved eating only the muscle meat of animals, which is what is customary in cuisine today. While all properly-raised meat is nutritious when part of a plant-rich diet, we may be best suited by consuming a more balanced amino acid profile by including collagen, if animal research is any indication.
Muscle meat is high in methionine, an amino acid, which has been correlated with shortened lifespans. Glycine, the most abundant amino acid in collagen, is needed for liver metabolism of excess methionine via the enzyme glycine N-methyltransferase. By eating only muscle meat and skipping glycine-rich portions of the animal such as organ meats, we may be imposing a stress on our bodies that may affect our longevity.
In rats, dietary methionine restriction increased longevity by 30-40%, improved metabolic health, and inhibited tumor growth (R). Because of glycine’s utility in metabolizing excess methionine, researchers hypothesized that dietary glycine supplementation would produce biochemical and endocrine changes similar to the methionine restricted diet findings. What was found is nothing short of astonishing. Rats were fed a controlled diet of 0.43% methionine and 2.3% glycine while the experimental groups got either 4%, 8% or 12% glycine. The median lifespan in the groups fed an 8% and 12% glycine diet increased from 88 weeks to 113 weeks (R)! That’s a 22% increase in lifespan! In the 12% glycine fed group, reductions in mean fasting glucose, insulin, insulin-like growth factor 1 and triglycerides were also observed (R).
In English, what these studies suggest is that a high degree of muscle meat consumption, in a low glycine environment, is not good for us. While human studies are limited, one observational study found that red meat consumption was strongly correlated to type 2 diabetes. However, after controlling for excessive iron, altered blood lipids (which could be the result of a high sugar diet), and low glycine, the correlation between high red meat intake and type 2 diabetes was largely negated (R).
5. It can increase muscle mass
This one may come as a bit of a shock because it is certainly not what conventional muscle building wisdom would have us believe. However, it is very true nonetheless. In a randomized double blind, placebo controlled study, a group of elderly men participated in a 12 week resistance training program. After the 12 week period, it was found that the group supplementing with 15 grams of collagen per day showed statistically significant higher levels of fat-free mass, bone mass, isokinetic quadricep strength, and sensory motor control while exhibiting statistically significant lower levels of fat mass when compared to the placebo group (R).
6. It can improve mood, cognition and sleep
Glycine is an inhibitory neurotransmitter in the central nervous system. In fact roughly half of the inhibitory synapses along the spinal cord utilize glycine while most of the other inhibitory synapses use GABA. Glycine as an inhibitory neurotransmitter can induce feelings of calmness reducing anxiety and boost mental clarity (R). Glycine ingestion has also been shown to improve sleep and improve daytime sleepiness and fatigue caused by sleep restriction (R) (R).
7. It can improve wound healing
Collagen originally earned its name (from the Greek word kólla meaning glue) when it was observed that gelatin, a glue-like substance, was derived after boiling animal hide (R). This stickiness is critical during wound healing, when we need increased collagen to essentially “glue” wounds back together. It has been shown that increasing collagen intake in patients recovering from pressure ulcers sped up healing time at nearly twice the rate compared to a control group (R). Collagen-based wound dressings have long been used to cover wounds and continue to be used as dressings for ulcers on patients to speed recovery time (R) (R).
Foods that support your body's synthesis of collagen
1. Eat all the bits and clean your bones!
If you’re eating meat don’t just eat the lean muscle. Like our skin, the skin of animals is rich in collagen. So don’t fret about the low fat “remove the skin” fad we’ve experienced the past couple decades; now you can eat the skin and reap the benefits. Other parts of animals that are high in collagen include; cartilage, shanks, necks, feet, cheeks, oxtails and ribs. Lastly, make sure you clean the bones! The meat on the bones closest to the joint is a fantastic source of collagen! To that end, check out my ultra-healthy recipe for Insanely Crispy Gluten-Free Buffalo Chicken Wings which are rich in collagen.
2. Eat gelatin
Often times we hear collagen and gelatin used interchangeably. Gelatin is hydrolyzed collagen usually made from bovine bones in a process that breaks the collagen bonds and leaves individual intact amino acids. This solution of amino acids forms a jelly-like substance (this is gelatin) and when ingested can be used as building blocks by your body to form new collagen. A benefit of using gelatin is that for most people it is easily digestible as the protein is already broken down into free form amino acids. Additionally, gelatin is quite easy to cook with and can be purchased as a powder. Gelatin makes a delicious addition to sauces and can even be turned into a homemade sugar-free Jello-like dessert! (R)
3. Drink bone broth
After you eat all the parts of the animal you can boil the bones to extract the collagen. This process is lengthy as you will want to slow cook the bones for about 24-48 hours (depending on the type of bones). What I do is place the bones in a crock pot, add water, some apple cider vinegar and slow cook the bones for 24 hours. You will notice when you remove the bones they will look quite brittle. When the broth cools to room temperature the broth should form a jelly-like substance which as described above is the hydrolyzed collagen forming gelatin. Bone broth is not new but its buzz is picking up steam as people learn the many benefits it elicits.
Note: Bones are a storage site in the body for many minerals and heavy metals–including ones like lead that we do not want to ingest. When making your own bone broth, make sure the bones are sourced from somewhere you know and trust with high quality animal feed standards (R).
4. Take a hydrolyzed collagen powder
If you’re not into eating copious amounts of skin, gelatin or boiling bones, you can purchase hydrolyzed collagen as a supplement. Hydrolyzed means the collagen protein has been broken down into single amino acids. It’s important to get a brand that states the source and isn’t simply mixing glycine, proline and hydroxyproline in some concoction. If you’re looking to improve skin, look for a product with a high percentage of type I collagen mixed with type III. If you want a collagen to promote joint health, look for one with type II collagen.
As of this writing, I use Bulletproof collagen protein (no formal affiliation with the company) which comes from pasture-raised cows. It has very little flavor and so I mix it into coffee, smoothies, tea, or just an 8oz glass of water.
5. Increase your vitamin C intake
That’s right! Foods high in vitamin C can help in the formation of collagen. Hydroxyproline is an amino acid found in high concentration in collagen. Hydroxyproline is made by modifying proline amino acids after the collagen chain has already been built! This process depends on vitamin C as a cofactor for the reaction to occur. Vitamin C is so essential in this process that without it the construction of new collagen would not occur - this is ultimately the deficit causing the disease known as scurvy (R). Foods high in vitamin C include; oranges, kale, red peppers, brussel sprouts, broccoli, green peppers, strawberries and so many more! Think colorful fruits and vegetables. Load up especially on the vegetables as vitamin C concentration is by no means the only benefits you’ll be reaping!
If I have not convinced you to add more collagen into your diet after this post, I don’t know what will! The science is compelling and I highly encourage you to experiment with getting more collagen protein. Let me know your favorite way to incorporate collagen into your diet in the comments below!
Written with contributor Katie Bigras