Collagen is the most abundant protein in your body and makes up connective tissue like skin, muscles, tendons and ligaments.
It provides structure to your skin (which decreases with age), cushions your joints, and strengthens your bones.
There are 28 types of collagen that have been discovered, but there are four common types that each perform a different role in the body, with type 1 making up over 90% of the body. (1)
Four Main Types of Collagen
The four most abundant types of collagen are:
Type 1 (I): this one makes up over 90% of the collagen in the body. It's found in every type of connective tissue.
Type 2 (II): the type in joints and between vertebrae (in the spine).
Type 3 (III): makes up reticular fibers (in the skin and blood vessels).
Type 4 (IV): in the basement membrane zone of the skin and inner ear, kidneys, and eye lens.
Supplements often contain a variety of collagen types, but some only contain one or two. Why Not Natural liquid collagen with biotin only contains type 1 marine collagen, the most abundant type in the body and the most easily absorbed form (marine collagen particles are smaller and easier to assimilate).
Collagen supplements are typically hydrolyzed which means the collagen is broken down for easy absorption.
Benefits of Collagen Consumption
Collagen supplements have become common and have several proven benefits (the amount of benefit will depend on the quality of the supplement). (2)
Collagen can also be obtained from the diet by consuming foods like bone broth. A small amount of collagen comes from eating meat since it is found in the connective tissues.
However, consuming food containing collagen/gelatin may not be as effective as supplementation. Most studies have been performed on the effect of collagen supplements.
There are no vegan or vegetarian sources of collagen, but your body can synthesize collagen. It's important to consume enough vitamin C as it's critical for collagen synthesis.
Skin Health
Your skin loses its elasticity and strength with age because of reduced collagen production over time. Collagen is a large part of the skin structure. It also helps with hydration of the skin.
Supplementation with collagen can help improve the skin's appearance with age, leading to increased moisture and less wrinkles.
Taking 1000 mg per day of collagen has been shown in a randomized, double-blind, controlled study to improve the appearance in as little as 6 weeks. It's thought that oral supplementation stimulates the body's own collagen production, and may improve the production of elastin and fibrillin as well (two other proteins responsible for skin texture). (3)
Another review of 11 studies found that a dose of 3-10 grams of collagen per day showed promising short-term and long-term improvements to skin elasticity, hydration, and density with no adverse effects. (4)
Joint Health
Collagen is found in the cartilage, the cushioning between joints.
With age, the cartilage deteriorates, which increases your risk of degenerative diseases such as osteoarthritis and can lead to pain and stiffness. (5)
Collagen supplementation has been shown in some studies to be an effective treatment and prevention for symptoms of osteoarthritis. (6)
It's been theorized that supplementing collagen orally promotes one's body's own collagen production, leading to lower inflammation, reduced pain, and improved joint support.
A review of 5 placebo-controlled studies including over 500 people concluded that supplementing with 10 grams of collagen per day led to a significant improvement in self-reported joint pain and stiffness. (7)
Bone Loss Prevention
The collagen in your bones gives them strength and structure. With time, both bone density and collagen mass deteriorate, making bones weaker and prone to fractures.
Some studies have shown that supplementing with collagen can reduce this bone breakdown. One 12-month study showed that postmenopausal women who took 5 mg of collagen per day increased their bone mineral density (a marker for bone strength) by 7%. (8)
Low bone mineral density (BMD) leads to an increased risk of osteoporosis and weak bones.
Muscle Mass Improvement
Muscle is another of the body's component that is vulnerable to breakdown with age, as collagen comprises up to 10% of muscle.
Sarcopenia is the name of the condition where muscle mass decreases with age, and a 12-week study showed that the 27 men suffering from this condition who supplemented with collagen gained significantly more muscle mass in a daily exercise program compared with the men who didn't. (9)
It's been hypothesized that supplementing with collagen promotes the body's synthesis of proteins like creatine and stimulates muscle growth after exercise.
Heart Health
The structure of arteries is provided by collagen, and the absence of collagen can lead to arteries becoming inelastic. (10)
Inflexible arteries can lead to atherosclerosis, or narrowing of the arteries. This in turn increases the risk of heart attack and stroke. (11)
A 6-month study where 31 healthy adults supplemented with 16 grams of collagen per day showed a significant improvement in artery flexibility by the end of the study. They also improved their HDL (good cholesterol) levels by 6%, another heart disease risk factor.
Nail and Hair Growth
Many women suffer from brittle and broken nails. A study of 25 participants showed that taking 2.5 grams daily of collagen improved the strength and appearance of nails in 80% of participants after 24 weeks. (12)
It's been hypothesized that the same effect would be shown on hair growth, but there's limited clinical research to support this.
Other benefits
Many practitioners recommend collagen supplementation to improve gut health, brain health, and weight loss. However, at this time there is limited research to support these claims.
Resources
(1) Biochemistry, Collagen Synthesis
Marlyn Wu; Kelly Cronin; Jonathan S. Crane.
https://www.ncbi.nlm.nih.gov/books/NBK507709/
(2) Collagen and gelatin
https://pubmed.ncbi.nlm.nih.gov/25884286/
(3) Oral Intake of Low-Molecular-Weight Collagen Peptide Improves Hydration, Elasticity, and Wrinkling in Human Skin: A Randomized, Double-Blind, Placebo-Controlled Study
Do-Un Kim, Hee-Chul Chung, Jia Choi, Yasuo Sakai, and Boo-Yong Lee
(4) Oral Collagen Supplementation: A Systematic Review of Dermatological Applications
https://www.ncbi.nlm.nih.gov/pmc/articles/PMC6073484/
(5) Cellular aging towards osteoarthritis