DEAR MAYO CLINIC: I’ve read that collagen and biotin are good for the body. What are these supplements and are they beneficial?

ANSWER: Collagen and biotin supplements are promoted for healthy aging, along with joint and bone health. However, it is important to understand what collagen and biotin are and what research is available to support these claims.

Collagen is concentrated in bones, ligaments, tendons, skin, blood vessels and internal organs. It helps provide elasticity and strength. As you age, you begin to lose the collagen within your body, and it becomes harder for you to make more.

At least 30% of your body’s protein content is made from collagen. Collagen is made from amino acids, which are the building blocks for protein: always glycine, often with proline and hydroxyproline. These amino acids are grouped together into collagen’s characteristic triple helix. For this triple helix to be formed, you need to have enough vitamin C, zinc, copper and manganese in your body.

Within the human body, more than 20 types of collagen have been identified, with three types making up the vast majority.

These are the types you’ll usually find in a collagen supplement:

• Type I
  This type is found in bones, ligaments, tendons and skin for elasticity and strength. The supplement comes from cows (bovine) and fish.
• Type II
  This type is cartilage. The supplement comes from chickens.
• Type III
  This type is found alongside type I in skin, blood vessels and internal organs. The supplement comes from cows.

If you are planning to take a collagen supplement, either in liquid or powder form, it is important to mention that the triple helix that makes up collagen is unable to be absorbed in its whole form. It will first be broken down into individual amino acids within the gastrointestinal tract before reaching the bloodstream. The body will then reassemble and form new proteins where necessary and use as needed.

These new proteins may not contain the same amino acids that were initially ingested in the collagen supplement, and it is unknown if these restructured proteins will target the area a supplement manufacturer is advertising. Therefore, it is undetermined if the body will use a collagen supplement that is purported to help skin, hair, nails and joints to actually make collagen that would do so. In addition, limited large and long-term randomized controlled trials support the use and recommendation for collagen supplements.

From a general health perspective, it is important to ensure adequate protein within your diet. As you age, your protein needs increase slightly to maintain lean body mass. Consuming foods that contain the primary amino acids that make up collagen may help support skin, hair, nail and joint health as you age.

These foods are good sources of amino acids commonly found in collagen:

• Bone broth.
• Unflavored gelatin.
• Dairy, especially parmesan cheese.
• Legumes.
• Non-genetically modified soy, such as tofu.
• Spirulina.
• Animal sources, such as red meat, poultry, pork, fish and eggs.

To support the formation of collagen, it is also important to ensure adequate intake of foods that contain vitamin C, zinc, copper and manganese. These nutrients can be found by eating a varied diet rich in fruits and vegetables, including green leafy and root vegetables, along with nuts and seeds — especially hemp, pumpkin and cashews.

Finally, being mindful of what can damage collagen production is important. Such factors include excess sugar intake, smoking, sun exposure or ultraviolet light, and environmental pollutants.

Biotin is a form of the vitamin B7 that helps enzymes break down fats, carbohydrates and protein. While it has been marketed for healthier hair, skin and nails, there is limited evidence that taking additional biotin will achieve these outcomes.

Taking biotin in supplement form may only benefit those with an underlying medical condition that interferes with biotin absorption or those who are deficient, such as people with alcoholism. For the general population, adequate biotin intake of 30 micrograms per day can be achieved from diet alone without supplements. Biotin can be found in salmon, avocado, sweet potato, pork, nuts and seeds.

High doses of biotin — 10 to 300 milligrams per day — can provide false high or low blood levels of thyroid-stimulating hormone, vitamin D and troponin. Therefore, it is important to let your health care provider know if you are taking a biotin supplement — or any supplement.