Collagen

Studies in people

• Benefit

  Skin aging³

  In people, taking hydrolyzed collagen by mouth for 90 days reduced wrinkles and improved skin hydration and elasticity.

• Benefit

  Joint pain and recovery⁴

  In studies of active people, collagen peptides taken with exercise eased joint pain and helped knees and ankles work better.

• Benefit

  Skin and joint health⁵

  Collagen supplements may improve skin elasticity and hydration, and ease joint stiffness and pain.

• Benefit

  Eye wrinkles in women⁶

  In women aged 45 to 65, collagen peptides reduced eye wrinkle volume after 8 weeks.

• Benefit

  Injury prevention in athletes⁷

  In people, taking gelatin before exercise doubled a blood marker of collagen building, which may help prevent injuries.

• Benefit

  Skin hydration and wrinkles⁸

  In women aged 40 to 60, taking collagen peptides daily improved skin hydration, wrinkles and elasticity.

• Benefit

  Knee joint pain⁹

  In people with knee arthritis, daily undenatured type II collagen improved knee symptoms after 180 days compared with placebo.

• Benefit

  Bone strength in older women¹⁰

  In women past menopause, taking collagen daily for a year increased bone density in the spine and hip.

• Open question

  Muscle building in older men¹¹

  In older men, collagen taken with meals did not boost muscle protein building, unlike whey or pea protein.

• Benefit

  Muscle and tendon health¹²

  In adults who trained, daily collagen peptides slightly improved muscle size, strength and tendon appearance, but scientists are not fully sure.

• Benefit

  Skin moisture and elasticity¹³

  In people, hydrolyzed collagen taken for 12 weeks improved skin moisture and elasticity compared with a placebo.

• Open question

  Skin ageing¹⁴

  Scientists do not yet know whether taking collagen by mouth really reduces wrinkles or plumps skin.

• Benefit

  Knee arthritis relief¹⁵

  In people with knee arthritis, undenatured type II collagen reduced pain and swelling short-term, but studies were small and short.

• Benefit

  Skin aging and sleep¹⁶

  Collagen supplements improved skin elasticity and hydration in studies, and good sleep may help them work better.

• Benefit

  Skin elasticity in women¹⁷

  In women aged 35 to 55, a specific collagen taken daily for 8 weeks improved skin elasticity compared with placebo.

• Benefit

  Skin hydration and aging¹⁸

  In people, taking collagen peptides by mouth raised skin moisture and collagen density after several weeks.

• Benefit

  Skin wrinkles and elasticity¹⁹

  In people, taking collagen peptides improved skin wrinkles, hydration and elasticity after 12 weeks.

• Benefit

  Hair loss treatment results²⁰

  In people with hair loss, a supplement with hydrolysed fish collagen plus other nutrients improved treatment results more than treatment alone.

• Benefit

  Skin aging and wrinkles²¹

  In a study of 70 adults, taking collagen peptides daily for 8 weeks improved wrinkles, hydration, and skin elasticity.

• Open question

  Muscle growth with exercise²²

  In people doing 10 weeks of strength training, the collagen group's type II muscle fibers grew less than the supplement group's.

• Open question

  Bone healing after hip surgery²⁴

  In older adults after hip replacement, daily collagen did not change bone turnover markers, though rest pain dropped more.

• Benefit

  Skin and nail aging²⁵

  In East Asian women aged 43 to 65, daily collagen peptides improved skin moisture and dermis density after 84 days.

• Benefit

  Skin elasticity and hydration²⁷

  In a 12-week study, people who took collagen daily had better skin elasticity and less roughness.

• Benefit

  Skin moisture and dryness²⁸

  People who took collagen peptides for 12 weeks had more skin moisture and less roughness than those who did not.

Animal and lab studies only

• Open question

  Cell effects after eating³⁰

  In lab studies, collagen may affect cells after it is eaten, beyond just providing protein.

• Open question

  Skin cell growth³¹

  In lab and animal studies, hydrolyzed collagen at certain amounts stimulated fibroblasts in human and animal tissues without causing toxicity.

• Benefit

  Skin wrinkles and moisture³²

  In animal and lab studies, a collagen peptide powder with plant extracts reduced wrinkles and helped skin hold water.

Study type not stated

• Open question

  Joint health²⁹

  Native and hydrolyzed collagen are the most studied types for joint health, but research links their structure to how they work.

How it’s made and used

• Digested protein in blood²³

  After people ate collagen, small pieces of it showed up in their blood within a couple of hours.

• Appetite after exercise²⁶

  In active women, collagen peptides after cycling led to eating about 41 fewer calories at the next meal.

The signal at the top counts the findings in people and in animal and lab studies. A concern in studies of people outranks animal and lab studies, and “No concerns” needs at least one finding in people. When most findings in people point one way, the page leans that way (“Mostly”), and every finding is still shown. Findings whose study type is not stated are shown but not counted. This page is a reference, not medical advice. It describes what regulators and published research say. Talk to a doctor or dietitian about your own diet.