Collagen-Rich Foods: What to Eat and What Works

Only animal foods with connective tissue contain collagen: gelatin, bone broth, tough cuts of meat and fish skin and bones¹. One tablespoon of plain gelatin (7 g) gives about 6 g of collagen protein², while a cup of bone broth gives 5-10 g, depending on the batch¹.

Your body breaks eaten collagen down and builds its own from amino acids, and it needs vitamin C to do it³. So the most useful "collagen diet" pairs enough protein with fruit and vegetables rich in vitamin C. For what collagen supplements can and can't do, see our evidence page.

Gelatin is the richest everyday source, because it is collagen that has been boiled out of animal bones, cartilage and skin¹. The foods below are the ones that actually contain collagen, from the most concentrated to the least predictable^{2, 1}:

• Unflavoured gelatin, 1 tablespoon (7 g): about 6 g protein and 23 kcal; plain gelatin is 85.6 g protein per 100 g².
• Bone broth, 1 cup: 5-10 g protein, almost all of it from gelatin; bones are simmered for 4 to 24 hours, often with a little vinegar¹.
• Tough cuts of meat: pot roast, brisket and chuck steak are full of connective tissue¹.
• Fish skin and bones: both freshwater and saltwater fish carry collagen in these parts¹.

Eggs, dairy, legumes and soy are not collagen sources, but they supply the amino acids collagen is built from¹. Food tables report protein rather than collagen, so gelatin's protein figure is the most reliable number you can use².

How much collagen is in bone broth?

Less, and less consistently, than people expect. A 2019 analysis of commercial, café and home-made bone broths found that broth made to a standard recipe had significantly lower glycine, proline and hydroxyproline than a 20 g dose of the collagen supplements used in research⁴. Broths made to different recipes varied widely, with café broths highest; made to the same recipe, shop-bought broths were lower than home-made ones⁴. The authors concluded that bone broth is unlikely to be a reliable source of collagen building blocks⁴.

Not as intact collagen. Digestion breaks collagen into amino acids and small fragments, which go wherever the body needs protein¹. Some of those fragments do reach the blood: after people ate 9.4-23 g of gelatin hydrolysate, peptide-bound hydroxyproline peaked at 20-60 nmol/mL of plasma within 1-2 hours, mostly as the dipeptide Pro-Hyp⁵.

Whether those peptides change skin or joints is a separate question, and almost all of the trial evidence comes from supplements rather than food. Harvard's nutrition department notes there is no research showing that eating collagen-rich foods directly benefits skin or joint health¹.

What the supplement trials show

• Skin, positive pooled result: a 2021 meta-analysis of 19 trials in 1,125 people aged 20-70 found better skin hydration, elasticity and wrinkles after about 90 days of hydrolysed collagen⁶.
• Skin, a larger pool: a 2023 meta-analysis of 26 trials in 1,721 people found the same gains in hydration and elasticity, but flagged several biases in the trials⁷.
• Skin, the null result: a 2025 meta-analysis of 23 trials in 1,474 people found no effect in trials without industry funding, and none in the high-quality trials⁸. Its authors concluded there is no clinical evidence that collagen supplements prevent or treat skin ageing⁸.
• Joints: in a 2018 meta-analysis of 69 trials of 20 supplements for osteoarthritis, collagen hydrolysate had a large effect on pain in the short term, and undenatured type II collagen was one of only two supplements with a clinically important effect at medium term⁹. The overall quality of evidence across these trials was very low, and no supplement helped in the long term⁹.
• Side effects: across those osteoarthritis trials, supplements other than diacerein caused no more side effects than placebo⁹, and Harvard's review found no negative side effects reported in collagen trials¹.

The pair pages weigh these trials in more detail: collagen for wrinkles, collagen for skin elasticity and collagen for osteoarthritis.

Is collagen a good source of protein?

Not on its own. Collagen has no tryptophan, an essential amino acid, so it counts as an incomplete protein¹⁰. USDA data for plain gelatin list 0 g of tryptophan². A 2019 modelling study found collagen could still replace up to 36% of the protein in a typical Western diet without falling short on essential amino acids¹⁰.

Foods rich in vitamin C, protein and zinc matter more than collagen itself, because your body makes collagen from them^{1, 3}. Vitamin C is required to build collagen, and a severe shortage causes scurvy, with fatigue, weak connective tissue, fragile capillaries, easy bruising and poor wound healing³.

Best vitamin C foods for collagen

Adults need 90 mg a day (men) or 75 mg (women), 85 mg in pregnancy and 120 mg while breastfeeding; people who smoke need 35 mg more³. These servings come from the NIH vitamin C fact sheet, with the share of the 90 mg Daily Value³:

• Red bell pepper, raw, ½ cup: 95 mg (106% DV)
• Orange juice, ¾ cup: 93 mg (103% DV)
• Orange, 1 medium: 70 mg (78% DV)
• Kiwifruit, 1 medium: 64 mg (71% DV)
• Green bell pepper, raw, ½ cup: 60 mg (67% DV)
• Broccoli, cooked, ½ cup: 51 mg (57% DV)
• Strawberries, sliced, ½ cup: 49 mg (54% DV)
• Brussels sprouts, cooked, ½ cup: 48 mg (53% DV)
• Tomato, raw, 1 medium: 17 mg (19% DV)

In an observational study of 4,025 American women aged 40-74, higher vitamin C intake was linked to lower odds of a wrinkled appearance (odds ratio 0.89) and of age-related skin dryness (odds ratio 0.93)¹¹. That links diet to skin appearance but cannot prove cause. Our vitamin C for collagen production page reviews the trials.

Protein and zinc foods

Collagen is built mainly from glycine, proline and hydroxyproline¹. These foods supply the raw materials¹:

• Amino acids: fish, poultry, meat, eggs, dairy, legumes and soy.
• Zinc: shellfish, legumes, meat, nuts, seeds and whole grains. Our guide to foods high in zinc gives amounts per serving.

Does pairing gelatin with vitamin C help?

Possibly, around exercise. In a crossover trial in 8 healthy men, 15 g of vitamin C-enriched gelatin taken 1 hour before 6 minutes of rope-skipping doubled a blood marker of collagen production¹². A follow-up in 10 recreationally active men found the marker rose about 20% after gelatin or hydrolysed collagen, but the variation was too large for the result to be significant¹³.

Supplements in this guide

• Collagen (Hydrolyzed)
• Vitamin C
• Zinc
• Glycine
• Collagen Type II

No. Collagen in food comes only from animal flesh and connective tissue, and gelatin is made from animal bones, cartilage and skin¹. No fruit or vegetable contains collagen.

Vegetarians and vegans can still give the body what it needs to make collagen^{1, 3}:

• Amino acids: legumes, soy, and for vegetarians eggs and dairy¹.
• Zinc: legumes, nuts, seeds and whole grains¹.
• Vitamin C: a kiwifruit (64 mg) plus ½ cup of strawberries (49 mg) is more than a day's need on its own³.

The "fruits with collagen" in search results are really fruits high in vitamin C, such as citrus, kiwi and berries¹.

Age, sun and smoking are the best-documented causes, with sun exposure the largest environmental factor^{14, 15}. Skin relies mostly on collagen types I and III, and ageing reduces the production of both¹⁶. The evidence for each cause:

• Age: skin cells from people over 80 made about a third less type I procollagen in the lab than cells from people aged 18-29 (56 vs 82 ng/mL)¹⁶.
• Sun: UV light is the main environmental cause of skin ageing, and the damage builds up with exposure and is greater in lighter skin¹⁴.
• Smoking: in 47 smokers compared with 51 people who had never smoked, skin made 18% less type I and 22% less type III collagen¹⁵.
• Other habits: excess alcohol, too little sleep or exercise, and chronic stress are also linked to lower collagen production¹.

Shielding the collagen you have, with sunscreen and by not smoking, is the best-supported step^{1, 14, 15}. Our premature ageing page covers the supplements tested for skin ageing.

Collagen foods are safe for most people, but a few groups should take care with how they get them.

• Heavy bone-broth drinkers: one small study found broth made from chicken bones had three times the lead of broth made from the meat alone, although levels stayed below half the drinking-water limit¹.
• People who smoke: you need 35 mg more vitamin C a day than non-smokers³.
• High-dose vitamin C users: the adult upper limit is 2,000 mg a day, far above what food provides; high doses can cause diarrhoea, nausea and cramps³. People with hereditary hemochromatosis should avoid high-dose vitamin C supplements, because they can worsen iron overload³.
• Supplement users: supplements are not reviewed for safety or effectiveness before sale, and some collagen products have raised concerns about heavy metals¹.

Gelatin is made from animal bones, cartilage and skin, so it does not suit vegetarian or vegan diets¹.

Food covers what your body needs to make collagen; a supplement is the only way to get a consistent dose of collagen peptides. Bone broth cannot reliably match the 20 g supplement doses used in research⁴. Studies of collagen peptides have reported effects at about 2.5-15 g a day¹⁰.

A simple decision rule:

• If you want healthy collagen turnover: eat enough protein and at least one serving of a vitamin C food a day^{1, 3}.
• If you want to test a supplement for skin: know that the independent, high-quality trials found no benefit⁸. Our collagen for skin health page weighs the trials.
• If you want it for joint pain: the short-term benefit in osteoarthritis comes from trials whose overall evidence quality was very low⁹. See collagen for joint comfort.
• If you exercise regularly: 15 g of gelatin with vitamin C an hour before exercise is the protocol tested in healthy, active men^{12, 13}.

A sample day that covers the building blocks

Every number below comes from the sources above^{2, 1, 3}:

• Breakfast: eggs and 1 medium orange (70 mg vitamin C).
• Lunch: lentil or chicken salad with ½ cup of raw red pepper (95 mg vitamin C).
• Dinner: slow-cooked chuck or skin-on fish, with ½ cup of cooked broccoli (51 mg vitamin C).
• Snack or dessert: a cup of bone broth (5-10 g protein) or a homemade jelly with 1 tablespoon of gelatin (about 6 g protein).

That day gives over 200 mg of vitamin C, more than twice the 90 mg Daily Value³.

Related health goals

• Collagen Production
• Skin Elasticity
• Wrinkle Reduction
• Joint Comfort

We searched PubMed for bone broth, gelatin and collagen peptide studies, meta-analyses of collagen supplements for skin and osteoarthritis, and studies of what lowers collagen production. We read the NIH Office of Dietary Supplements vitamin C fact sheet, USDA FoodData Central's entry for plain gelatin and Harvard's Nutrition Source review of collagen. We read 13 study records and cited all of them, preferring meta-analyses of randomised trials and reporting the null results alongside the positive ones.

What the evidence can't tell us: no trial has tested whether eating collagen-rich foods changes skin or joints, and USDA tables do not list collagen content, so food amounts are given as protein from gelatin. Researched and written by the Remedy Routes Research Team, October 2026.

1. Harvard T.H. Chan School of Public Health, The Nutrition Source. Collagen. https://nutritionsource.hsph.harvard.edu/collagen/
2. U.S. Department of Agriculture, Agricultural Research Service. FoodData Central: Gelatins, dry powder, unsweetened (SR Legacy, FDC ID 169599). https://fdc.nal.usda.gov/food-details/169599/nutrients
3. National Institutes of Health, Office of Dietary Supplements. Vitamin C: Fact Sheet for Health Professionals. https://ods.od.nih.gov/factsheets/VitaminC-HealthProfessional/
4. Alcock RD, et al. Bone Broth Unlikely to Provide Reliable Concentrations of Collagen Precursors Compared With Supplemental Sources of Collagen Used in Collagen Research. Int J Sport Nutr Exerc Metab. 2019;29(3):265-272. doi:10.1123/ijsnem.2018-0139
5. Iwai K, et al. Identification of food-derived collagen peptides in human blood after oral ingestion of gelatin hydrolysates. J Agric Food Chem. 2005;53(16):6531-6. doi:10.1021/jf050206p
6. de Miranda RB, et al. Effects of hydrolyzed collagen supplementation on skin aging: a systematic review and meta-analysis. Int J Dermatol. 2021;60(12):1449-1461. doi:10.1111/ijd.15518 Our study summary.
7. Pu SY, et al. Effects of Oral Collagen for Skin Anti-Aging: A Systematic Review and Meta-Analysis. Nutrients. 2023;15(9). doi:10.3390/nu15092080 Our study summary.
8. Myung SK, et al. Effects of Collagen Supplements on Skin Aging: A Systematic Review and Meta-Analysis of Randomized Controlled Trials. Am J Med. 2025;138(9):1264-1277. doi:10.1016/j.amjmed.2025.04.034
9. Liu X, et al. Dietary supplements for treating osteoarthritis: a systematic review and meta-analysis. Br J Sports Med. 2018;52(3):167-175. doi:10.1136/bjsports-2016-097333 Our study summary.
10. Paul C, et al. Significant Amounts of Functional Collagen Peptides Can Be Incorporated in the Diet While Maintaining Indispensable Amino Acid Balance. Nutrients. 2019;11(5). doi:10.3390/nu11051079
11. Cosgrove MC, et al. Dietary nutrient intakes and skin-aging appearance among middle-aged American women. Am J Clin Nutr. 2007;86(4):1225-31. doi:10.1093/ajcn/86.4.1225
12. Shaw G, et al. Vitamin C-enriched gelatin supplementation before intermittent activity augments collagen synthesis. Am J Clin Nutr. 2017;105(1):136-143. doi:10.3945/ajcn.116.138594 Our study summary.
13. Lis DM, et al. Effects of Different Vitamin C-Enriched Collagen Derivatives on Collagen Synthesis. Int J Sport Nutr Exerc Metab. 2019;29(5):526-531. doi:10.1123/ijsnem.2018-0385
14. Fisher GJ, et al. Mechanisms of photoaging and chronological skin aging. Arch Dermatol. 2002;138(11):1462-70. doi:10.1001/archderm.138.11.1462
15. Knuutinen A, et al. Smoking affects collagen synthesis and extracellular matrix turnover in human skin. Br J Dermatol. 2002;146(4):588-94. doi:10.1046/j.1365-2133.2002.04694.x
16. Varani J, et al. Decreased collagen production in chronologically aged skin: roles of age-dependent alteration in fibroblast function and defective mechanical stimulation. Am J Pathol. 2006;168(6):1861-8. doi:10.2353/ajpath.2006.051302