Your body builds collagen from nutrients in food. After age 70, natural production falls by up to 1% each year. The good news is that eating the right foods — and pairing them well — can meaningfully support collagen renewal in your joints, tendons and ligaments.
The body's structural protein
Collagen is the most abundant protein in the body, making up approximately 30% of total body protein. It acts as the structural scaffolding that holds everything together. In the musculoskeletal system, collagen is the primary building material of three key structures.
- Tendons — fibrous cords connecting muscle to bone, transmitting the force of every movement you make.
- Ligaments — tough bands connecting bone to bone, giving joints their stability and preventing injury.
- Bone matrix — collagen forms the flexible framework onto which calcium and minerals are deposited, giving bone both strength and resilience.
There are more than 28 types of collagen. Type I (tendons, ligaments, bone) and Type II (cartilage) are most relevant to joint and mobility health.
Why collagen declines with age
Collagen is continuously broken down and rebuilt throughout life. From around age 40, this balance shifts: breakdown begins to outpace production. By the mid-seventies, several changes occur simultaneously.
The cells responsible for making collagen — fibroblasts in soft tissue and osteoblasts in bone — become less active. The quality of newly made collagen can also decline, with fewer chemical cross-links that give tendons and ligaments their tensile strength. Circulating levels of amino acids (the raw materials for collagen) are often lower in older adults due to reduced appetite and less efficient protein digestion.
Research published in Orthopedic Reviews (2024) found that dietary interventions supplying key amino acids can stimulate collagen synthesis in connective tissue, even in older individuals.[1]
The result can be stiffer joints, slower tendon recovery after activity, reduced bone flexibility, and a higher risk of ligament sprains or stress fractures. None of this is inevitable — diet makes a measurable difference.
What your body needs to make collagen
Collagen is not absorbed directly from food — it must be built by your cells. This process depends on a specific set of nutrients. Select each one below to see why it matters and where to find it.
Vitamin C (ascorbic acid) is the most critical nutrient for collagen production. It is required for the enzymes that stabilise the collagen triple-helix — the tightly coiled shape that gives collagen its strength. Without adequate vitamin C, collagen fibres form poorly and break down more easily.
A systematic review in the Orthopaedic Journal of Sports Medicine (2018) found that vitamin C supplementation accelerated bone healing after fractures and increased Type I collagen synthesis.[2] A subsequent study by Shaw and colleagues confirmed that vitamin C-enriched gelatin taken before exercise significantly raised collagen synthesis markers in ligament tissue.[3]
Recommended intake for adults over 70: 75–120 mg per day, easily met through diet.
Collagen is composed of a repeating sequence of amino acids: one third is glycine and approximately one quarter is proline. No other protein in the body shares this composition. Your body can make small amounts of both, but not enough to fully meet demand — particularly in older age.
Research published in PMC showed that raising glycine concentrations increased collagen synthesis in joint cartilage cells by 60–75%.[4] A diet rich in glycine also improved the structural integrity of tendons in models of Achilles tendinopathy.
The richest dietary sources are foods containing connective tissue: slow-cooked meat on the bone, fish skin, and homemade broth.
Lysine is an essential amino acid — the body cannot make it, so it must come from food. It plays two vital roles in collagen biology: it is a direct building block of the collagen chain, and it provides the starting material for the enzyme-driven cross-links that bind collagen fibres together in tendons and ligaments.
These cross-links are what allow tendons to withstand repetitive loading. Research in Osteoporosis International described collagen cross-linking as "a critical determinant of bone quality", reducing fracture risk independently of bone density.[5]
Copper is a trace mineral that acts as a cofactor for lysyl oxidase — the enzyme responsible for forming the cross-links between collagen fibres. Without adequate copper, collagen and elastin fibres cannot bond properly, resulting in weaker tendons, ligaments and bone matrix.
Research in PMC linked copper deficiency to bone malformations and increased osteoporosis risk, while adequate copper intake was positively associated with tensile strength and bone flexibility.[6]
Zinc is involved in collagen synthesis at several levels: it supports the activity of enzymes that transcribe collagen genes, and it plays a role in the maturation of collagen fibres. Zinc deficiency is relatively common in adults over 70 due to reduced dietary intake and decreased absorption efficiency.
A study published in PMC found a positive association between zinc levels and bone health in ageing men, with deficiency linked to reduced collagen deposition and impaired bone repair.[7]
What to put on your plate
No single food provides everything your body needs to make collagen. A varied diet combining animal proteins (for direct amino acids) with colourful plant foods (for vitamin C and antioxidants) is the most effective strategy.
Making it work in a solo kitchen
Eat protein at every meal
Older adults absorb amino acids less efficiently than younger people. Spreading protein evenly across breakfast, lunch and dinner — rather than mostly at one meal — improves the amount available for collagen production. Aim for at least 25–30 g of protein at each main meal.
Pair vitamin C with protein
Research by Shaw et al. found that consuming vitamin C alongside collagen amino acids — for example, a glass of orange juice with chicken soup — significantly raised collagen synthesis in ligament cells compared to protein alone.[3] This pairing costs nothing and requires no supplements.
Make broth, or buy a good stock
Slow-cooked broth from chicken carcasses, beef bones or fish frames is one of the few foods that directly supplies hydroxyproline — an amino acid almost uniquely present in collagen. A cup per day, used as a soup base or hot drink, is practical and inexpensive for a solo household.
Some researchers suggest consuming collagen-supporting nutrients 30–60 minutes before gentle exercise, such as a walk or light stretching. This is when blood flow to tendons and ligaments increases, potentially improving nutrient delivery to these tissues.
Stay well hydrated
Collagen fibres in tendons and ligaments require water to maintain their mechanical properties. Mild dehydration — common in older adults due to a reduced thirst sensation — can increase tendon stiffness. Aim for 6–8 cups of fluid per day.
If you have kidney disease, diabetes, or take medications affecting bone health (such as corticosteroids or bisphosphonates), please discuss any significant dietary changes with your GP or a registered dietitian before making them. Collagen supplements are widely available, but the evidence varies considerably; a good diet remains the safest foundation.
Foods and habits that reduce collagen
- Excess sugar — Advanced glycation end-products (AGEs), formed when sugar binds to proteins, stiffen collagen fibres and reduce their elasticity. Minimising added sugars protects existing collagen.
- Regular alcohol — Interferes with vitamin C absorption and impairs the liver's ability to produce proteins needed for collagen synthesis.
- Smoking — Reduces blood supply to connective tissue and generates free radicals that damage collagen. Tendons in people who smoke show measurably poorer collagen quality.
- Ultra-processed foods — High in sodium and refined carbohydrates, low in the micronutrients needed for collagen production.
Collagen nutrients at a glance
| Nutrient | Role in collagen | Best food sources |
|---|---|---|
| Vitamin C | Stabilises the triple-helix structure | Kiwi, citrus, capsicum, broccoli, strawberries |
| Glycine & Proline | Primary structural amino acids | Bone broth, chicken skin, pork, fish, gelatin |
| Lysine | Cross-linking; tendon tensile strength | Eggs, dairy, legumes, salmon, chicken |
| Copper | Activates lysyl oxidase enzyme | Nuts, seeds, shellfish, dark chocolate, mushrooms |
| Zinc | Activates collagen genes; fibre maturation | Red meat, pumpkin seeds, legumes, dairy, wholegrains |
Scientific sources
- Martínez-Puig D, et al. (2023). The Effects of Type I Collagen Hydrolysate Supplementation on Bones, Muscles, and Joints: A Systematic Review. Orthopedic Reviews (Open Access). View article ↗
- DePhillipo NN, et al. (2018). Efficacy of Vitamin C Supplementation on Collagen Synthesis and Oxidative Stress After Musculoskeletal Injuries: A Systematic Review. Orthopaedic Journal of Sports Medicine (PMC Open Access). View article ↗
- Shaw G, et al. (2017). Vitamin C-enriched gelatin supplementation before intermittent activity augments collagen synthesis. American Journal of Clinical Nutrition. View article ↗
- Albaugh VL, et al. (2019). High glycine concentration increases collagen synthesis by articular chondrocytes in vitro. PMC Open Access. View article ↗
- Viguet-Carrin S, et al. (2009). Collagen cross-links as a determinant of bone quality. Osteoporosis International. View article ↗
- Henneicke H, et al. (2021). Bone Health in Aging Men: Does Zinc and Cuprum Level Matter? PMC Open Access. View article ↗
- Sylvester Ndiaye J, et al. (2022). Regulators of Collagen Crosslinking in Developing and Adult Tendons. PMC Open Access. View article ↗