Healing tendon injuries with nutrition
Written by Joachim Bartoll, January 2016
Classic Muscle Newsletter, March 2016 (issue #18)
Tendon injuries can be one of the worst hurdles for anyone who regularly participates in exercise or sports. They heal slowly and can seem to last forever, and the current therapies to treat them don’t seem to be very effective. While minor muscle injuries are more common than tendon injuries, such as strains or sprains, they often heal rapidly, while tendon injuries can go on for months or longer. The reason for the differences in healing time comes down to blood supply. Muscles are enriched with a huge network of blood vessels that carry oxygen and nutrients to any injured area, which greatly aids the healing process. Tendons on the other hand have a very limited blood supply, making the healing process very slow.
There are currently a number of therapeutic approaches to treat injured tendons, but an in-depth discussion of them is beyond the scope of this article. Briefly, these treatments include providing an infusion of blood platelets (platelet rich plasma) that provides various growth factors thought to promote a more rapid regeneration and healing of injured connective tissue, including tendons. It’s often provided to professional elite athletes in the hope of more rapid recovery from injuries and thus return to play. While platelet rich plasma has shown some promise in healing injured tendons, it doesn’t always work well. One reason for this is the lack of standardization, with some containing far more growth factors than others.
Other treatments for tendon injuries include extracellular matrix/scaffold treatment, which provides the underlying foundation elements of tendon in the help that new cells can be encouraged to proliferate within the matrix. Some treatments feature supplying direct growth factors into tendons, including IGF-1. One of the most promising treatments is stem cell therapy, which can produce new connective tissue in injured tendons. Stem cell treatment for tendon injuries is not widespread, but is on the rise in Europe. However, the results from this treatment varies widely, suggesting that it too, isn’t really ready for a wider market yet. No doubt in the future, several of these emerging therapies will be perfected and available for anyone. But in the meantime, the best way to deal with tendon injuries is to prevent them, and use nutritional elements to nurture more efficient repair.
Going the nutritional route – get your protein in
One problem with the existing body of research related to nutritional treatment of tendon injuries is that most of the research has been done with either in-vitro isolated connective tissue cells, or with animals. There is some human research, but not a lot. The animal studies, however, do show significantly improved healing responses with the application of specific nutritional principles and nutrients. This is not really surprising, since connective tissue is largely composed of a tough protein called collagen. Also, various nutrients play important roles in helping to repair and maintain tendons. One example is how certain minerals are required to activate enzymes in connective tissue, including tendons, that are involved in synthesizing collagen and base proteins contained in tendons. Since collagen is a protein, ingesting more protein is clearly advised if you suffer a tendon injury. While most fitness enthusiast probably have this covered, not many in sports do.
Actually, in one study, 22 young men who were engaged in a resistance training program were provided with 19.5 grams of whey protein per day. Ingesting this level of added protein was shown to increase the patellar (knee) and quadriceps (frontal thigh muscle) tendon cross-sectional area. The increase in patellar tendon thickness improved by 14.9% in those who ingested the whey supplement, which was a hydrolyzed whey product, compared to an 8.1% increase in those who did the same workout, but ingested a placebo.
Vitamin C and vitamin D
Another important nutrient to promote tendon repair is vitamin C. Vitamin C is required to activate enzymes that produce collagen, and a typical sign of scurvy (vitamin C deficiency) is compromised collagen production in the body. Besides helping to produce collagen in tendons, vitamin C also promotes the synthesis of the underlying structural material of tendons, proteoglycans. Proteoglycans are proteins that are naturally glycated, meaning that they are proteins that contain a sugar within their structure.
Usually, the process of producing excess advanced glycation end products or AGEs in the body normally reduces the strength of tendons and other tissues in the body. But in the case of proteoglycans, the glycation effect works in reverse, providing increased strength that adds to the structural integrity of connective tissue, including tendons.
Certain supplements can also boost production of proteoglycans in tendons and elsewhere. A study of rats supplied with high doses of vitamin C showed increased healing of ruptured Achilles’ tendons in the rodents.
It should be noted that the consumption of carbohydrates increases the body’s need of Vitamin C by a manifold. On a ketogenic or low-carbohydrate diet, the need for Vitamin C is extremely low, allowing the body to use more Vitamin C for repair and other uses. It should also be noted that any excess vitamin C will be converted to oxalate, a chemical that we usually find in most vegetables and other plant food. Oxalates binds to calcium and form plaque in our arteries and also kidney stones.
You probably know about my affection for the powers of vitamin D. And yes, another rat study that involved 28 rats for 6 weeks found that a lack of vitamin D resulted in blunted healing and delayed increase in the biomechanical strength of the rotator cuff tendons (shoulders) in the rats. This is not surprising since high levels of vitamin D signals the body that it’s summer and food availably is plentiful and therefore the body can afford to increase its metabolism and repair itself. A lack of vitamin D does the opposite – every bodily function slows down.
The best way to get plenty of Vitamin D is by getting enough sun exposure. Supplementation can be a viable option for those in colder climates or for those being forced to work indoors most of the day. Just make sure that you get extra vitamin K2 as vitamin D increases circulating calcium and vitamin K2 make sure our body can use it for repair. As with all vitamins, vitamin K2 should be of animal origin in the form of MK4, otherwise only a miniscule amount will be absorbed.
What about glucosamine and chondroitin?
Rabbits provided with high doses of oral glucosamine/chondroitin sulfate supplements (GCS) resulted in accelerated tendon healing. While GCS is a popular human supplement for treating joint and tendon injuries, the results of human studies that provided this nutrient combo, mainly to those suffering from arthritis, show mixed results. But GCS does promote the synthesis of proteoglycans in injured tendons, so it may help. The thing to keep in mind with any of these nutritional approaches is that because of the inherent poor blood circulation of tendons, it takes time for these supplements to provide beneficial effects, in some cases as long as 3 to 4 months before any apparent improvement is evident. The studies that have shown little or no effect from these supplements are often short-term studies, lasting no more than two weeks to a month. Such studies wouldn’t be expected to show any results.
Minerals and trace minerals
A couple of studies has shown that chickens that lack sufficient biotin, folate, or manganese show increased incidence of tendon inflammation. Manganese, a trace mineral, is required to activate enzymes involved in tendon protein production. Any diet that doesn’t contain sufficient protein and trace minerals will lead to deficits in connective tissue strength, including that of tendons. Besides manganese, other trace minerals that are vital to tendon health include zinc and copper, both of which are involved in the production of collagen.
Zinc works with vitamin C in producing collagen throughout the body, and both nutrients should be increased following any type of injury, including surgery.
The importance of minerals is why Vegans deteriorate and age so quickly especially in the skin and joints, since the phytic acid and oxalates found in plant foods (especially vegetables, fruit, grains, seeds and nuts) binds to minerals and render them useless for the body.
Specific amino acids and Nitric Oxide
Animal studies show that providing the amino acids, glutamine, arginine, and branched-chain amino acids accelerates healing of connective tissue in skin. Arginine is particularly potent in this regard, possibly because it may promote a growth hormone release that is known to promote connective tissue healing, and also because it may upgrade nitric oxide (NO) release. NO will boost blood flow, and subsequent delivery of oxygen and nutrients to injured tissue. Any kind of NO-booster may therefore be beneficial during the healing process.
MSM and putting it together
The best nutritional approach in relation to tendon protection and healing would involve a synergistic combination of these nutrients discussed above, rather than relying on any one particular nutrient. For example, one study found that a supplement that contained 1 gram of arginine; 1.1 grams of MSM, 600 milligrams of hydrolyzed collagen; 120 milligrams of vitamin C; and 100 milligrams of bromelain (a protein digesting enzyme found in pineapples) lead to faster tendon repair in 90 patients who underwent rotator cuff surgery. MSM, which is an oral form of the old topical pain reliever, DMSO, has been shown in some studies to help relieve the pain associated with arthritis and may also speed healing of tendon injuries. A good daily dose for this is about 6 grams a day in divided doses.
Other nutrients and supplements that may help include omega-3, which lowers inflammation, thereby increasing healing time and lowering pain. The dose would be at least 5 grams a day.
Magnesium also helps to protect tendon health, with rats lacking the mineral showing degeneration of tendons.
Although, the research on these various nutritional approaches is preliminary and with varying results, the good news is that none of them show any side effects. They’re all natural. And the absolute best sources of both collagen and minerals are bone marrow, homemade bone broth, and meat with skin. For vitamins the best sources are egg yolks, liver and other organ meats. Specific joint and tendon supplements might also be helpful, such as MSM, Nitric Oxide products and so on. As such, you have nothing to risk by trying them. Most of them also bring other important health benefits.
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