Question: How much vitamin C should I take with collagen?
There's no evidence that you need to take vitamin C with collagen. There is a study by Keith Baar, who showed that 15 grams of gelatin, not collagen, but I suspect the collagen is exactly the same, 15 grams of gelatin but not 5 grams, the dose is important, with 50 milligrams of vitamin C taken before exercise improved collagen synthesis in the tendons. They included 50 milligrams of vitamin C because it's made for collagen synthesis, but they don't show that you needed the vitamin C. They just had the vitamin C in there. I don't know if it even matters in that context whether you need the vitamin C. I also have no reason to think that you need 50 milligrams instead of 10 or that 100 milligrams wouldn't work better because they didn't test the different doses. They tested the different doses of gelatin. I see no reason to think a high dose of collagen is any different in this respect.
Let's assume that it's the same. What that means that I'm very confident that you need 15 grams instead of 5 grams when you take it before exercise to increase synthesis of collagen in tendons if that's what you care about. I have no confidence about how much vitamin C you need if you need any. But if you want to do what they did, then I do feel confident that 50 milligrams is enough to get some effect. I just don't know if it's enough to get maximal effect and I don't know if it's necessary at all or in that dose to get that effect.
If it's for joint health and if it's taken before exercise, the timing is important because what you're trying to do is leverage the exercise to get more blood flow of the nutrients to the joints. That's why the timing matters. In that case, you take the vitamin C with the collagen, 50 milligrams is the dose we know works. We don't know if it's necessary, and we don't know if it's optimal. We just know that it works. If you're not taking it for joint health and you're not taking it specifically before exercise, you still need vitamin C. But the timing doesn't matter and pairing it to the collagen doesn't matter.
This Q&A can also be found as part of a much longer episode, here: https://chrismasterjohnphd.com/podcast/2019/03/30/ask-anything-nutrition-march-4-2019
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