What is collagen? It's your connective tissue, tendons, ligaments, cartilage. One-third of all of your collagen is made by one amino acid, glycine. And glycine is not an essential amino acid, which means that our bodies can make it. But here's the thing, our bodies really don't make enough glycine. And if you're not getting it from the diet, chances are you're going to be deficient. Because normal proteins, red meat or chicken or fish or even eggs or even dairy, are not very high in glycine. You'd have to be eating the skin on the chicken and the cartilage like on the chicken bones or organ meats. And a lot of people do not do that. So we can be consuming a lot of protein, but not getting this one amino acid that could lead to all sorts of issues.