At this point in history, we humans in the western culture have grade-D connective tissue. This is because our food management practices destroys vitamin C, a major requisite of strong collagen. Our high heat quick cooking styles also denatures amino acids in meats. We throw away l-proline, the major component of collagen, when we eat only the muscle meat from poultry, fish and meat.
Our digestion weakens when we use antibiotics and kill off the intestinal flora that produces enzymes necessary for transforming glucosamine into n-acetyl glucosamine, a major molecule that repairs the lining of the joints.
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