And this glycation increases in all of us as we age. These cross links bend proteins out of shape, rendering them useless. Saari and Dahlen found that both the early and advanced stages of protein glycation increased significantly in the rats fed a copper-deficient diet. One sensitive indicator of advanced glycation was at least sixfold higher in the copper-deficient rats. It was nearly undetectable in the control rats.
Human diets contain more copper than the copper-deficient diets given the rats.
But the average copper content of U.S. diets falls below the suggested range of 1.5 to 3.0 milligrams daily. Saari speculates that years of eating a diet low in the mineral may contribute to the age-related decline in tissue function by increasing glycation. So far, he has looked only at glycation of blood hemoglobin and serum proteins. But it can also happen to structural proteins that form the tissues.