Zinc, calcium and magnesium cut chances of type 2 diabetes, and calcium intake by men and women and high vitamin D levels in men lowered insulin levels, in three studies.
In a diabetes study, doctors knew that zinc helps cells use energy and wanted to see if zinc lowered the chances of type 2 diabetes. Researchers measured the diets of over 82,000 women, aged 33 to 60, and followed up for 24 years. Taking into account differences in family history and lifestyle, scientists found those who consumed the most zinc were 28 percent less likely to develop type 2 diabetes compared to those who consumed the least.
In a calcium and magnesium study, researchers evaluated the diets of over 64,000 men and women who began the study without type 2 diabetes and followed up for seven years. Women who consumed the most calcium were 27 percent less likely to develop type 2 diabetes than women who consumed the least. Also, men and women who consumed the most magnesium were 20 percent less likely to develop type 2 diabetes than men and women who consumed the least.
In an insulin study, doctors thought that calcium and vitamin D might lower risk for type 2 diabetes. Type 2 diabetics often produce high levels of insulin to process excess blood sugar or have high insulin levels because the body can’t properly use it. The pancreas produces insulin along with a molecule called C-peptide—a by-product of insulin production—in equal amounts, making C-peptide a good measure of insulin levels.
In the study, researchers found that healthy women and men who consumed the most calcium had C-peptide levels 20 percent lower and 17 percent lower, respectively, than women and men who got the least calcium. Men with the highest blood levels of vitamin D had about 20 percent lower C-peptide levels than men with the lowest levels. Combining calcium and vitamin D measurements, men had 35 percent lower C-peptide levels and women had 12 percent lower levels.
Researchers concluded that the body appears to produce more normal levels of insulin when levels of calcium and vitamin D are good.