According to National Health and Nutrition Examination Survey data, 79 percent of adults living in the United States do not meet the required daily intake of magnesium.
Although these intake levels are not low enough to result in clinical deficiencies, they are worrying when you look at calcium-to-magnesium ratios in the United States.
High calcium to magnesium ratios have been linked with higher risks of colorectal cancer and, in some studies, heart disease.
This is largely due to the fact that calcium and magnesium compete for absorption (high ratios don't allow magnesium to do its job properly).
Diets with high calcium:magnesium ratio put individuals at a higher risk for oxidative damage (one of the most significant causes behind the development many diseases).
The ratio should ideally be approximately 2:1 (hence the calcium DRI of 1,000 milligrams and the magnesium DRI of 500 milligrams).
Nuts, beans, potatoes, whole grains, and spinach are the best sources of magnesium.