Vitamins and minerals
As all plants, even coffee contains some amounts of vitamins and minerals that integrate nutritional values of the beverage.
For example, coffee is a very good source of vitamin B3 (niacin) that is involved in converting food into energy. Moreover, it regulates a lot of organism functions like hormones production, proper functioning of digestive and nervous systems, favors healthy skin and is effective in lowering levels of cholesterol. The deficiency of niacin can cause various disorders such as unmotivated tiredness, digestive problems, or even depression.
Other vitamins found in coffee are B2 (riboflavin); B4 (choline); B5 also called pantothenic acid.
Although it can not be considered as an important mineral source, a cup of coffee contains moderate amounts of magnesium, potassium and phosphorus.
As usual for coffee, there’s a certain controversy. In fact, much has been discussed about the caffeine effect on calcium absorption. Calcium plays a role in nerve cell signaling, allows for cell-to-cell communication within the body and contributes to bone mineralization. Regard to its association with caffeine is necessary to clarify that: Coffee itself contains a small amount of calcium. There is no evidence that caffeine has any harmful effect on bone status or on the calcium economy in individuals who ingest the recommended daily allowances of this mineral. Furthermore, the negative effect of caffeine on calcium absorption is small enough to be fully offset by as little as 1-2 tablespoons of milk.