Calcium and Vitamin D

Calcium and Vitamin D

Gabe Mirkin, M.D.

Many people take calcium supplements to help prevent osteoporosis. 
They may be increasing their risk for certain cancers and infections 
unless they also get extra vitamin D. Calcium absorption uses up 
vitamin D and lack of that vitamin impairs immunity, which can cause 
cancer and infections. 

To prevent a deficiency, you need at least 400 IU of vitamin D per 
day, whether you take calcium supplements or not. Many researchers 
now recommend 2000 IU per day. You can get this by exposing some 
skin to sunlight each day. Dietary sources of vitamin D include 
fatty fish, eggs, liver and butter. Vitamin D-supplemented milk is 
a poor source of that vitamin because the calcium in milk uses up 
more than the vitamin D that is added. 

You need 1000 mg of calcium each day, the amount of calcium found in 
four glasses of milk. Many people do not meet their needs for 
calcium from the foods that they eat. If you take calcium 
supplements, take the recommended daily requirement for vitamin D 
of at least 400 international units per day. 

A glass of milk contains the same amount of calcium as a cup of 
yogurt, an ounce of hard cheese, a cup and a half of cottage cheese, 
four ounces of fish, or a 600 mgm calcium carbonate pill. To check 
how much calcium you eat, add up the calcium in your diet in 
milk-glass-units from the foods just mentioned, then add an extra 
unit for the calcium you get from other foods. A sixty-year old 
woman who drinks two glasses of milk and eats an ounce of hard 
cheese gets three milk units. Add an additional unit for the calcium 
in other foods and she needs two more units, which she can get by 
taking two generic calcium carbonate pills. Don't waste your money 
on expensive chelated calcium pills or supplements that combine 
magnesium with calcium. Magnesium is not necessary for calcium 
More on vitamin D

Checked 9/3/10