Friday, September 20, 2013

Calcium - the Great Milk Myth


Calcium is one of the most important minerals in the body and is involved in much more than just bone formation.  Calcium is required for our nerves to pass signals, for our blood to clot, our heart to pump, and our muscles to contract.  Every cell in the body requires calcium, which is why the amount of calcium in the blood is tightly controlled.  When levels begin to drop the body pulls calcium from the bones, which is our largest source of calcium storage.  This process is called bone resorption, and can lead to weak, brittle bones (osteoporosis) as we age.  We need to get large amounts of calcium from our food every day to prevent osteoporosis.

The recommended daily allowance (RDA) for calcium varies by age:
0–6 months* 200 mg
200 mg

7–12 months* 260 mg
260 mg

1–3 years 700 mg
700 mg

4–8 years 1,000 mg
1,000 mg

9–13 years 1,300 mg
1,300 mg

14–18 years 1,300 mg
1,300 mg
1,300 mg
1,300 mg
19–50 years 1,000 mg
1,000 mg
1,000 mg
1,000 mg
51–70 years 1,000 mg
1,200 mg

71+ years 1,200 mg
1,200 mg

How can I get enough calcium? Can’t I just drink milk?
Cow’s milk isn’t the only source of calcium.  In fact, cow’s milk has many potential problems.  Many people lack the enzyme to digest lactose, the sugar naturally occurring in milk.  This is condition is called “lactose intolerance,” and can lead to bloating, abdominal discomfort, and flatulence.  Though all healthy babies have the enzyme (lactase) to digest the lactose in human milk, the amounts of lactase tend to gradually decrease after infancy (beginning at around 2 years of age).  It is estimated that 90% of Asians and Africans are lactose intolerant, 70% of Hispanics and Jewish persons, 65% of Southern Indians, 30% of Central Europeans, and 5% of Northern Europeans.  Persons who are not lactose intolerant may still have allergies or food sensitivities to the proteins casein or whey in dairy products.