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:
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.
There are other concerning issues with milk consumption as well. Cow’s milk has been linked to autoimmune conditions, including type I diabetes. It can also cause iron deficiency, atherosclerosis, and may exacerbate irritable bowel syndrome, autism, asthma and allergies. Milk also contains saturated (“unhealthy”) fats that can lead to heart disease and Alzheimer’s. Though it is often touted as a good food for the bones, cow’s milk is also high in phosphorus, which actually contributes to osteoporosis.
What are other sources of calcium?
There are many other great ways to get calcium without the negative effects of cow’s milk. Some ideas: substitute blackstrap molasses for sugar in recipes to increase both calcium and iron. Skip the tuna fish and used canned salmon or sardines (with bones) on crackers or toast for a delicious snack. Buy calcium-fortified orange juice instead of regular – the naturally occurring vitamin C will increase absorption of calcium. Avoid taking calcium with iron or other minerals because they compete for absorption in the gut.
Remember that calcium isn’t the only player in the osteoporosis prevention game. Vitamin D, vitamin K, magnesium, vitamin C and protein are all important to decrease the risk of osteoporosis and fractures. Vitamin D increases your body’s ability to absorb and use calcium appropriately – I always recommend all my patients to have their vitamin D levels checked so we can optimize their health.
Here is a helpful list of other sources of calcium:
Blackstrap molasses, 2 tbsp 400 mg
Sardines, 3 ounces 324 mg
Collard greens, 1 cup 357 mg
Calcium-fortified orange juice, 1 cup 300 mg
Soy or rice milk, fortified, 1 cup 200-300 mg
Firm tofu, 1/2 cup 253 mg
Canned salmon, 3 ounces 205 mg
Turnip greens, 1 cup 215 mg
Kale, 1 cup 179 mg
Soybeans, 1 cup 175 mg
Okra, 1 cup 172 mg
Bok choy, 1 cup 158 mg
Mustard greens, 1 cup 152 mg
Tahini, 2 tbsp 128 mg
Broccoli, 1 cup 94 mg
Almonds, 1/4 cup 89 mg
Almond butter, 2 tbsp 86 mg