Author: Frank W. Jackson, M.D.
Calcium is essential to the body. It is the most common mineral in the body and is needed in tiny amounts for the function of most vital organs such as heart and brain. However, the vast majority of calcium is used by the bones and teeth. During early childhood and adolescence, vigorous bone growth occurs. However, bone is a living tissue and calcium leaves the bone as new bone is being created. By the mid 30’s, a shift occurs whereby more calcium begins to leave bone than is deposited. Bones begin to weaken. In the earliest stages, this is called osteopenia. As it worsens, it becomes osteoporosis. This is when bone fractures of the hip and spine begin to occur. It is never too late to reverse this process, though starting early in life and when young will give you the best chance of having strong bones later in life.
Risk Factors for Osteoporosis and Osteopenia
- Older age
- Non-Hispanic, Caucasian and Asian ethnicity
- Small bones – i.e. females
- Family history of osteoporosis or osteopenia
- Long-term estrogen hormone use
- Cigarette smoking
- Alcohol abuse
- Sedentary lifestyle or bedridden
- Low calcium intake
- Low vitamin D blood level
- Certain medications such as prednisone, excess thyroid, Dilantin and others
Gut Bacteria and Calcium
A remarkable new area of modern research is in the human colon. Here, there are over 2000 species of bacteria and trillions upon trillions of bacteria. They live and thrive in the colon and produce a large number of health benefits. It is now known that when significant amounts of certain vegetable fibers or dietary supplements reach the colon that the very best bacteria grow vigorously. These thriving bacteria in turn cause extra calcium to be absorbed through the colon wall.
Soluble Prebiotic Fiber
All plant fiber arrives in the colon unchanged. There, it is the soluble (meaning water soluble) fibers that are used by certain of the gut’s bacteria to enhance the absorption of calcium. The two fibers that have been most studied are inulin and oligofructose. In fact, when a group of young teenagers took this fiber supplement daily, they had a 20% increase in bone density (bone strength) after one year.
Vitamin D and calcium are intimately connected. You need to have a good level of vitamin D in your blood to absorb and use calcium. In Caucasian and light-skinned people, the sun’s rays will make vitamin D in the skin. Dark-skinned people and African-Americans need to get their vitamin D from foods and vitamin D pills. This is important as vitamin D deficiency is very common. For detailed information on vitamin D from the National Institutes of Health, google search: Dietary supplement Fact Sheet: Vitamin D.
Selected Foods High in Vitamin D
- Cod liver oil
- Salmon, Mackerel, Sardines, Tuna
- Vitamin D enriched milk, fruit juices, yogurt
What To Do – The Good Things
- Consume 1000-1500 mg of calcium per day in food and/or a supplement
- Active lifestyle – walking, bicycling, gym workout, etc. You want to stress your bones. Weight lifting by itself does not do this very well.
- Eat soluble plant fiber or take a prebiotic supplement such as Prebiotin-Bone Health.
- No cigarettes
- Moderate alcohol only
- Check your medications with your physicians.
- Moderate caffeine intake – coffee and sodas
By far, the most important consideration is to get enough calcium into your body every day. A minimum of 1000 mg a day is recommended going up to 1500 mg a day when needs are high, such as in recovery from fractures, athletics and pregnancy. The chart below provides information on calcium content in various common foods.
|Calcium Content of Foods|
|Foods||Serving Size||mg of Calcium|
|Yogurt, Low Fat||1 cup||450|
|Cheese, Grilled Sandwich||1||371|
|Cheese, Ricotta||1/2 cup||337|
|Yogurt, Fruit||1 cup||315|
|Cheese, Cheddar||1 1/2 oz||305|
|Milk, Skim or 2%||1 cup||300|
|Orange Juice with Calcium||1 cup||300|
|Soy Beverage with Calcium||1 cup||250-300|
|Cheese, Gruyere||1 cup||287|
|Tofu, Firm||1/2 cup||240|
|Cheese, Mozzarella||1 ounce||207|
|Tofu, with Calcium||1/2 cup||204|
|Macaroni and Cheese||1/2 cup||179|
|Collard Greens, Frozen/Boiled||1/2 cup||179|
|Ice Cream, Vanilla||1 cup||176|
|English Muffin, Whole Wheat||1||175|
|Cheese, American||1 oz||174|
|Rhubarb, Cooked||1/2 cup||167|
|Oatmeal, Instant||3/4 cup||163|
|Cottage Cheese, 2%||1 cup||163|
|Rice Beverage with Calcium||1 cup||150-300|
|Pudding Made with Milk||1/2 cup||147-160|
|Custard, Baked||1/2 cup||149|
|Pizza, Cheese||1 slice||111-147|
|Molasses, Blackstrap||1 Tbsp||137|
|Spinach, Cooked or Frozen||1/2 cup||122|
|Tofu, Regular||1/2 cup||108|
|Yogurt, Frozen (Fat Free/Low Fat)||1/2 cup||105|
|Milk, Instant (Dry/Nonfat)||2 Tbsp||105|
|Broccoli, Cooked or Fresh||1 cup||90|
|Kale, Cooked||1/2 cup||90|
|Sesame Seeds, Dried||1 Tbsp||88|
|Bok Choy, Cooked or Fresh||1/2 cup||80|
|Mustard Greens, Cooked||1/2 cup||75|
|Bread, White||2 slices||70|
|French Toast||1 slice||65|
|Hot Dog, Turkey||1||58|
|Halibut, Baked||3 oz||51|
|Fig Bar Cookie||4||40|
|Bread, Whole Wheat||2 slices||40|
|Cream Cheese||2 Tbsp||23|
|Cream, Half and Half||1 Tbsp||16|
|Chicken Breast, Baked||3 oz||14|
|Pasta, Cooked||1 cup||10|
|Beef, Lean Ground||3 oz||9|
|This Sample Diet Provides the Following|
There are many different forms of calcium preparations sitting on the pharmacy shelf. How do you decide which is best for you? If you are getting, on average, 1000-1500 mg of calcium a day in your foods, you likely do not need a supplement. However, to get this much calcium, the diet must be rich in dairy products such as milk, yogurt, some cheeses and fish. If you select a calcium supplement, below are some key facts to consider.
There are two main preparations of calcium:
Calcium is also available as calcium lactate and calcium gluconate.
Elemental Calcium – This is an important term. The label may say calcium 1000 mg, but the important term is “elemental calcium“. This is the amount of calcium that is actually available from the preparation. For instance:
Weight Elemental Calcium
Calcium Carbonate 1000 mg 400 mg (40%)
Calcium Citrate 1000 mg 210 mg (21%)
If you do not find the two words “elemental calcium” on the label, assume you must multiply the calcium weight listed by 40% for calcium carbonate and 21% for calcium citrate to get the true amount of elemental calcium.
- Expense – Calcium carbonate is the least expensive. Calcium citrate is more expensive per pill while providing only half the elemental calcium that carbonate preparation does.
- When and how to take it – Take calcium carbonate with meals, no more than 500 mg at a time. Twice a day is a reasonable dosing. Calcium citrate can generally be taken with or without food.
© Frank W. Jackson, M.D.