A recent study in Sweden published in the British Medical Journal supports conclusions from a previous study earlier this year that suggests that when it comes to calcium – more is not better.
Using data from the Women’s Health Initiative Calcium/Vitamin D Supplementation Study — a seven-year trial in 36,282 postmenopausal women — Dr. Ian Reid from the University of Auckland in New Zealand and colleagues concluded that women who took calcium supplements had a 13-to-22 percent greater risk of having a heart attack than women who did not. The risk went up regardless of whether the women also took vitamin D, which promotes calcium absorption and bone mineralization. The researchers also found a milder increase in stroke risk among women taking the supplements.
The more recent Swedish study looked at the relationship between calcium intake and risk for fractures and overall bone health. The results were surprising. The study suggests that women with the highest intake of calcium (above 1100 mg a day) actually had a hint of increased risk for hip fracture. The bottom line of this study was that more moderate levels of calcium intake were best for bone health and again, more was not better. The recommendation of calcium intake may be best to not exceed the recommended amount of 1000-1200 mg a day total from all sources. Assuming that many women will get about 700 mg a day from dietary sources, an additional 500-600 mg a day from calcium supplementation would be safe. Many women often have reported 1200-1500 mg a day just from the supplements alone, resulting in too high a daily dose.
Calcium supplements have been promoted especially for women to prevent bone fracture from osteoporosis. Calcium supplementation comes from multivitamins, calcium supplements, fortified fruit juices and cereals, and antacids. We also get calcium from dairy foods, of course. So combining all these together could result in an amount of calcium that exceeds the Upper Tolerable Limits, which is 2000 mg a day for all age groups and far exceeds the RDA recommendation.
Food Sources of Calcium
Milk, yogurt, and cheese are rich natural sources of calcium and are the major food contributors of this nutrient to people in the United States . Nondairy sources include vegetables, such as Chinese cabbage, kale, and broccoli. Spinach provides calcium, but its bioavailability is poor. Most grains do not have high amounts of calcium unless they are fortified; however, they contribute calcium to the diet because they contain small amounts of calcium and people consume them frequently. Most experts recommend we get most nutrients from foods and not be reliant on supplements. In the case of calcium, it’s very important to read the food labels and determine how much total calcium you are consuming daily for optimum heart and bone health