Why calcium needs increase after 65
As a woman ages, especially after menopause, her body's ability to absorb and retain calcium declines. Estrogen, a hormone that helps protect against bone loss, decreases sharply after menopause, accelerating the rate at which bone mineral density is lost. For women, bone loss can occur at a rate of approximately 1% per year after menopause. This places women over 65 at a higher risk for conditions like osteoporosis, which can lead to fractures and impaired mobility.
To counteract this increased vulnerability, dietary reference intakes are higher for older women than for younger women. The higher 1,200 mg recommendation for women over 51 is a proactive measure to help support bone maintenance and reduce fracture risk.
Dietary sources vs. supplements
The most effective and recommended way to get calcium is through food. Your body absorbs calcium best from food sources. However, if diet alone is not enough, supplements can help bridge the gap. When considering calcium intake, it's vital to focus on the total amount from both food and supplements, staying mindful of the recommended upper limits.
Excellent food sources of calcium
- Dairy products: Low-fat milk, yogurt, and cheese are classic and reliable sources of calcium. A single cup of low-fat yogurt can provide over 400 mg of calcium.
- Fortified foods: Many products today are fortified with calcium to help boost intake. Look for fortified orange juice, breakfast cereals, and plant-based milks like soy and almond milk.
- Leafy green vegetables: Vegetables such as collard greens, kale, and bok choy contain good amounts of calcium. It's worth noting that some greens like spinach also contain oxalates, which can interfere with calcium absorption.
- Fish with edible bones: Canned sardines and salmon, where the bones are soft and edible, are surprisingly rich sources of calcium.
- Tofu: Tofu that is prepared with a calcium salt can provide a significant amount of calcium per serving.
How to choose a supplement
If you need a supplement, two main forms are common: calcium carbonate and calcium citrate.
- Calcium carbonate: This is more common and less expensive, but it is best absorbed when taken with food. Since the body can only absorb about 500-600 mg of calcium at a time, it is better to take a smaller dose multiple times per day rather than one large dose.
- Calcium citrate: This form is more easily absorbed and can be taken with or without food, making it a good option for older adults who may have lower stomach acid.
The importance of vitamin D and exercise
Calcium is not a standalone nutrient; it requires adequate vitamin D for proper absorption. For adults over 70, the recommended daily allowance for vitamin D is 800 IU. Good sources include sunlight, fortified foods, and fatty fish. Combining calcium and vitamin D supplementation can be more effective than calcium alone for bone health.
Furthermore, weight-bearing exercise is crucial for building and maintaining strong bones. Activities such as walking, jogging, dancing, and light weight training can help slow bone loss and increase bone density. A holistic approach that includes diet, supplements, and exercise is most effective for protecting bone health in older women.
Calcium intake comparison: Food vs. Supplements
To help understand your options, here's a comparison of calcium sources and their pros and cons.
| Feature | Food Sources (e.g., dairy, greens) | Calcium Supplements (e.g., carbonate, citrate) |
|---|---|---|
| Absorption | Generally better, as the body is designed to absorb nutrients from whole foods. Less risk of taking too much at once. | Absorption varies by type (citrate is easier) and is limited to about 500-600 mg per dose. |
| Additional Nutrients | Provides a host of other beneficial vitamins and minerals (e.g., vitamin K, magnesium) alongside calcium. | Primarily contains just calcium and often vitamin D. Lacks the full nutritional profile of food. |
| Convenience | Requires conscious meal planning to meet daily needs, which can be a challenge. | Easy to take and can consistently provide a measured dose. Can be taken to fill dietary gaps. |
| Potential Risks | Very low risk of adverse effects from food alone. Risks are associated with overall dietary patterns. | Higher risk of consuming more than the Tolerable Upper Intake Level (2,000 mg for women over 51), which can increase the risk of kidney stones. Some studies have also controversially suggested potential cardiovascular risks with high supplemental calcium intake. |
Conclusion
For women over 65, aiming for 1,200 mg of calcium daily is a crucial step toward maintaining bone health and preventing osteoporosis. While dietary sources like dairy, leafy greens, and fortified foods should be the primary focus, supplements can help fill any nutritional gaps. It is equally important to ensure adequate vitamin D intake and to engage in regular weight-bearing exercise to maximize calcium absorption and bone strength. By taking a balanced approach to nutrition and physical activity, older women can take significant steps to protect their skeletal health and overall quality of life. Always consult with a healthcare provider to determine the right course of action for your individual health needs.
