Why calcium needs change after age 50
For women, the body's need for calcium increases significantly after the age of 50. This is primarily due to menopause, which leads to a decrease in estrogen production. Estrogen plays a vital role in regulating calcium absorption and bone formation, so the drop in its levels accelerates bone loss. On average, women can lose about 1% of their bone mineral density (BMD) per year during this period. This bone loss can accumulate over two decades, making older women, including those who are 70, particularly vulnerable to osteoporosis and fractures. Therefore, the recommended dietary allowance (RDA) for women 51 and older is higher than for younger adults.
The official recommendation: 1,200 mg daily
For a 70-year-old woman, the consensus from major health organizations, such as the National Institutes of Health (NIH) and the Office of Disease Prevention and Health Promotion, is 1,200 milligrams (mg) of calcium per day. This is the same recommendation for women aged 51 and over. This higher intake helps compensate for the lower efficiency of calcium absorption that often occurs with aging. It is important to remember that this is the total daily intake, which includes calcium from both dietary sources and supplements.
The crucial role of Vitamin D
Calcium is only part of the equation for strong bones. Your body needs vitamin D to properly absorb calcium from the food and supplements you consume. Without enough vitamin D, the body cannot effectively use the calcium you take in, forcing it to pull calcium from your bones, which weakens them over time. For adults over 70, the recommended daily intake of vitamin D is 800 International Units (IU), which is a slight increase from the 600 IU recommended for adults up to age 70.
Getting enough calcium from your diet
The best way to meet your daily calcium requirement is through food. A diet rich in calcium provides other essential nutrients that contribute to overall health. Here are some excellent dietary sources:
- Dairy Products: Low-fat milk, yogurt, and cheese are classic calcium powerhouses. An 8-ounce cup of low-fat yogurt contains over 400 mg of calcium.
- Leafy Greens: Certain green vegetables are great sources. Examples include kale, collard greens, and turnip greens.
- Fortified Foods: Many cereals, orange juice brands, and plant-based milks (like soy and almond milk) are fortified with extra calcium.
- Canned Fish: Canned sardines and salmon, specifically those with the bones, provide a significant amount of calcium.
- Tofu: If prepared with calcium sulfate, tofu is another excellent source for non-dairy eaters.
Understanding calcium supplements
For many 70-year-old women, meeting the 1,200 mg daily requirement from diet alone can be challenging. A supplement may be necessary, but it's important to choose wisely and use it correctly. Always consult a healthcare provider before starting any new supplement.
Comparison Table: Calcium Carbonate vs. Calcium Citrate
| Feature | Calcium Carbonate | Calcium Citrate |
|---|---|---|
| Elemental Calcium | 40% elemental calcium | 21% elemental calcium |
| Absorption | Best absorbed with food and stomach acid. | Better absorbed, can be taken with or without food. Recommended for those with low stomach acid. |
| Cost | Generally less expensive. | Often more expensive. |
| Pill Size | Can be larger, potentially requiring multiple pills. | Usually smaller, but may require more tablets for the same dose. |
| Best For | Individuals who can take it with meals. | Those with low stomach acid, older adults, or those on acid-reducing medication. |
Supplement best practices
To optimize absorption, it is best to take no more than 500-600 mg of calcium at one time. Splitting your daily dose into two or three smaller portions is recommended. For example, if you aim for 1,200 mg and get 600 mg from your diet, you could take two 300 mg supplements at different times of the day. Combining your calcium supplement with vitamin D can also enhance its effectiveness.
Potential risks of excessive calcium
While getting enough calcium is important, exceeding the upper limit can also be harmful. For adults over 51, the tolerable upper intake level (UL) is 2,000 mg per day. Consuming more than this, especially from supplements, has been linked to potential health concerns, including an increased risk of kidney stones and possibly heart-related issues. Therefore, it is critical to balance your intake from all sources to avoid overconsumption.
Conclusion
For a 70-year-old woman, the recommended daily calcium intake is 1,200 mg, supported by adequate vitamin D, to help maintain strong bones and prevent osteoporosis. This can be achieved through a diet rich in dairy, fortified foods, and leafy greens. When diet is insufficient, supplements can fill the gap. Women should choose the right supplement form for their needs and split the dose for optimal absorption. Most importantly, consult with a healthcare professional to create a personalized plan that balances dietary calcium, supplements, and vitamin D intake while staying below the safe upper limit.
