Calcium and Vitamin D: How much is enough? How much is too much?
Most people know that healthy bones need calcium, and many understand that vitamin D is needed for calcium absorption.
Calcium is also needed for our heart, muscles, and nerves to function properly. Lately, there's been a renewed interest in calcium and vitamin D, which brings up several questions. Are you getting enough? What are good sources of calcium and vitamin D? What are the consequences of calcium or vitamin D deficiencies? How much calcium and vitamin D do you need to be healthy? The answers can be highly individual and not always simple. Are you getting enough calcium and vitamin D?
According to national surveys, most Americans are getting enough vitamin D and calcium through diet and, in the case of vitamin D, through sunshine as well. However, some people may not be getting enough calcium and/or vitamin D and should increase their intake of foods rich in these nutrients and possibly take a supplement. For example, adolescent girls may not be receiving enough calcium, the elderly may not be receiving the necessary amounts of calcium and vitamin D, and people with dark skin pigmentation may be getting too little vitamin D.
What are the sources of calcium?
Calcium is a mineral found in many foods, including the following:
- Milk, yogurt, and cheese
- Kale, broccoli, and Chinese cabbage
- Canned sardines and salmon
- Most grains, such as breads and pastas
What are the sources of vitamin D?
Vitamin D is a fat-soluble vitamin that's produced when the sun's ultraviolet rays strike the skin and produces vitamin D. Unfortunately, it's naturally present in very few foods. Most of the vitamin D in our diet comes from foods such as milk, ready-to-eat breakfast cereals and orange juice that's been fortified with added vitamin D and calcium. Some of the best food sources of vitamin D include certain fish, such as salmon, tuna, and mackerel, and fish liver oils. Smaller amounts of vitamin D are found in cheese and egg yolks.
What about nutritional supplements?
Another source of calcium and vitamin D is nutritional supplements. There are several different calcium compounds from which to choose, such as calcium carbonate and calcium citrate. According to the US National Institutes of Health, calcium supplements are better absorbed when taken in small doses (500 mg or less) several times throughout the day. For many people, calcium supplements are better absorbed when taken with food. Check labels to ensure the supplement meets United States Pharmacopeia (USP) standards.
What are the consequences of calcium or vitamin D deficiencies?
Low calcium intake throughout life is associated with low bone mass and high fracture rates. Vitamin D insufficiency leads to rickets in children and osteomalacia in adults.
How much calcium and vitamin D do you need to be healthy?
Most Americans up to age 70 need no more than 600 international units (IUs) of vitamin D per day. Those 71 years and older may need as much as 800 IUs. The amount of calcium needed is based on age and ranges from 700 to 1,300 milligrams per day. These guidelines are detailed in Dietary Reference Intakes for Calcium and Vitamin D, a report from the Institute of Medicine (IOM), an independent, nonprofit organization that updates the nutritional reference values known as Dietary Reference Intakes (DRIs) for these interrelated nutrients (table).
| Dietary Reference Intakes for Calcium and Vitamin D | |||||||
|---|---|---|---|---|---|---|---|
| Calcium | Vitamin D | ||||||
| Life Stage Group | Estimated Average Requirement (mg/day) |
Recommended Dietary Allowance (mg/day) |
Upper Level Intake (mg/day) |
Estimated Average Requirement (IU/day) |
Recommended Dietary Allowance (IU/day) |
Upper Level Intake (IU/day) |
|
| Infants 0 to 6 months | * | * | 1,000 | ** | ** | 1,000 | |
| Infants 6 to 12 months | * | * | 1,500 | ** | ** | 1,500 | |
| 1–3 years old | 500 |
700 | 2,500 | 400 | 600 | 2,500 | |
| 4–8 years old | 800 | 1,000 | 2,500 | 400 | 600 | 3,000 | |
| 9–13 years old | 1,100 | 1,300 | 3,000 | 400 | 600 | 4,000 | |
| 14–18 years old | 1,100 | 1,300 | 3,000 | 400 | 600 | 4,000 | |
| 19–30 years old | 800 | 1,000 | 2,500 | 400 | 600 | 4,000 | |
| 31–50 years old | 800 | 1,000 | 2,500 | 400 | 600 | 4,000 | |
| 51–70 year old males | 800 | 1,200 | 2,000 | 400 | 600 | 4,000 | |
| 51–70 year old females | 1,000 | 1,200 | 2,000 | 400 | 600 | 4,000 | |
| >70 years old | 1,000 | 1,200 |
2,000 | 400 | 800 | 4,000 | |
| 14–18 years old, pregnant/lactating | 1,100 | 1,300 | 3,000 | 400 | 600 | 4,000 | |
| 19–50 years old, pregnant/lactating | 800 | 1,000 | 2,500 | 400 | 600 | 4,000 | |
| *For
Infants, Adequate Intake is 200 mg/day for 0 to 6 months of age
and 260 mg/day for 6 to 12 months of age. **For Infants, Adequate Intake is 400 IU/day for 0 to 6 months of age and 400 IU/day for 6 to 12 months of age. |
|||||||
| Institute of
Medicine of the National Academies |
|||||||
Can you take too much calcium and vitamin D?
Greater amounts of food fortification and rising supplement use have increased the chances that people consume high amounts of these nutrients. Getting too much calcium from dietary supplements has been associated with kidney stones, while excessive vitamin D can damage the kidneys and heart.
The best advice is to acknowledge that there's no one-size-fits-all answer and be aware of the issues surrounding these bone health nutrients. As always, work with your physician or pharmacist to achieve calcium and vitamin D levels appropriate for your individual health.
Useful References:
https://ods.od.nih.gov/factsheets/vitamind/
https://ods.od.nih.gov/factsheets/Calcium-QuickFacts/
https://iom.edu/Reports/2010/Dietary-Reference-Intakes-for-Calcium-and-Vitamin-D/Report-Brief.aspx
https://www.niams.nih.gov/Health_Info/bone/Bone_Health/Nutrition/default.asp
Table Source: https://www.nationalacademies.org/hmd/Reports/2010/Dietary-Reference-Intakes-for-Calcium-and-Vitamin-D/DRI-Values.aspx