Did you know that vitamin D and calcium work together to benefit bone health? Meeting your recommended daily calcium intake and daily vitamin D requirement by age is crucial to keeping bones in optimal condition.
Keep reading for answers to common questions about calcium and vitamin D, including if you should take them together and osteoporosis guidelines.
What Is Calcium and Vitamin D?
Calcium is a mineral crucial to keeping the body healthy. While it is key to many processes in the body, calcium is important to (and known best for) maintaining bone health. A deficiency of calcium in the diet can cause the body to take stored calcium out of the bones, which can cause bones to be brittle, weak, and more prone to breakage.
Vitamin D also plays an important role in wellness, including bone, brain, and muscle health. It improves the body’s absorption of calcium to benefit bone health. Vitamin D also helps the body achieve homeostasis by helping balance the amount of calcium in the bloodstream.
Most people think of bones as static organs that don’t need much maintenance. However, bones are a type of living tissue that needs to be continuously nourished to be healthy. Getting adequate sources of calcium and vitamin D can be an important way to protect bone health, and promote overall wellness.
Sources of Calcium and Vitamin D
Surprisingly, many food sources of calcium and vitamin D overlap. If you struggle to get enough of these nutrients, fortified foods and supplements are also an option.
Generally, it’s recommended to try and get calcium from food sources first. Calcium is also best absorbed by eating various foods with calcium throughout the day.
Food options containing calcium include:
• Dairy: low-fat or fat-free milk, yogurt, or cheese
• Leafy green vegetables: broccoli, collard or turnip greens, kale, spinach, and Chinese cabbage (bok choy)
• Some breakfast beverages and foods: calcium-fortified 100% fruit juice, cereals, or rice drinks
• Some seafood: canned sardines or salmon with soft bones
• Some soy products: calcium-fortified soymilk or tofu, and soybeans
Calcium supplementation is also an optional “insurance plan” if you aren’t getting enough calcium from food alone. A doctor or dietitian may also recommend a calcium supplement, or calcium and vitamin D combo, if you are at risk for bone disease or your bone mass is measuring less than is desirable.
Popular forms of calcium found in fortified foods and supplements include:
• Calcium carbonate
• Calcium citrate or calcium citrate malate
• Calcium-containing multivitamins
Vitamin D Sources
As with calcium, getting vitamin D from food is recommended whenever possible. However, very few foods contain natural sources of vitamin D, so supplementation is often recommended.
The following foods are natural sources of vitamin D to include in your diet:
• Egg yolks
• Mushrooms grown under UV light
• Fatty fish, including salmon and trout
• Fortified beverages such as some soy milks, plant-based beverages, orange juices, and dairy
•Some organ meats like beef liver
The two major forms of vitamin D in foods and supplements are D2 (ergocalciferol) and D3 (cholecalciferol). If you’re searching for a vitamin D supplement, vitamin D3 is recommended. D3 is generally considered the most bioavailable, or suitable for absorption, in the body
Sunlight also plays a key role in vitamin D metabolism and absorption. Light from the sun triggers a chemical reaction in the skin that helps the body turn vitamin D into an absorbed form.
Risk of vitamin D deficiency increases when sun exposure is low, such as when daylight hours are shorter in the winter. Spending just 15 minutes a day in the sun can support your body in producing more vitamin D.
Vitamin D and Calcium Requirements
Interestingly, the body contains more calcium than any other mineral! Obtaining adequate amounts from food can benefit blood vessels, bones, and beyond. Since vitamin D works with calcium synergistically, obtaining enough of this vitamin is important, too.
Recommended Calcium Intake
The daily calcium requirement for adults ages 19-50 is 1,000 milligrams (mg). Since bone health is especially crucial for older adults to prevent falls and fractures, seniors need slightly more calcium daily at 1,200 mg. Remember that teenagers with growing bones need more calcium than others, with a daily recommendation of 1,300 mg.
Since calcium supplements vary widely, the amount of calcium in supplements is not standardized. Typically, calcium supplements contain 200-300 mg but may have more or less. Calcium-vitamin D combo supplements may contain more calcium, such as 500-600 mg.
Generally, it’s recommended to check a calcium supplement label closely and check with a healthcare professional before adding calcium supplements to your wellness regimen. When supplementing, don’t take more than 2,000-2,500 mg daily. Exceeding this amount may result in negative side effects that cause more harm than good.
Recommended Vitamin D Intake
Vitamin D recommendations come in the form of IU per day, or International Units. Commonly, a measure of micrograms (mcg) is also listed.
Typically, the amount of vitamin D you need each day increases with age as follows:
• Infants (0-12 months): 400 IU
• Toddlers to teens (1-18 years): 600 IU
• Adults (19-70 years): 600 IU, including individuals pregnant and lactating-
• Older adults (71+ years): 800 IU
Like calcium, vitamin D has a tolerable upper limit (UL), or a maximum amount. Ingesting more than this level may cause undesirable effects. For vitamin D, the UL is 4,000 IU. It’s nearly impossible to “overdose” on vitamin D through food, but you’ll want to double-check your supplement labels to ensure you aren’t accidentally taking too much.
Calcium and Vitamin D Recommendations for Osteoporosis
Individuals with osteoporosis, characterized by weak bones, are at especially high risk for calcium and vitamin D deficiency. To make matters worse, some medications may have side effects that interfere with nutrient absorption.
Fortunately, supplementation can make a big difference for high-risk individuals. Your dietitian or doctor may recommend a high-quality calcium and vitamin D supplement to prevent or manage osteoporosis.
In addition, a well-rounded diet complete with calcium-rich foods is recommended, along with daily weight-bearing exercise. Other minerals, such as potassium, magnesium, and phosphorus, are also needed to maintain bones properly.
Can You Take Calcium and Vitamin D Together?
Since calcium and vitamin D work together, they can generally be eaten or taken safely as supplements. As mentioned above, many foods containing calcium naturally have vitamin D, or commonly come fortified.
Eating these foods throughout the day can help meet your nutrient needs for bone health.
Calcium and Vitamin D Recommendations: Final Takeaways
Calcium and vitamin D really are a dynamic duo, working together to ensure the body’s bones support everyday activities. While obtaining most of your nutrients from food is recommended, sometimes supplementing with vitamins and minerals is needed to successfully prevent or manage disease.
Working with a dietitian or doctor can help you to identify how healthy your bones are, or what actions need to be taken to maintain healthy bones.
How we reviewed this article
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