A strong skeleton is important as we age because it helps us stand upright and prevents osteoporosis and fractures. Unfortunately, nearly one in two adults aged 50 and over have low bone mass, which is a risk factor for osteoporosis.
It’s no secret that diet is one of the best ways to protect your bones, but getting enough calcium isn’t enough. In fact, taking calcium supplements without getting enough vitamin D may not be very effective. Read on to learn more about the roles of calcium and vitamin D in the body and how they work together to support your health.
Why do you need calcium?
You probably know that calcium is important for strong bones, but calcium has many other functions for the body. The main functions of calcium are:
- Give structure to bones and teeth
- Promote tissue health for normal body movements
- Regulate blood vessel contraction (for cardiovascular health)
- Promote muscle function
- Promotes blood clotting
- Facilitate nervous system signaling
- Regulation of hormone secretion
How much you need
Recommended dietary allowances (RDAs) for calcium are primarily based on age. For adults aged 51 to 70, they also vary by gender. Daily recommendations for total calcium from food and supplements are as follows:
- 0–6 months: 200 milligrams
- 7 to 12 months: 260 mg
- 1 to 3 years: 700 mg
- 4 to 8 years: 1,000 mg
- 9 to 13 years: 1,300 mg
- 14-18 years: 1,300 mg
- 19–50 years: 1,000 mg
- 51–70 years: 1,000 mg for men, 1,300 mg for women
- 71 years and older: 1,200 mg
Why You Need Vitamin D
Vitamin D plays many roles in the normal functioning of the body. Spoiler alert: One of them works in tandem with calcium to promote bone health. Here are the main reasons why you need vitamin D:
- Absorption of calcium in the intestine
- Maintaining normal blood calcium and phosphate levels
- Promote bone health
- Reduce inflammation
- Metabolize glucose
- Cellular health
- Immune function
How much you need
As with calcium, recommended daily intakes for vitamin D vary by age and are based on total intake from supplements and food sources. They are as follows:
- 0–12 months: 400 international units
- 1–70 years: 600 IU
- 71+ years: 800 IU
Of course, getting some sun is one of the best ways to get vitamin D, but overexposure to the sun carries real risks. These dietary recommendations are for people with limited sun exposure.
What is the connection between vitamin D and calcium?
Vitamin D and calcium are both essential for overall health and well-being. In fact, one of vitamin D’s primary roles is to aid in calcium absorption. “Vitamin D acts like a key, unlocking the door for calcium absorption in the intestines,” says Dr. Taher Saifullah, founder of the Spine and Pain Institute in Los Angeles.
“Without adequate vitamin D, calcium absorption drops, which impedes bone mineralization and can lead to problems like osteoporosis,” says Dr. Saifullah. It could even lead to calcium deficiency, adds Dr. Soma Mandal, a board-certified internist at Summit Health in New Providence, New Jersey.
So, should you take vitamin D and calcium together?
Experts say yes to the question of whether calcium and vitamin D should be taken together. “This combination is often recommended to prevent or treat osteoporosis and other diseases related to bone loss,” Mandal says.
Research supports these claims. A meta-analysis of six studies found that taking vitamin D and calcium supplements together reduced the risk of bone fracture by 6% and the risk of hip fracture by 16% in older adults. The combination was much more effective at reducing fracture risk. Taking vitamin D alone was not protective.
Another study found that, in postmenopausal women in particular, combined calcium and vitamin D supplementation significantly reduced the incidence of hip fractures. “This combination is especially important for older people and those who don’t get enough sun or have specific health issues,” says Saifullah.
That said, not everyone needs to take these supplements. If you eat enough calcium- and vitamin D-rich foods, such as fortified dairy products, fatty fish, and eggs, and you’re not at risk for deficiency, you probably don’t need supplements. In fact, research suggests that calcium- and vitamin D-fortified dairy products may help improve overall bone mineral density in postmenopausal women better than supplements. It appears that dairy products may boost the effect of these two nutrients on bones.
Side effects and potential risks
Taking vitamin D and calcium is generally safe. However, there are some risks worth considering.
For one thing, calcium supplements can cause gastrointestinal symptoms like constipation, gas, and bloating, Mandal says. Plus, too much calcium can increase your risk of kidney stones, especially if you’re not properly hydrated, Saifullah adds. The safe upper limit for calcium is 2,500 mg (or 2,000 mg if you’re 51 or older), an amount unlikely to cause side effects.
Some studies have also shown that calcium supplementation may increase cardiovascular risk, although the results are mixed and the link is currently controversial. “In rare cases, excessive consumption of these supplements can lead to hypercalcemia (high levels of calcium in the blood), which can cause symptoms such as nausea, vomiting, confusion and abnormal heart rhythms,” says Mandal.
Additionally, these supplements may interact with certain medications, including statins, steroids, thiazide diuretics, levothyroxine, lithium, quinolone antibiotics, and dolutegravir.,If you buy a calcium supplement at the pharmacy, you may want to stop and ask the pharmacist if it might interact with any medications you are currently taking.
How to Take Your Vitamin D and Calcium Supplements
Dosage
Recommended daily intakes for adults range from 600 to 800 IU of vitamin D and 1,000 to 1,300 mg of calcium. One study found a reduction in fracture risk with 400 to 800 IU of vitamin D and 1,000 to 1,200 mg of calcium per day in older adults.
That being said, supplementation should fill in the gaps in your diet and address any specific needs you may have based on nutritional deficiencies or health issues. So, if you eat plenty of calcium-rich foods and get plenty of sun exposure, you may not need to take many supplements, if any at all.
Talk to your healthcare provider for personalized recommendations based on your diet, health conditions, medication and supplement regimen, and nutritional needs.
Hourly
“Take vitamin D with meals containing healthy fats for better absorption. For calcium, it’s often best to spread doses throughout the day, taking no more than 500 to 600 mg at a time,” advises Saifullah. If you’re taking a combination calcium and vitamin D supplement, check the dose and talk to a healthcare professional to determine if you should split the dose or take it all at once.
Other factors to consider
If you’re not sure whether you need a supplement, your doctor can do a blood test to check your vitamin D levels. A registered dietitian can also help you assess your dietary intake of each nutrient to see if you’re meeting your daily needs through food alone. They may also want to monitor your levels periodically to make sure they’re healthy, Saifullah says.
Additionally, when selecting a supplement, make sure to purchase one from a reputable manufacturer that has been third-party tested for purity and potency, as the FDA does not verify these factors before a supplement is sold.
The essential
There’s no doubt that both calcium and vitamin D are necessary for optimal health, especially bone health. Taking them together has been proven to be more effective than taking them alone, but there are still potential side effects, especially if you take too high a dose. Talk to your healthcare professional before starting a new supplement to get advice on safety and the right dosage for you.