Calcium confusion? 5 things to know
When’s the last time you stopped to think about how much calcium you’re getting and whether it’s the right amount?
These questions matter because calcium plays such an important role in our bone health, as well as our nerve and muscle function.
The body doesn’t make calcium, so every bit we get has to come through what we consume. If we don’t take enough in, we do damage to our bones, experts say.
“If we’re not eating enough calcium to provide our bodies with the calcium that we need, then our bodies will take it from our bones,” said Colleen Garber, RDN, a dietitian with Spectrum Health Pennock.
These are their Top 5 tips about calcium:
1. Do the math
Dr. Hamblin said her typical patients—women older than 50—need 1,200 milligrams of calcium a day. To find out how much you need based on your age, sex and other factors, see the recommended amounts published by the Institute of Medicine.
Once you know how much you need, calculate how much you get from what you eat and drink. Calcium is found in milk, cheese, yogurt and other dairy products, vegetables such as kale and spinach, and calcium-fortified foods such as cereals, breads and fruit juices.
Here’s how to do the calculations:
- Read the Nutrition Facts label on food.
- Calcium is given as a percentage. This is the Percent Daily Value of calcium contained in one serving of the food, based on the recommended daily allowance for healthy adults. To convert this percentage into milligrams of calcium, simply add a zero. So if the label reads “Calcium 20%,” you’ll know that one serving provides 200 milligrams of calcium. (This trick works for calcium but not for all nutrients.)
- Garber’s rule of thumb is that foods with a Percent Daily Value of 20 percent or more are great calcium sources, while foods with 5 percent or less are not.
- For fresh leafy greens and other foods that don’t always come with a Nutrition Facts label, see the National Osteoporosis Foundation’s chart, “A Guide to Calcium-Rich Foods.”
If your total calcium intake matches your recommended allowance, you’re good to go. If you fall short of the target, you should add a calcium supplement.
But don’t overdo it. With calcium, as with most nutrients, it’s possible to get too much of a good thing. Kidney stones and coronary disease can result from getting too much calcium, Dr. Hamblin said.
2. Think ‘food first’
Though calcium supplements are valuable for filling in the gaps in your diet, the best way to get calcium is through food.
“My biggest push with my patients is I always tell them to think ‘food first,’” Garber said. “Your (best) nutrition is always going to be packed on your plate and not in a pill.”
Food is the best source because the calcium in food comes bundled with other things—vitamins, minerals, fiber—that work together to maintain your health in the way that a pill alone can’t, Garber said.
3. Use supplements wisely
The gut can absorb only 500 to 600 milligrams of calcium at a time, Dr. Hamblin said, so don’t bother with a 1,000-milligram tablet. For the same reason, don’t take your calcium supplement with a glass of milk. Doubling up like this gives the body more than it can absorb at once.
Try to spread out your calcium intake over the course of the day.
Choosing supplements can be tricky, but understanding what to look for makes it easier. Two main kinds of calcium are sold in pill form, Garber said:
- Calcium carbonate—This type tends to be more economical and has a higher percentage of elemental calcium per tablet. It’s a good choice for people who don’t use antacids. Calcium carbonate supplements should be taken with food, because eating produces gastric acids, which help dissolve the supplement so the body can absorb the calcium.
- Calcium citrate—This is the best form of calcium for people who take acid-blocking medicines like Zantac, Pepcid or Prilosec. Calcium citrate is easier to digest than calcium carbonate. It can be taken with or without food.
4. Pair calcium with vitamin D
Even if you get the right amount of calcium, your body won’t be able to absorb it without the right amount of vitamin D. And getting vitamin D can be difficult, especially during a Michigan winter, because its main source is the sun.
“How your skin reacts to the sun depends on your age, the color of your skin and how long you’re out in the sun,” Garber said. “Older people tend to cover up more in the summer, so they’re not getting that exposure to the sun.”
As a result, she said, many people today are vitamin D deficient.
In addition to seeking out foods containing vitamin D, people can take vitamin D supplements. Check the label on your calcium supplement, though, because many calcium supplements have vitamin D added.
5. Avoid bad combinations
Getting our calcium intake right also requires us to avoid certain combinations and excesses. Garber suggests we follow these pointers:
- Ask your doctor or pharmacist about your combination of medicines. Calcium can interfere with certain drugs, including tetracycline antibiotics and some thyroid hormones.
- Don’t take a calcium supplement or eat calcium-rich foods at the same time as an iron supplement. Experts believe calcium interferes with iron absorption, so take them separately.
- Avoid excessive caffeine. Drinking three or more cups of coffee a day can accelerate the loss of calcium through urine. Drinking a lot of tea and cola can have the same effect.
- Avoid heavy drinking. Excessive alcohol consumption can hinder the body’s ability to absorb calcium, leading to bone loss.