Calcium helps bone and heart health, while zinc boosts the immune system and magnesium improves circulation and nerve function. Large bottles holds 250 capsules; lasts for two months. Good value.
Capsules are larger. Recommended to take four daily.
Contains 630 milligrams of calcium and 400 IU of vitamin D3. Gets high marks for fast absorption. Made of pure, quality ingredients with no artificial additives, soy, gluten, and more. Suitable for vegetarians.
Tablets are very large and difficult to swallow, so some customers resorted to dissolving them in beverages.
Supplement is 100% vegetarian. Includes calcium and other minerals that support bone strength, joint flexibility, and heart health. Sold in easy-to-swallow slim tablets that provide a slow, steady release. Does not contain any animal byproducts, dairy products, or synthetic binders.
Sometimes causes nausea and fatigue after initial use. Tablets are very small.
Calcium supplement includes magnesium and vitamins D and K. Made from pure fruit. Free from wheat, gluten, egg, dairy, and synthetics. Easy to swallow. From a trusted name in supplements.
High price. Need to take three daily with meals.
Gluten-free, vegan, non-GMO supplements that are easy to take and fast-acting. Manufactured by a trusted brand. Can be taken with meals. Each bottle can last up to three months.
Taking two capsules once a day may be tolerable, but taking two-to-three times a day can be tedious.
We recommend these products based on an intensive research process that's designed to cut through the noise and find the top products in this space. Guided by experts, we spend hours looking into the factors that matter, to bring you these selections.
You probably already know you need calcium for strong, healthy bones. The question is, are you getting enough of it in your diet? Calcium supplements have almost become trendy among health enthusiasts, but not all calcium supplements are of equal value to your health.
It can be confusing when you see all the calcium supplements on the market. Some advertise bone meal or algae sources, but which one is right for you? If you’re unsure where to begin, you’ve come to the right place.
At BestReviews, our mission is to bring you the information you need to make smart purchasing decisions. We’ve put together this shopping guide to help you find your way to better bone health.
Calcium carbonate is one of the most common and least expensive forms of calcium. It can be found in eggshells, snails, limestone, and other rocks. It’s made of 35% to 40% elemental calcium, giving it the highest calcium concentration of all the forms. However, it has a relatively low bioavailability, which means the stomach has to make extra acid in order to absorb. Consequently, the side effects can include gas, bloating, and constipation. Drinking plenty of water and taking a calcium carbonate supplement with food can prevent some of these side effects.
Calcium citrate is a common, inexpensive form of calcium. It contains 20% elemental calcium, making it a less efficient source of calcium than calcium carbonate. While it isn’t the best source, it’s easier on the stomach, making it a good alternative if calcium carbonate doesn’t work for you.
Calcium phosphate is the form of calcium found in bones and teeth. However, it isn’t as common in supplement form. There are several forms of calcium phosphate, including dicalcium and tricalcium phosphate and hydroxyapatite, made of about 39% elemental calcium. This form of calcium is usually recommended if you’re also phosphate deficient, a condition that can occur with diseases that interfere with the absorption of minerals.
Calcium gluconate isn’t as common in supplement form because of its low elemental calcium levels. It’s one of two forms given intravenously by physicians in more extreme cases of calcium deficiency.
Calcium lactate has better bioavailability than many of the other forms of calcium but less elemental calcium at only 13%. Essentially, it’s easier for the body to absorb, but you don’t get as much calcium with each dose, which means you’ll need to take more of it to get the amount found in other supplements. It’s a common food additive that firms, thickens, and enhances food flavors. When it’s found in supplement form, it tends to be more expensive.
Calcium orotateCalcium orotate is naturally found in most living organisms and can be an effective calcium supplement. It has better bioavailability than calcium carbonate, but it isn’t as common in calcium supplements because it’s more expensive to produce.
Risk of calcium deficiency: You might have low calcium if any of these apply to you.
Diet low in calcium and vitamin D
Diet high in protein or sodium (causes more loss of calcium than normal)
Crohn’s disease or inflammatory bowel disease that limits ability to absorb calcium
Your physician might also recommend a calcium supplement if you’re a pregnant or postmenopausal woman. Calcium for osteoporosis prevention is often recommended for women over 50 and men over 70.
Keep in mind that too much calcium can be dangerous, too. The average adult needs 1,000 mg per day, but it can vary based on your age and risk factors.
Amount of elemental calcium: Calcium can only be found in compound forms, which means it’s attached to other atoms. Elemental calcium is the amount of pure calcium in that compound. For example, calcium carbonate contains 40% pure (elemental) calcium. To get the most bang for your nutritional buck, look for a supplement with high levels of elemental calcium. Otherwise, you’ll have to take more doses of the supplement low in elemental calcium to get a dose equal to that found in a supplement high in elemental calcium.
It can be hard to identify exactly how much elemental calcium is in a supplement. Some manufacturers include it on their labels, but others don’t. You can look at the recommended daily allowance (RDA) and calculate how much calcium you’re actually getting. The average person needs 1,000 mg per day, so if a label reads 20% of the RDA, you’re getting 200 mg of elemental calcium per dose.
In some cases, you might choose a supplement with a lower level of elemental calcium. If, for example, calcium carbonate upsets your stomach, you might look for a supplement with calcium citrate instead. You won’t be getting as much calcium per pill, but it will be easier for your body to digest.
Depending on the form, you can expect to pay from less than $0.05 to $0.25 or more per pill for calcium supplements.
Inexpensive: Supplements using calcium carbonate and calcium citrate start at less than $0.05 per pill. The supplements might include additional nutrients like vitamin D or magnesium.
Mid-range: At $0.05 to $0.15 per pill, you’ll find calcium supplements with calcium carbonate, calcium phosphate, and calcium citrate. Some of these supplements contain several forms of calcium.
Expensive: Supplements that cost $0.15 to $0.25 per pill usually contain calcium carbonate, calcium citrate, and calcium phosphate. But at this price, you’re likely to find supplements with other nutrients like vitamin D, vitamin K, and/or magnesium. You’ll also start to see supplements advertised as organic, vegetarian, and vegan.
Premium: At over $0.25 per pill, there are many organic, vegan, and vegetarian options. These supplements derive their calcium from algae, such as seaweed.
Talk to your physician before taking a calcium supplement. You want to make you aren’t taking any OTC or prescription drugs that could affect or limit how much calcium you absorb. For example, the use of some antacids, laxatives, and steroids can prevent your body from absorbing calcium from a supplement.
The average adult needs 1,000 mg of calcium per day. Women over 50 and men over 70 might need as much as 1,200 mg per day. To calculate your supplement needs, estimate how much calcium you get from your diet, say 800 mg, and look for a supplement that fills in the gap. So, in this case, you’d need 200 to 400 mg of calcium in supplement form.
Q. What do I need to know about calcium and vitamin D?
A. Without vitamin D, your body can’t create the hormones necessary to absorb calcium from your diet. Your body will start to use the calcium already found in your bones, weakening your body.
Q. What about supplements made from algae? Are they healthier?
A. Calcium supplements derived from algae, such as seaweed, are advertised as organic, natural, vegan, and/or vegetarian. These supplements usually get their calcium from red mineral algae, which is only found in specific locations around the world. The algae absorbs calcium and other minerals throughout its lifetime. After the algae dies, the remains can be harvested and processed for the calcium carbonate. The difference between this source of calcium carbonate and other more direct forms is the additional minerals absorbed by the algae. Strontium, silica, and vanadium are only a few of the additional nutrients found in supplements derived from algae. The manufacturers claim this form of calcium is more natural and readily absorbed than other supplements. However, at this point, these claims are unsubstantiated.
Q. Why do I have to take two or three calcium supplements per day? And why can’t I take them at the same time?
A. The body can’t absorb much more than 500 mg of calcium at once. Therefore, to get a full 1,000 to 1,200 mg per day, you might need take more than one supplement per day. The supplements will also need to be taken at different times to allow your body to absorb the nutrients.