Calcium is one of the most well-known but misunderstood minerals. It is added to everything from cereal to orange juice, yet there is a lot of evidence that supplements are not effective and may even be harmful…
Calcium Supplements: The Problem
There are several supplements that I personally take daily, even when eating a very high-quality real food diet because it is difficult to get enough of these nutrients from our modern food supply.
Other vitamins and minerals (like calcium and sometimes folic acid and iodine) are actually over-abundant in our current food supply and may be harmful.
Calcium is naturally found in dairy products and is often added to dairy and dairy-substitutes. Calcium is also added to many processed foods, cereals, breads and juices. Many people also take calcium supplements, especially during pregnancy and post-menopause, but recent research calls this practice into question.
Like so many other nutrients, Calcium needs cofactors (other vitamins and minerals) to be absorbed. Without these, calcium supplements are not bioavailable and may be harmful.
A 2012 study published in the British Medical Journal showed that those who took calcium supplements had a 139% higher risk of heart attack, though this increased risk was not present when the same amount of calcium was consumed from whole food sources. (1)
Other studies have shown the same correlation:
- A 2010 meta-analysis showed that calcium supplementation increased the risk of stroke, heart attack and death from all causes (2)
- A study published in JAMA in 2013 showed that supplementation in excess of 1,000mg/day was associated with a 20% increase in risk of death from cardiovascular disease. (3)
- Other studies, like a recent one published in the American Journal of Clinical Nutrition showed that calcium supplementation increased risk of kidney stones and prostate cancer (4)
- Chris Kresser showed that this risk is even higher in women “Additionally, a recent Swedish study reported a 40% higher risk of death among women with high calcium intakes (1400 mg and above), and a 157% higher risk of death if those women were taking a 500 mg supplement daily, compared to women with moderate daily calcium intakes (600-1000 mg).” (5)
So why does it appear that calcium supplementation can increase the risk of heart related problems?
Two possible reasons…
- Researchers speculate that when supplemental calcium is taken, it cannot all be absorbed and the excess is left circulating in the blood, which can lead to calcification in the arteries, or is excreted in urine, which may lead to kidney stones. (Here are natural remedies for kidney stones.)
- It is very difficult for the body to absorb many forms of calcium, especially when they are taken alone, as it needs cofactors like Vitamin K2, Magnesium and Vitamin D to be properly utilized.
Calcium for Bone Health?
But, what about bone health? Turns out, calcium supplements aren’t the silver bullet for bone health either…
A 2012 study showed that supplemental calcium (above the recommended amount from food) did not increase bone density or reduce fracture rate. (6)
In fact, in 2013, the United States Preventative Services Task Force reviewed 135 studies on calcium and rate of fractures and recommended that post-menopausal women STOP taking supplemental calcium. (7)
Food sources of calcium (like dairy, bone-in meats and certain types of fish) were shown to be beneficial for bone health without the increased risk of cardiovascular and other problems.
Dairy is the most recommended dietary source, but there are some confounding factors. Numerous studies in several countries have shown that dairy consumption reduced the risk of osteoporosis, hypertension and other problems associated with these diseases. (8,9,10)
Some in the natural health community claim that dairy is actually bad for bones because dairy products acidify the body, causing it to pull calcium from the bones to re-alkalize.
Chris Kresser thoroughly explained (and debunked) this theory, and a 2011 study reviewed this theory and found no scientific evidence to substantiate it. (11)
A Better Option: Food Sources of Calcium
The available literature points to the same conclusion that many of us feel intuitively- that food sources are better than supplements whenever possible and this is especially true with calcium.
Dairy is a controversial topic, since many people do not tolerate it or choose not to consume it. Fortunately, while it is the most well-known dietary source of calcium, it is by no means the only source and others may be better. Also, research suggests that the most beneficial part of dairy (especially raw dairy) for bone health may be Vitamin K2, not calcium. More on that below…
Wonderful non-dairy sources of calcium include:
- Sardines (canned)
- Salmon, with bones (canned)
- Leafy Greens
- Blackstrap Molasses
The Importance of Cofactors
Cofactors are also vital for proper calcium absorption and use in the body. In isolation, calcium (and many nutrients) can be harmful, as I explained above, but it is vital and helpful when consumed in proper balance with its cofactors.
There is an excellent book called Vitamin K2 and the Calcium Paradox, which explains in depth how Vitamin K2 is needed for proper utilization of calcium and how calcium consumption without K2 can lead to health problems.
K2 is found in raw dairy from pastured cows, liver, aged cheeses and natto (a fermented soy product). It is also available in supplement form.
Other cofactors for calcium include Vitamin D and Magnesium (among others). In fact, K2, Calcium, Magnesium and D3 are all better utilized when consumed together.
Personally, I prefer to get my Vitamin D from the sun whenever possible and my calcium from food, but I take supplemental forms of Vitamin K2 and use transdermal magnesium to keep my levels in optimal ranges. (This is a great quiz to see if you are deficient in magnesium).
Supplemental calcium is not the panacea for strong bones that it is made out to be. Calcium is certainly important, but it is most beneficial when it comes from food sources and when taken in proper ratio with its cofactors.
Do you take calcium supplements?
Discussion (52 Comments)
I think it is great that you personally get your vitamin D from the sun. For so many years I thought that was definitely the best source possible, but I found out recently that I am really deficient and read an article (which I can’t find), that the sun alone is not enough for most people. I just found this interesting, since I live in one of the sunniest places and am still deficient. I know there are a lot of factors that play into this, but I think everyone should talk to their Doctor about getting tested for Vitamin D levels regardless of how much sun they get.
On my gynocolgist’s recommendation, I took calcium supplements for 3 years, even though I get lots of calcium in my diet and also lift heavy weights. The kidney stones last August more than convinced me to stop those supplements.
Looking back, I should have insisted on a bone density scan before accepting her recommendation. As the scan showed, my bones are just fine and will continue to be just fine as long as I get calcium in my food and lift weights.
Strongly recommend you question your medical practioners’ habit of recommending various supplements (or even prescriptions), if they didn’t do any tests first that show you actually need it. Had I done so, I would not have gone through some very serious pain.
Ok so I take calcium 50th daily but I also take magnesium and vitamin D3. I don’t eat a lot of dairy nor do I eat fish or many other things with the bone in. Should I continue to take the calcium or find another way to get what my body needs. I originally started taking it because I didn’t want my teeth to rot out from having babies.
I have heard about the downside of taking calcium supplements before. (not from my doctor for sure). I am wondering, I suffer from bouts of Vertigo. My doctor told me I have calcium deposits near my inner ear and have to wait for them to dislodge on their own and through certain exercises. Is this due to calcium in my body being stored in the wrong place? Also, aren’t those little hard bumps that people get on their faces calcium deposits? I don’t take calcium supplements on a regular basis.
Great post. Interestingly, the bioavailability of calcium in brassica vegetables is higher than that in dairy products – 61% of calcium found in broccoli is absorbable, compared with only 32% of that in milk. The reason remains unknown. Only 30–40 per cent of the calcium present in other food and drinks is absorbed. Some types of dietary fibre (phytates from wheat in unleavened bread e.g. chapatti) also bind calcium in the bowel to form an insoluble, non-absorbable salt. High-fibre diets, which speed the passage of food through the bowels, will also reduce the amount of calcium absorbed. I do prescribed calcium PLUS vit D for patients with osteoporosis.
I was going to take a calcium/magnesium supplement with this next pregnancy to hopefully minimize my chances of getting pre-ecclampsia. I was borderline towards the end with my first one. I have rheumatoid arthritis and was told I have a higher chance of developing it with that. My rheumatoid arthritis has gotten a lot worse since my first. What are your thoughts on that?
Dairy is not a good source of calcium. there is not enough magnesium in dairy and also too much protein in dairy. greens are the best source of calcium without any side effects unlike dairy. just add them to your salads as well as steam them with your veggies. also concentrate on potassium, magnesium, silica, vitamin D as calcium is not the end all in bone health and management
Figs are also good source of calcium, I think best way to get it in babys diet. Hepls with constipation as well ???
Yes 🙁 Yes I take Calcium. I was told to since I breastfeed and since I’m lactose intolerant. This is my 3rd child and I’ve taken supplements while nursing child #2 and #3. I take Calcium 600 mg with vit D 400 IU…ugh…now I feel I need to stop. Which is better to know now than later. Unfortunately, I just started my 10 year old on a suppliment a couple months ago…Calcium & Magnesium with vit D and Zinc since I did a lot of reading on OCD (which he was labeled with 3 years ago) and I kept reading how ppl with this anxiety disorder are low in these areas. Here it is…I’m trying…making own lotion, body wash, laundry, detergent, clearing out the plastic…weekly (daily) baby steps to a healthier, safer life style…it feels great! On the other hand…reading this post was insightful and VERY important…just tugs at my heart a bit…I took my calcium because of my doc…I gave my son his because of my reading and want to do everything in my power to help him conquer his anxiety disorder. Kinda feel like a mouse on a treadmill right now after reading this. 2 steps forward, 1 step back. Okay…I guess here’s to throwing out the supplements. I will say I understand receiving the nutrients from food itself is best…Thanks for the post…
You might also want to look into magnesium (Mg). I was an RN for 40 years and learned more about Mg after I retired. As a Home Health nurse I taught my diabetics to take Mg to control their sugar; my wound patients to use it to help heal. That was about all I knew about it. I was put on Mg for seizure control. My seizures were not frequent, but every epilepsy med caused such side effects that I finally refused to take any more. My neurologist already had be on B complex and suggested adding magnesium.
The Mg benefits surprised me. I started studying up on it. It is needed for every one of our body functions. The 2nd thing that I learned was that a serum blood level will not give you a true Mg level. Mg is constantly circulating, so even at low amounts, it looks adequate. A cellular count needs to be done. If your potassium is low, chances are good your Mg is also. It is recommended for kids with ADD, ADHD, OCD and so on.
Water used to be our best source of Mg. The fluoride added (not the natural fluoride normally found in food or water) binds with the Mg making it useless. The same thing happens with plants. Mg is decreased by all the additives and preservatives. I’ve been on Mg along with my other routine supplements for 10 months. I am sleeping better, don’t feel as skittish, and the fibro pain is gone. Still have the ringing in my ears and forgetfulness, but skin looks better and my balance is better. There’s much more, but not enough space here. From my research, I do not believe the RDA levels are adequate. Each of us is different–one may need 1000mg a day, yet another could get by with 500mg extra.
Mg helps calcium be absorbed better and their are differences in calcium and magnesium. OTC supplements do not have any laws controlling them; therefore, they do not necessarily have in the pill what is on the label. That was another amazing fact which I thought was absurd. My patients used Nature Made so that’s what I bought the first time. I’ve tried several others, but Nature Made seems to be the best so far. I buy Mg and K+ I need OTC and use Nutrilite for all my supplement needs. They are organic and trustworthy. They have a line for children, but you still need to talk to his pediatrician. That was my last surprise–both my GP and neurologist have recommended various supplements for me to take. Most doctors don’t know any more about vitamins than the man in the moon. ConsumerLabs.com is a good place to check if you want to know about the quality of a vitamin brand. They do charge a membership fee. Back when you could check for free, Nutrilite was #1 or 2.
Remember also, if the med directions tell you not to take with milk, you need to take the calcium supplement at a different time.
What do you give a toddler in substitution for dairy milk? Doctors always recommend homo milk starting at 12 months, and my little guy is now 20 months and I have been so conflicted about giving him so much dairy. I personally don’t consume it. I have been giving him almond milk lately (without carrageenan), and am hoping that this is an appropriate substitute for homo milk.
I had the same feelings with dairy and my kids. I give them organic hemp milk it’s so easy to make just hemp hearts and water. You don’t need to strain or soak them either. My kids love hemp milk over all other seed or nut milks. I also give them lots of fruit and veggies, raw organic cheese from a local dairy, eggs, and bone broth. I’m pretty sure they get enough nutrition and processed dairy milk has been processed in a way that really there is no nutrition left. The enzymes are dead and gone and it’s super sugary which isn’t good either. Follow your gut literally lol. Sounds like you’re on the right path!