Calcium from the periodic table with a bunch of calcium supplements surrounding it and a text bubble saying supplements for optimal bone health

What Supplement Regimen Do I Need for Optimal Bone Health?

The major players in the supplement world for bone health are calcium, magnesium and vitamin D. This article discusses how and when to take these supplements, along with other micronutrients important for bone health.


Many people think of calcium first when talking about bones. It’s true that 99% of calcium is in our bones and teeth, but it’s not necessary for everyone to be supplementing calcium. Over the past few decades, the number of people taking calcium supplements has risen drastically. However caution must be exercised when taking calcium. There is a rising body of evidence on the adverse effects of calcium on non-skeletal health, especially cardiovascular health [1]. First let’s talk about calcium requirements.

Calcium Requirements

Before discussing what supplements you need, it’s important to know how much calcium you need. These are the daily recommended intake of calcium for various age groups. Please note the totals are total elemental calcium obtained through supplements and food.

The Institute of Medicine’s guidelines are as follows [1]:

  • Children
    • 1-3 years: 700 mg/day
    • 4-8 years: 1000 mg/day
    • 9-18 years: 1300 mg/day
  • Men
    • 18-70 years: 1000 mg/day
    • 70+ years: 1200 mg/day
  • Women
    • 18-50 years: 1000 mg/day
    • 51+ years: 1200 mg
  • Pregnancy/Lactating
    • 14-18 years: 1300 mg/day
    • 19-50: 1000 mg/day

Osteoporosis: demands for calcium actually remain the same. The issue with osteoporosis is that bone is breaking down faster than it can be built up. There is generally enough calcium present.  Several trials have been conducted, in which they investigate the effect of taking calcium versus taking supplemental estrogen (in menopausal women), and it has been determined that it is actually estrogen that increases bone mass [2]. Furthermore, it’s known that vitamin D insufficiency has a closer association to fracture risk than calcium deficiency. These are the reasons the requirements for calcium are not increased for an osteoporotic woman. Although calcium is very important in osteoporosis, we don’t need higher amounts; the goal remains the same – to increase bone mass.

Don’t Supplement Calcium Alone.

There appears to be a difference between supplemental calcium and dietary calcium. Research has shown that high dietary calcium is safer than loading with calcium supplements [1]. There is now an emerging trend in the scientific literature: high calcium supplementation is associated with increased cardiovascular risk [1]. The studies show a link between supplemental calcium intake and artery calcification. Taking too much calcium is leading to calcium deposition within the walls of blood vessels. There are studies showing a link between high supplemental calcium intake and increased risk of myocardial infarction, stroke, cardiovascular mortality and kidney stones [1]. I want to re-iterate – high supplemental calcium is dangerous, but dietary calcium is fine.  Other research has shown that the highest total dietary calcium (1453 mg or more) compared to low (<434 mg) had 27% lower risk of atherosclerosis – proving dietary calcium is actually protective of atherosclerosis. This study was very high quality – it was based on 5448 adults, with no prior cardiovascular disease [3]. For more information about the dangers of taking calcium alone, please click here. 

Take home message about Calcium

Look at the table above and try to get your recommended calcium intake through diet alone. If you still find you’re below the recommended intake, consider calcium supplementation. I recommend not to take calcium by itself; combine it with these other important vitamins and minerals discussed below.

Vitamin D

Vitamin D is popular but not everyone realizes how important it is for bone health. We do make it from cholesterol when we expose our skin to sun, but we can also choose to supplement it.

Vitamin D Requirements

It should be noted, various resources will state different optimal ranges of serum Vitamin D. This is based on different research. Even when you go for Vitamin D serum testing, ‘normal’ reference ranges will differ from lab to lab.

The US Institute of Health recommends serum Vitamin D to be between 50-60 nmol/L. The upper limit is about 100 nmol/L [4]. Vitamin D supplementation is recommended when a person can’t get their serum levels up through sunlight. There are small amounts in food, but the major contributing sources are sunlight and supplements.

Vitamin D supplementation alone

Vitamin D is supplemented for many reasons. However, there is some controversy as to whether it is effective when taken alone in optimizing bone health [4]. A lot of doctors and news outlets are reporting that Vitamin D by itself is useless for bone health and minimizing fracture risk. A Cochrane Review was conducted in 2014 and they concluded that “vitamin D alone is unlikely to prevent fractures in…older people” [5]. The main limitation of the review was that none of the studies they assessed tested vitamin D above 800 IU. As you may know, the typical dose of Vitamin D supplements is 1000 IU [4]. So, the Cochrane review was looking at a low dose of Vitamin D, when it is usually prescribed at significantly higher doses – some people take 3000-4000 IU per day to have impacts on their blood levels. The authors of the review even stated that a higher dose of Vitamin D would be necessary to raise serum (blood) levels of Vitamin D [5]. To see the Cochrane article, click here.

So should you take Vitamin D by itself if you’re getting enough Calcium?

I generally test my patients’ serum Vitamin D levels, and if they are lower than the recommended levels, I will supplement vitamin D (alone) if calcium is obtained adequately through diet.

Vitamin D and Calcium Co-Supplementation

If you aren’t getting enough calcium in your diet, take calcium supplements but be sure to take it with Vitamin D. Studies have shown that Vitamin D given with calcium elicits a small reduction in fracture risk and death [6], as well as improving bone mineral density and reducing fall risk [7]. Later we will also discuss magnesium, and I would include magnesium whenever taking calcium too.

Vitamin D Safety

Intake of vitamin D above current dietary reference ranges has not been associated with increased risk or adverse effects. It should be noted there is limited research on very high doses of Vitamin D taken long term [7]. It is important to supplement with the intention of keeping serum levels between 50-60 nmol/L [4]. Some people also prefer taking a mega-dose of vitamin D once in a while rather than daily, which is also safe and effective [4]. One study looked at people over 65 years old taking 100 000 IU of vitamin D3 every 4 months without calcium, and it was shown to reduce overall fracture rate by 33% (over a 5 year span) [4].

How to Supplement Vitamin D

Remember the goal of supplementation is to keep serum levels between 50 and 60 nmol/L [4]. No matter how low or high your dose, you’re goal is to get to this range.

The confusing thing with vitamin D is there are many factors that affect its absorption thereby making serum concentrations variable among individuals taking the same supplemental dose [4].

These factors all affect how much Vitamin D you'll get:

  • Age
  • Race/ethnicity: darker skin requires about 3-6 times more UVB exposure to get the same effective dose of vitamin D
  • Body composition (obesity)
  • Renal function
  • Geographic functions
  • Sex
  • Calcium/phosphorus status
  • Genetics
  • Estrogen use
  • Supplement use of D2 or D3

As you can imagine, it’s very difficult for me to tell you how much to supplement without having met you. I recommend finding a Naturopath or like-minded doctor to get Vitamin D tested and supplement according to their recommendation. To give you a rough idea of how one may treat vitamin D deficiency, I’ll give you an example. If someone's serum vitamin D is low (about 30 nmol/L) a loading dose can be used to raise levels quickly, with a maintenance dose to follow [4]. A typical loading dose would be about 3000-5000 IU per day until you hit 50 to 60 nmol/L; we usually re-test after 3 months. Once levels are in the adequate range, a maintenance dose can be taken at a dose of about 1000-2000 IU a day [4].

Vitamin K2

Over the last few years, vitamin K2 has been getting a lot of attention. It’s in most ‘bone support’ supplements, and often found in Vitamin D supplements. Let’s see what it’s all about.

How Vitamin K2 works

For bone health, Vitamin K2 is very important. It regulates calcium metabolism by activating a protein called matrix GLA protein (MGP). MGP has one main purpose: to inhibit vascular mineralization and encourage bone mineralization and organization [8]. Essentially, Vitamin K2 helps the body inhibit and clean up calcium build up in the arteries, allowing the arteries to stay flexible and healthy. Remember, high supplemental calcium leads to calcified arteries, which leads to cardiovascular complications.

Do I have to take Vitamin K2 if I take Calcium or Vitamin D?

Here’s where things get tricky. There is a lot of convincing evidence that Vitamin K2 helps with bone calcification and keeps the arteries from being calcified. I would agree if you take calcium a Vitamin K2 supplement would be of great benefit. However, a lot of supplement companies, health professionals, and online blogs claim that vitamin K2 MUST be taken if you’re supplementing Vitamin D.

Hypervitaminosis D is when we have too much Vitamin D. A lot of people are claiming that any amount of supplemental Vitamin D should be accompanied by Vitamin K2 [9]. The claim is that many people are taking excessive amounts of Vitamin D, and one of the ramifications of taking too much Vitamin D is increased calcium deposition in the bones. It is true that excessive amounts of Vitamin D does negatively impact Vitamin K2 dependent MGP (that we discussed above). The thing is, research has not been able to conclude at what dose of Vitamin D it starts behaving in toxic ways. In 1997, the Institute of Medicine and Health Canada published a report on dietary intakes of calcium, phosphorus, magnesium, Vitamin D and fluoride. In the report they stated that high levels of Vitamin D can cause increased serum calcium and eventual soft tissue deposition (including arteries) [10]. A lot of papers quote this study as a reason to take Vitamin K2 along with Vitamin D. The difficulty lies in the fact no one has been able to establish which dose of Vitamin D3 elicits this response in calcium. Although it's safe to take Vitamin K2 with Vitamin D3 supplements, it’s difficult to tell how high a dose this becomes a requirement. Some research has shown doses up to 4000 IU of Vitamin D3 has no calcium related adverse effects [11]. I personally us this as my cut off for patients. I am comfortable giving up to 4000IU per day before co-administering vitamin K2. I wouldn’t necessarily give this dose for long term use, but for a few months as a loading phase, I feel there is no necessity for K2.  There are currently no published human or animal trials on Vitamin D and Vitamin K pharmacology studies looking at their effects on calcium metabolism [12].


Of the 17 minerals considered essential – this is one of the most famous for stress and relaxation. It basically counteracts calcium [13]. Calcium is used in our muscles to contract; magnesium works to relax those same muscles. Its effect as a muscle relaxant is well known and well understood. Increasing magnesium intake has been credited with reducing risk of stroke, heart failure, diabetes, and all cause-mortality [14].

Magnesium in Bone Health

Magnesium directly affects calcium metabolism in our bodies. In fact, a magnesium deficiency directly contributes to osteoporosis, which has been demonstrated in many studies across numerous species, including humans [13]. Magnesium has three important roles to play in bone health. It directly affects the three master regulators for calcium homeostasis: parathyroid hormone, vitamin D and osteoclast function [13]. Magnesium deficiency will cause parathyroid hormone to leach calcium from bones, interfere with proper vitamin D activation and stimulate osteoclasts to break bones down [13]. Simply put, low magnesium leads to major trouble for bones.

What about the Calcium:Magnesium Ratio?

Looking at a lot of supplements, you’ll see a lot of Cal-Mag supplements either boast a 2:1 or 1:1 ratio of calcium to magnesium. The whole debate about this ratio stems from a 1989 paper from James Durlach. In this paper, he proposed a max ratio of 2:1 calcium to magnesium [15]. This means through diet and supplementation, Durlach said we should limit the amount of calcium to twice that of magnesium. A lot of people have misconstrued this statement and promoted formulas at a ratio of 2:1. The mistake is that most of the population is getting adequate amounts of calcium and low amounts of magnesium in their diets. In his 1989 paper, Durlach approximated 15-20% [15] of the population was already deficient in magnesium; that number is now approximated to be closer to 40% in Canada [16]. So now, with people taking 2:1 cal-mag supplements, getting a lot of calcium in their diets and being deficient in magnesium, many people are closer to the ratio of 5:1 or 6:1 calcium to magnesium.

Finally: Boron, Manganese, Zinc, and Copper

Last but not least, these trace minerals are also important for bone health. Typically, you’ll find these in bone formulas as they are important for enhancing calcium absorption, utilization, and supporting collagen production. These nutrients are typically not required to be taken as a stand-alone supplement; they’re usually incorporated into other formulas.


a pile of supplements used for bone health including magnesium, vitamin d3, boron, manganese, zinc, copper, vitamin k2, and calcium


Interested in learning more?

Read on in our series of articles on Bone Health!

About the Author - Dr. Johann de Chickera

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Dr. Johann is a fully licensed Naturopathic Doctor. His approach emphasizes the importance of living a healthy lifestyle and improving one’s health naturally. Dr. Johann obtained a Doctor of Naturopathy at the Canadian College of Naturopathic Medicine (CCNM). Education at CCNM is a vigorous four years, with a curriculum involving biomedical sciences, physical diagnosis, clinical nutrition, traditional Chinese medicine and acupuncture, botanical (herbal) medicine, physical medicine, homeopathy and lifestyle management.

While Dr. Johann has a general practice, he focuses on fertility, hormonal imbalances, gut health, and autoimmune disease.

To book in please call us at (519) 442-2206 or click here.

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