Are You Meeting Your Daily Calcium Needs?
Did you know that calcium is the most abundant mineral in the body and accounts for around 2 pounds of an adult’s body weight? It’s common knowledge that calcium is an essential mineral for both health. Our bones are made up of a crystalline mineral compound called hydroxyapatite, composed mainly of calcium and phosphorus. In fact, about 99% of our body's calcium is stored in our bones, while the other 1% is located in the blood, muscle, and other tissues. Calcium is also vital to organ and musculoskeletal functioning. In order to keep our body functioning properly, we need a constant flow of calcium in the blood and tissues.
Essentially, our body gets calcium in two ways: from dietary sources and from our bones. When our blood calcium levels drop too low, parathyroid hormone is released, signaling the bones to release calcium into the bloodstream. Ideally, the calcium that is released from our bones is restored on a daily basis through calcium in the diet. Lack of calcium in the diet can result in bone loss and overall weakening of the bones.
How Much Calcium Do You Need?
Adults typically need around 1200 mg of calcium daily. If using a calcium supplement, it is recommended you take it with food in order to increase absorption. It is also suggested to spread the dose out over two meals; calcium levels tend to dip in the evening, so taking a dose at night can be helpful. When it comes to supplementation, there are several forms of calcium salts which are considered well absorbed, including: calcium carbonate, calcium citrate, calcium ascorbate, calcium glycinate, and calcium malate; it can be beneficial to look for supplements which contain a mix of these different forms.
Dr. Susan Brown, clinical nutritionist and bone expert, emphasizes that it is possible to take too much calcium; she recommends 600mg to 700mg if one chooses to supplement with calcium, and then to get the rest from one’s diet. Too much calcium is called hypercalcemia and can increase one’s risk for heart issues, kidney stones, prostate cancer, and constipation; the recommended upper limit of calcium intake from dietary supplements and food is 2,500 mg daily, or 2,000 mg daily if over 50.
Here are some calcium-rich food sources: seeds (chia seeds, sesame seeds, poppy seeds, and celery seeds), cheese, yogurt, leafy greens (kale, collards, and spinach), fish (anchovies, sardines, salmon, and cod), beans and lentils, whey protein, tofu, figs, milk and amaranth.
Other Micronutrients are Needed to Make Calcium Bioavailable
It’s important to note that dietary and supplemental intake of calcium alone is not enough to ensure you are meeting your daily calcium intake needs. Absorption and bioavailability of calcium is dependent on other key micronutrients; in other words, you could be getting high amounts of calcium, yet minimal mineral gain if these key micronutrients are lacking. These key micronutrients include magnesium, vitamin K2 and vitamin D.
Let’s take a look at the role these minerals play:
Magnesium: Magnesium is known to increase bone density and prevent osteoporosis. It is important to balance calcium with magnesium. While the recommended amount of magnesium is 300mg to 500mg daily, ideally one should aim for a 2:1 calcium-to-magnesium ratio. Magnesium rich foods include: legumes, nuts, darky leafy greens, buckwheat, rye, and seeds (such as pumpkin, sunflower, sesame, and brazil).
Vitamin K2: This vitamin plays a key role in the metabolism of calcium, as it activates the calcium-binding actions of two proteins, matrix GLA protein and osteocalcin, which are essential to helping build and maintain our bones. Vitamin K1 can partly convert to vitamin K2 in the body, and vitamin K2 is also synthesized by certain gut microbes. While there is not a current consensus on how much vitamin K2 is needed on a daily basis, it is recommended to get 90-120 mg of vitamin K1 daily. Many experts suggest aiming for between 10 to 45 mg of K2. Vitamin K2 rich foods include: high-fat dairy products from grass-fed cows, liver and organ meats, and fermented foods such as sauerkraut, kimchi, and miso. Many people lack adequate K2 in their diet, so if you don’t eat these foods regularly supplementation is a good idea.
Vitamin D: A lack of vitamin D alone can result in 65% less calcium absorption. This is due to the fact that inadequate levels of vitamin D result in a lower absorption of calcium in the intestines. Adults typically need 600 IU of vitamin D a day, with this amount increasing to 800 IU for adults over 70. If supplementing, it is recommended to choose vitamin D3 over vitamin D2 when possible. Aim to eat a variety of foods high in vitamin D, including: fish (look for low-mercury fish, such as salmon, sardines, anchovies, and cod), eggs (particularly the yolk), mushrooms, and fortified dairy products. It is also important to get daily sun exposure, as our bodies synthesize vitamin D from sunlight.
Are You Absorbing Enough Calcium?
One sign that you may not be absorbing calcium is if you experience leg cramps, particularly at night. Other potential signs of calcium deficiency include numbness or tingling in the fingers, abnormal heart rate and lack of appetite. Interestingly, it has been found that individuals can have a threefold difference in their calcium absorption rates. If you think you are lacking calcium, try increasing the amount of calcium-rich foods in your diet and supplement to meet your needs. As always, work with a qualified healthcare professional to address your unique health.