Calcium: Think you’re getting enough? Find out here
What is Calcium?
Calcium is the most abundant mineral in the human body and among the most important.
It constitutes 1.5-2% of our total body weight with 99% contained in our bones and teeth. The remaining 1% is in other tissues and circulation.
Benefits and Functions of Calcium:
Essential for the maintenance and development of healthy bones and teeth.
Weight loss: research shows that those supplementing with calcium achieve better weight-loss on a calorie restricted diet than diet alone
Cardiovasuclar health: shows efficacy in the treatment of high bloodpressure
Required for muscle contraction, blood vessel expansion and contraction, secretion of hormones and enzymes, and transmitting impulses throughout the nervous system
Chill out mineral: Can be calming to the nerves
Pregnant and nursing mothers: Calcium is often drained from the bones during pregnancy and nursing and becomes hard to replace in later years
Can be helpful in reducing leg cramps during pregnancy and alleviating fatigue and depression after delivery
PMS and Menstruation: powerful treatment for PMS! calcium plus magensium, vitamin D and B6 helps reduce menstrual cramps and symptoms associated with PMS
Calcium is absorbed in small intestines. However, not all calcium we consume will be absorbed.
Children absorb approximately 50-70% of calcium through dietary sources
Absorption decreases to 30-50% – and continues to decrease as people age to as little as 15% or even less!
The amount of calcium absorbed is dependent on a number of factors such as the acidic condition in our intestines, Vitamin D levels, magnesium, exercise, estrogen levels, protein, fat intake, age and quantity.
Factors that INCREASE Absorption:
Vitamin D is essential and required for calcium (and phosphorus) to be absorbed from the digestive tract.
Vitamin D also helps to maintain normal blood calcium levels – which is essential for cardiac function and bone health (see below).
Sunshine! Since UVB rays stimulate our own body to manufacture Vitamin D, taking calcium within the first couple of hours of sunbathing increases absorption and utilization
Exercise improves the circulation of calcium, increases absorption and improves bone density
Quantity – Less is More!:
The more calcium consumed at one time results in LESS calcium being absorbed! Absorption is highest in doses LESS than 500mg at one time. It’s best to spread out calcium intake though out the day
Factors that DECREASE Absorption:
Age: calcium absorption can be as high as 60% in childhood, and can decrease to as low as 15% in adulthood
Alcohol intake: alcohol intake can affect calcium status by reducing its absorption and by inhibiting enzymes in the liver that help convert vitamin D to its active form
Excess Salt intake: can lead to increased calcium loss in the urine
Caffeine intake: this stimulant in coffee and tea can modestly increase calcium excretion and reduce absorption
Foods High in Oxalic acids: (spinach, beet greens, chard, rhubarb); and Phytic acid (such as wholegrains) can reduce absorption; although the extent to which these compounds affect calcium absorption varies.
Iron: also inhibits the absorption of calcium
Even though most of the body’s calcium resides in the bones, blood and cellular calcium requirements need to be met first. Normal blood calcium levels are 10mg/100ml of blood. If this is not maintained through proper diet, the parathyroid hormone will draw calcium from our bones to meet our blood and cellular requirements – resulting in blood calcium loss
When diet is high in phosphorus, we can lose extra calcium through the urine, resulting in calcium being pulled from our bones.
High amounts of phosphorus is found in meats, soft drinks (ie. Phosphoric acid), processed foods, lunch meats and cheese spreads – this imbalance may lead to kidney stones, calcification and atherosclerotic plaque
Recommended daily intake:
Health Canada suggests that adults under the age of 50 get 1,000 milligrams of calcium per day. It recommends adults over the age of 50 get 1,200 mg of calcium each day.
TOO MUCH CALCIUM:
When Calcium levels are too high relative to magnesium and blood levels of phosphorous, it can result in soft tissue calcification and/or kidney stones. Therefore the upper limit on calcium has been set at 2500mg day – no more!
There are many different types of calcium supplements on the shelf; however, the best to choose between are calcium carbonate and calcium citrate.
Always remember never to take more than 500mg of elemental calcium at a time for optimal absorption. Any more will DECREASE the amount that’s absorbed.
Look at ELEMENTAL calcium (not total calcium). Elemental calcium is the amount of Absorbable calcium
This is the most common and least expensive calcium supplement.
It must be taken with food more best absorption
Calcium carbonate is 40% elemental calcium. Therefore, 1000 mg will provide 400 mg of calcium.
his is commonly found in antacids (such as tums)
It is more easily digested and absorbed than calcium carbonate
Best taken on an empty stomach
Calcium citrate is about 21% elemental calcium (which is less than calcium carbonate) where 1000 mg will provide 210 mg of calcium.
It is more expensive than calcium carbonate and more of it must be taken to get the same amount of calcium.
This is best for those with low stomach acid
Also has less incidence of constipation and gas than calcium carbonate
Sources of Calcium:
Many of us think MILK is the only form of calcium. However, this is NOT the case – which can be good news for those who are lactose intolerant, have milk allergies, sensitivities vegans/vegetarians, or those who just don’t like milk!