Calcium Deficiency and Effects on Health
Calcium is a common mineral found in many foods. The body needs calcium to maintain strong bones, for muscles to do their job properly and nerves to carry messages between the brain and the rest of the body. Calcium is also used to move blood and manage the release of various hormones and enzymes that affect almost every function in the body. Almost all calcium is stored in bones and teeth, where it supports their structure and hardness.
Calcium is found in many foods, including milk, yogurt, cheese, kale, broccoli and Chinese cabbage as well as in fish with soft bones such as canned sardines and salmon. Calcium is traditionally added to some breakfast cereals, fruit juices, soy and rice beverages and tofu. Finally, breads, pastas and unfortified cereals also add significant amounts of calcium to the typical American diet.
Certain groups of people are more likely than others to have trouble getting enough calcium. If you have a calcium deficiency for any reason, you may benefit from incorporating a green supplement into your diet that has calcium in it. People who typically struggle with getting enough calcium include:
- Postmenopausal women, because they experience greater bone loss and do not absorb calcium as well.
- Women of childbearing age whose menstrual periods stop because they exercise heavily, eat too little or both.
- People with lactose intolerance experience bloating, gas and diarrhea when they drink more than small amounts of milk at a time. However, they can eat other calcium-rich dairy products that are low in lactose, such as yogurt and many cheeses.
- Vegans and ovo-vegetarians avoid dairy products that are a major source of calcium.
- Many other general factors can affect the amount of calcium absorbed from the digestive tract, including:
- Age - efficiency of calcium absorption decreases as people age, which is why recommended calcium intakes are higher for people over age 70.
- Vitamin D intake - this vitamin is produced in the body when skin is exposed to sunlight and it increases calcium absorption.
- Components in food - such as oxalic acid in some vegetables and beans and phytic acid in whole grains can reduce calcium absorption.
- Factors that affect how much calcium the body eliminates - including alcohol and caffeine containing beverages as well as nutrients such as protein, sodium, potassium and phosphorus.
Inadequate calcium intake does not produce obvious symptoms in the short term because the body maintains calcium levels in the blood by taking it from bone.
Over the long term, consumption below recommended levels can have serious negative health consequences, such as causing low bone mass and increasing risk of osteoporosis and bone fractures.
This is why many doctors advise patients to supplement their diet with extra calcium by drinking green drinks and eating produce high in calcium.
These are some of the ways in which calcium is known to affect health:
- Bone health - bones need plenty of calcium and vitamin D throughout childhood and adolescence to reach their peak strength and calcium content by about age 30. After that, bones slowly lose calcium, but these losses can be reduced by getting recommended amounts of calcium throughout adulthood and by having a healthy, active
- lifestyle that includes weight-bearing physical activity such as walking and running.
- Osteoporosis - is a disease of the bones in older adults especially women in which the bones become porous, fragile, and more prone to fracture. Osteoporosis is a serious public health problem for more than 10 million adults over the age of 50 in the US. Adequate calcium and vitamin D intakes as well as regular exercise are essential to keep bones healthy throughout life.
- Heart disease and stroke - studies show that getting enough calcium might protect people from heart disease and stroke. But other studies show that some people who consume high amounts of calcium, particularly from supplements, might have an increased risk of heart disease.
- High blood pressure (BP) - some studies have found that getting recommended intakes of calcium can reduce the risk of developing high BP or hypertension. One large study in particular found that eating a diet high in fat-free and low-fat dairy products, vegetables and fruits lowered BP.
The two common forms of calcium dietary supplements are carbonate and citrate.
Calcium carbonate is inexpensive and is absorbed best when taken with food. Calcium citrate, a more expensive supplement, is absorbed well on an empty or a full stomach.
People with low levels of stomach acid absorb calcium citrate more easily than calcium carbonate. Other forms of calcium in supplements and fortified foods include gluconate, lactate and phosphate.
Calcium supplements may cause gas, bloating, and constipation in some people. Getting too much calcium can cause constipation. In adults, too much calcium - typically from dietary supplements but not food - might increase the risk of kidney stones. Most people do not get amounts above the upper limits from food alone; excess intakes usually come from the use of calcium supplements. Surveys show that some older women in the US probably get amounts above the upper safe limit because of the common use of calcium supplements.
Your doctor, pharmacist and other health care providers can tell you if your dietary supplements might interact or interfere with your prescription or over-the-counter medicines or alternatively, if the medicines might interfere with how your body absorbs, uses or breaks down vital nutrients.
Clinical evidence suggests that chronic low-grade metabolic acidosis affects bone mass and osteoporosis. For example, a lower dietary intake of acid-producing foods meant greater spine and hip bone mineral density along with greater forearm bone mass in over 1000 women aged 45-54 years. On the other hand, a prospective, blinded study using potassium citrate in 161 postmenopausal women also showed an increase in their bone mass over a 12-month period.
Unfortunately, it is very difficult to consume the daily recommended servings of fresh veggies and fruits needed to restore the body's natural acid-base balance.