All You Want To Know About Calcium And Calcium Supplements

Mayo Clinic Report:

Calcium is important for optimal bone health throughout your life. The Institute of Medicine recently updated the recommended daily allowance (RDA) for calcium and vitamin D. Does your diet deliver?
Although diet is the best way to get calcium, calcium supplements are an option if your diet falls short. Before you consider calcium supplements, though, be sure you understand how much calcium you need, the pros and cons of calcium supplements, and which type of calcium supplement to choose.

The benefits of calcium

Your body needs calcium to build and maintain strong bones. If your body lacks sufficient calcium over many years, you could face health problems related to weaker bones:
· Children may not reach their full potential adult height.
· Adults may have more bone fractures.
· The risk of osteoporosis increases.
Some research studies have suggested that calcium, along with vitamin D, may have benefits beyond bone health, perhaps protecting against cancer, diabetes and high blood pressure. But definitive evidence about such health benefits is lacking.

Calcium requirements

How much calcium you need depends on your age and sex. Note that the upper limit in the chart represents the safe boundary — it's not how much you should aim to get. If you exceed the upper limit, you increase your risk of health problems related to excessive calcium.

Recommended Dietary Allowance (RDA) for calcium for adults

Men, age in years RDA each day, in milligrams (mg) Upper limit each day, in milligrams (mg)
19-50 1,000 2,500
51-70 1,000 2,000
71 and older 1,200 2,000
Women, age in years
19-50 1,000 2,500
51 and older 1,200 2,000
Pregnant women, age in years
19-50 1,000 2,500
Breast-feeding women, age in years
19-50 1,000 2,500

Source: Institute of Medicine, 2010

Calcium and diet

Your body doesn't produce calcium, so you must get it through other sources. Calcium can be found in a variety of foods, including:
· Dairy products, such as cheese, milk and yogurt
· Dark green leafy vegetables, such as broccoli and kale
· Fish with soft bones that you can eat, such as sardines and canned salmon
· Calcium-fortified foods and beverages, such as soy products, cereal and fruit juices
In general, one serving of each of these calcium-rich foods provides about 300 to 400 milligrams (mg) of calcium, or about one-third of the RDA.
Even if you eat a healthy, balanced diet, you may find it difficult to get enough calcium if you:
· Follow a vegan diet
· Have lactose intolerance, because you may limit dairy products
· Consume large amounts of protein or sodium, which can cause your body to excrete calcium
· Have osteoporosis
· Have osteopenia
· Are receiving long-term treatment with corticosteroids
· Have certain bowel or digestive diseases that decrease your ability to absorb calcium, such as inflammatory bowel disease and celiac disease
In these situations, calcium supplements may help you meet your calcium requirements.

Types of calcium supplements

With the wide range of calcium supplements available in different doses, preparations and combinations, choosing one can be confusing. What's best for you depends largely on your needs and preferences, including any medical conditions you have or medications you take. There's not one best type of calcium supplement for everyone.
The mineral calcium — often referred to as elemental calcium — exists naturally along with other substances, called compounds. Several different kinds of calcium compounds are used in calcium supplements. Each compound contains varying amounts of elemental calcium. Common calcium supplements may be labeled as:
· Calcium carbonate (40 percent elemental calcium)
· Calcium citrate (21 percent elemental calcium)
· Calcium gluconate (9 percent elemental calcium)
· Calcium lactate (13 percent elemental calcium)

In addition, some calcium supplements are combined with vitamins and other minerals. For instance, some calcium supplements may also contain vitamin D or magnesium. Check the ingredient list to see which form of calcium your calcium supplement is and what other nutrients it may contain. This information is important if you have any health or dietary concerns.

Timing matters: When to take calcium supplements

In general, you can take calcium supplements at any time of day. But there are special circumstances that may affect when you should take calcium supplements.
· Dosage. Calcium is absorbed most efficiently when it's taken in amounts of 500 or 600 mg or less at one time. So if you take 1,000 mg of calcium a day, split it into two or more doses over the course of the day.
· Other supplements. Calcium can affect or be affected by other supplements. If you also take an iron supplement, for instance, don't take it at the same time as you take calcium. Check with your doctor, pharmacist or dietitian about other interactions.
· Medications. If you take prescription medications, ask your doctor or pharmacist about possible interactions with calcium supplements. You may need to take calcium supplements several hours before or after taking your medications.
· Meals and snacks. If your calcium supplements contain calcium carbonate, take them with food. The stomach acid produced when you eat helps the absorption of calcium carbonate. If your calcium supplements contain calcium citrate, you can take them with or without food.
If you're still not sure about the best time to take your calcium supplements, check with your doctor or pharmacist for guidance.
Who should skip calcium supplements?
Calcium supplements aren't for everyone. For instance, if you have a health condition that causes excess calcium in your bloodstream (hypercalcemia), you should avoid calcium supplements. If you have a history of kidney stones, or if you aren't sure if calcium supplements are appropriate for your situation, talk to your doctor.

Too much calcium has risks

Dietary calcium is generally safe, but more isn't necessarily better, and excessive calcium doesn't provide extra bone protection. In fact, if the calcium in your diet and from supplements exceeds the upper limit set by the Institute of Medicine, you could increase your risk of such health problems as:
· Kidney stones
· Prostate cancer
· Constipation
· Calcium buildup in your blood vessels
· Impaired absorption of iron and zinc
If you take calcium supplements and eat calcium-fortified foods, you may be consuming more calcium than you realize. Check your calcium supplement to see how much it contains and read food labels to help monitor your total calcium intake.

Don't forget vitamin D with your calcium

At the same time that the Institute of Medicine released its recommendations for calcium intake, they also released new recommendations for vitamin D. Vitamin D is also important for bone health and helps your body absorb calcium. Some calcium supplements contain vitamin D. A few foods naturally contain small mounts of vitamin D, such as canned salmon with bones, and egg yolks. You can also get vitamin D through fortified foods or even sun exposure.

Scientists See Dangers in Energy Drinks

New York Times Report:

With widespread alarm about deaths linked to alcohol-and-caffeine-laced commercial drinks like the fruity malt beverage Four Loko, it’s easy to overlook problems that may be linked to the so-called energy drinks that spawned them.

But a number of scientists are worried about highly caffeinated beverages like Red Bull, Rockstar, Monster and Full Throttle, which are popular among teenagers and young adults.

The often bizarre combination of ingredients in these drinks prompted three researchers from the University of Texas Health Science Center at Houston and the University of Queensland in Australia to examine what is known — and not known — about the contents of these beverages, which are sold alongside sodas and sport drinks in supermarkets, drugstores and highway rest stops.

Their review of all the studies in English in the scientific literature, published in November in The Mayo Clinic Proceedings, led them to question both the effectiveness and safety of energy drinks.

Long-Term Effects Unclear

The researchers noted that the drinks contain high levels of caffeine and warned that certain susceptible people risk dangerous, even life-threatening, effects on blood pressure, heart rate and brain function.

The authors noted that “four documented cases of caffeine-associated death have been reported, as well as five separate cases of seizures associated with consumption of energy/power drinks.” Additional reports include an otherwise healthy 28-year-old man who suffered a cardiac arrest after a day of motocross racing; a healthy 18-year-old man who died playing basketball after drinking two cans of Red Bull; and four cases of mania experienced by individuals known to have bipolar disorder.

Using an abbreviation for energy beverages, Dr. John P. Higgins and co-authors wrote in the Mayo journal that because “teens and young adults, both athletes and nonathletes, are consuming E.B.’s at an alarming rate, we need to determine whether long-term use of E.B.’s by this population will translate into deleterious effects later.”

His co-author Troy D. Tuttle, an exercise physiologist at the Houston university, said in an interview: “Almost all the studies done on energy drinks have involved small sample sizes of young, healthy individuals in whom you’re unlikely to see short-term ill effects.

“But what about the long term? What about liver and cardiovascular disease, insulin resistance and diabetes? We could speculate about a lot of possible problems, but we just don’t know.”

He urged the Food and Drug Administration to “step in and regulate this market,” which currently has few restrictions on the kinds and amounts of ingredients and the claims that are made about them. Manufacturers have labeled the beverages “dietary supplements,” which absolves them of the federal regulations that govern sodas and juices and allows producers to make “structure and function” claims, like “Enhances athletic performance” and “Increases caloric burn and mental sharpness.”

As Mr. Tuttle described the marketing strategy for energy drinks, “the companies have taken a cup of coffee — or two or more cups of coffee, added a lot of hip-sounding stuff and marketed it with a hot, modern, trendy push for young people who want to look cool walking around with a can of Red Bull.

“Anyone can buy these drinks, even 11- and 12-year-old kids.”

In an e-mailed statement, the American Beverage Association said, “Most mainstream energy drink brands voluntarily put statements on their containers, including advisories about use by people sensitive to caffeine.” Also, the organization said many of its members voluntarily list the amount of caffeine on their product labels or have provided caffeine content information through their Web sites and consumer hot lines.

Kevin A. Clauson, a doctor of pharmacy at Nova Southeastern University in West Palm Beach, Fla., who had previously reviewed safety issues surrounding energy drinks said that his main concerns were “the amount of caffeine, which can be injurious particularly to people with a pre-existing cardiovascular abnormality” and “the effects of these drinks when they are combined with alcohol, which can have disastrous consequences.”

After several states made moves to ban Four Loko, it was reformulated to remove the caffeine and two other ingredients, guarana and taurine, but Dr. Clauson said that was “unlikely to have a substantial impact” on young people, who will continue to combine alcohol with energy drinks. The caffeine and caffeinelike ingredients in these drinks can mask the perception of inebriation — and that can increase the risk of drunken driving or other dangerous behaviors.

Mr. Tuttle, who works with sports teams, is concerned about the effects of energy drinks on athletic performance. “A lot of kids are reaching for energy beverages instead of sport drinks, which unlike the energy drinks are mostly water with a nominal amount of sugar and electrolytes,” he said. “The energy drinks contain a slew of ingredients, most of which are unresearched, especially in combination with one another.”

A Potent Brew

For an athlete engaged in intense exercise, the high doses of sugar in energy drinks can impair absorption of fluids and result in dehydration. A 16-ounce can of an energy drink may contain 13 teaspoons of sugar and the amount of caffeine found in four or more colas. Mr. Tuttle noted that caffeine, which is known to improve muscle action and performance, especially in endurance activities, is banned in many sports competitions. Thus, consuming an energy drink close to an event could disqualify an athlete.

Other ingredients often found in energy drinks include taurine, glucuronolactone, B vitamins, ginseng, guarana, ginkgo biloba and milk thistle. Mr. Tuttle calls guarana particularly worrisome because it acts as a stimulant, like caffeine.

“The B vitamins, which are important enzymes for energy utilization, are added to legitimize the high levels of sugar,” he said. “But the American diet, which is very high in protein, already has plenty of B vitamins. These drinks are a kind of sensory overload for the body, with too much stuff coming in at the same time.”

Adding alcohol to the mix, as some consumers were doing even before drinks like Four Loko came along, can be a recipe for disaster. Under the stimulation of energy drinks, people may think they are sober when they are not. Such was the fate of Donte’ Stallworth, a wide receiver for the Cleveland Browns who killed a pedestrian with his car in March 2009 after drinking multiple shots of tequila and a Red Bull. Mr. Stallworth said he did not feel intoxicated at the time of the accident.

“Caffeine is being treated as a flavoring agent, not a drug,” Dr. Clauson said. “The average healthy person who consumes one serving of an energy drink is unlikely to encounter difficulty.” Those most likely to get into trouble, he said, are “toxic jocks” who overindulge and those with an underlying heart condition.