April 13, 2011 -- Do you take vitamins every morning? The numbers are growing. A new government study found that more than half of American adults take at least one dietary supplement. But despite their popularity, many experts remain skeptical of their effects.
"Although we were not surprised, it is interesting to note that not only did supplemental calcium use and vitamin D use increase for all women aged 60 and over from 1988 to 1994 to 1999 to 2002, but there was also an increase from [between] 1999 [and] 2002 to 2003 to 2006," said Jaime Gahche, a nutritional researcher with the National Center for Health Statistics and lead author of the study.
Supplements can contain high amounts of specific nutrients, and are often used to increase nutrition in a person's diet.
Because so many Americans use vitamin supplements, researchers hoped to assess people's use of them in order to get an accurate picture of the population's dietary intake.
The study, sponsored by the Centers for Disease Control and Prevention's National Center for Health Statistics, found that more than 40 percent of Americans used supplements from 1988 to 1994, and more than one half took vitamins from 2003 to 2006. Multivitamins were found to be the most commonly used supplement.
Of particular interest to the researchers were vitamin D, calcium and folic acid supplements.
Too Much Hype?
ABC News contacted several experts on the subject. While none was surprised by the increased use of vitamins, nearly all of them agreed that a healthy diet is a better alternative to nutrients in pill form.
"People are looking for help with what they believe is a problem but trying to solve it the wrong way," said Dr. Darwin Deen, clinical professor in the department of family and social medicine at Albert Einstein College of Medicine in New York. "Our diet contains too many processed foods that do not have the nutrients we need to keep us healthy -- soda and chips -- so people respond by taking vitamins."
Deen said he usually advises his patients to increase their intake of fruits and vegetables to boost their vitamin count, rather than take a pill.
"The pill is a nice idea, but we have no reason to think this one-size-fits-all dose makes any sense for each individual," said Deen.
Lead author Gahche said the report makes no recommendations on whether or not a person should or should not use dietary supplements. And if individuals are taking supplements, they should be sure to the tell their doctors what those are and why they're taking them.
"There probably is a perception among the population that taking a dietary supplement is an easy way to obtain necessary nutrients and improve health, but this isn't necessarily true," said Dr. Donald Hensrud, associate professor of preventive medicine and nutrition at Mayo Clinic. "For most dietary supplements there is not a lot of evidence they improve health, including multivitamins.
"There is also some data that, in general, the people who take dietary supplements are least likely to need them… they already have a good diet."
Vitamins and Supplements: Fruits and Vegetables Better
Doctors have studied the effects of vitamin D on a variety of health conditions, including cholesterol, heart disease, influenza, breast cancer and osteoporosis, just to name a few.
The vitamin is important to the body as it aids in the absorption of calcium, which in turn helps to form and maintain healthy bones. And the report found that supplemental calcium increased from 28 percent to 61 percent among women aged 60 and older in the past two decades.
"Too many people are taking calcium to prevent osteoporosis but not paying attention to their vitamin D status," said Deen. "Without adequate vitamin D, you do not absorb your calcium supplement, making it a waste of money."
Natural sources of vitamin D include fatty fish, eggs, mushrooms exposed to sunlight, cod liver oil and ultraviolet rays from the sun. Many doctors recommend 10 to 15 minutes of sun exposure per day to prevent vitamin D deficiency.
Vitamin D Deficiency Leads to Disease
A deficiency of the vitamin causes rickets in children and a softening of the bones and osteoporosis in adults.
"Vitamin D and calcium [supplements] are the flavors of the month and it's the impulsive nature of our society to get that quick fix instead of getting back to eating whole foods," said Dr. Stephen Cook of University of Rochester Medical Center in New York.
As a pediatrician in upstate New York, Cook said many people in the area likely have low levels of vitamin D, but even then, Cook said he's not sold on supplements.
"There is a good chance we all have low levels of vitamin D [in upstate New York], but if you live healthily and get two or three servings of low-fat dairy each day, you're probably going to get enough."
And even for children suffering from rickets, Cook said there is a large debate in pediatrics as to the benefits of giving them vitamin D supplements.
"The short-term approach is to supplement them, but really, we should say, 'no, make sure they're drinking enough milk,'" said Cook.
Folic Acid for Mother and Baby Health
Folate has been proven to prevent neural tube effects and pregnancy complications. Doctors recommend that women who are pregnant or trying to get pregnant take prenatal supplements that include high doses of folic acid. They may not be able to get enough from leafy green vegetables, beans, egg yolks and fortified grains.
In the study, folic acid supplement use has not increased in more than two decades, and white women were more likely to take the vitamins than black and Hispanic women were.
"It is unfortunate that folic acid use among young women has not increased and is still relatively low, particularly among minorities," said Hensrud. "Folic acid to prevent neural tube defects is one of the more beneficial examples of dietary supplements."
How to Get Your Vitamin Fix
"Dietary supplements play a role in a healthy lifestyle," Steve Mister, President & CEO of the Council for Responsible Nutrition, a dietary supplement trade group, told ABC News. "But they are supplements to, not substitutes for, a healthy diet. They should be used in combination with other healthy habits, like trying to eat a balanced diet, exercising regularly and seeing your doctor."
Lead author Gahche advised consumers to visit the National Institutes of Health's Office of Dietary Supplements website, which contains valuable and reliable information to strengthen knowledge and understanding of dietary supplements.
"People should realize the evidence supporting a health supporting diet is magnitudes greater than the evidence supporting dietary supplements," said Hensrud. "And eating a healthy diet can be enjoyable and taste a lot better."