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."