From multivitamins to calcium, dietary supplements are seen as a necessary dietary component for more than half of all Americans, according to new survey data released by the National Center for Health Statistics. The study, sponsored by the Centers for Disease Control and Prevention (CDC), found that 53 percent of U.S. adults used supplements from 2003 to 2006. This was up from about 40 percent of adults who took supplements from 1988 to 1994. Government figures show that overall growth in supplement usage leveled off after 2006 and that women continue to take more supplements than men.

The CDC survey found that the multivitamin remains to be the most popular supplement, while calcium usage has grown significantly since the early 1990s. In fact, more than 65 percent of women 60 and older take calcium supplements, up from less than 30 percent in the early 1990s.

“We’re encouraged to see the government confirm what we’ve seen about dietary supplement usage—that it’s growing,” says Council for Responsible Nutrition President and CEO Steve Mister.

CDC asks people to prove supplement usage

The latest CDC supplement usage statistics come from national, in-home surveys conducted in 1988-1994 and 2003-2008. Over the last 10 years, each annual survey included more than 2,000 people, who were asked what dietary supplements they take and were also asked to provide the bottles to very their usage.

The last piece of this survey equation is important because, as consumer researchers know, what people report in a survey is not always accurate. “What people say and what people do are usually very, very different,” says Dave Kingsbury, vice president of new product development and research at New Hope Natural Media.

CRN also annually tracks dietary supplement usage in the United States. The trade association’s latest research, which was conducted by Ipsos-Public Affairs and published last September, reported that 66 percent of U.S. adults label themselves as supplement users. In 2009, 65 percent identified themselves as supplement users compared with 64 percent in 2008; 68 percent in 2007; and 66 percent in 2006, CRN reported.

“Sales are up for this category, and our own consumer research has demonstrated steady usage by approximately two-thirds of U.S. adults—for the past seven years,” Mister said. “More than 150 million Americans take dietary supplements each year to improve their overall health, fill in nutrient gaps, and because their doctors recommend them.”

Like the latest CDC survey, CRN’s research found that a growing number of U.S. consumers are taking Vitamin D than in previous years. The findings from CRN’s 2010 survey reported that 27 percent of supplement users take a vitamin D supplement—up from 19 percent in 2009 and 16 percent in 2008. This growth has likely been fueled by the steady stream of positive research about the many health benefits of vitamin D that has been published over the last several years. The U.S. government’s recommendations for increasing daily vitamin D consumption is also driving supplementation given that it is difficult to obtain the necessary daily amount through diet and exposure to sunlight alone.

Multivitamins: A cheap insurance policy

The government’s latest supplement usage data is supported by research from Nutrition Business Journal, which has reported steady growth in U.S. consumer sales of dietary supplements since the market research group began tracking the market in 1996. Americans continued to spend more money on dietary supplements even during the latest recession, with sales growing 6.3 percent in 2008 and 6 percent in 2009 (outpacing the 5 percent compound annual growth rate the U.S. supplement category achieved from 2000-2009).

“I am surprised at how resilient supplement sales have been,” Scott Van Winkle, a managing director of Boston-based Canaccord Adams, told NBJ in 2009. “When you no longer have a job or health insurance, a multivitamin is a pretty cheap insurance policy.”

Although its final 2010 sales numbers will not be available until June, NBJ estimates that supplement sales increased another 6 percent last year. Strong sales performers in 2010 included the usual suspects: vitamin D, fish oil, probiotics and magnesium.

What is expected in 2011 and beyond?

Sales of dietary supplements are holding steady in 2011, according to Nutrition Business Journal . But with the overall economy slowing improving, some may be wondering whether supplement sales growth will continue at its 2009-2010 pace or slip under 5 percent.

Initial findings from New Hope Natural Media’s Future of Wellness ethnographic consumer research suggest that mainstream consumers believe dietary supplements can support their overall health and wellness but often are not good at compliance. Case in point: one 46-year-old New York mother told New Hope’s researchers that she would like to take more vitamins—perhaps a multivitamin and calcium supplements—but often has trouble remembering to take them. “I don’t know why,” she said.

A single mother of three in San Diego showed the New Hope team the many large jars of dietary supplements that she keeps in her cabinet and said that she wishes she could spend more time perusing the supplement section at her local natural products store, Henry’s, to learn about new supplement products and their uses. Right now, however, she “doesn’t go there” because she knows she cannot afford to buy new types of supplement products. “As my economic situation improves,” she said, “I would like to invest more in vitamins.”

Recent discussions with supplement retailers suggest that this San Diego mother’s supplement shopping habits are being carried out across the United States. “Customers cut back on supplements like eating out now, and they are still only buying what they really need,” Virginia Styles, owner of Herb Garden in Cumming, Georgia, said. “Before the recession, they might try two or three different supplements at a time, and now they buy only one.”

So how can natural product stores—which often depend on supplements for a large piece of their revenue—stay afloat and continue growing in this environment? One important piece of the equation is education. The more store employees know about supplements (and how to legally talk about them with customers, the more consumers will understand and buy into their benefits. “Most customers come in with questions on specific issues, and we will recommend different products,” Styles said. “We share the research and information we have available [with customers]. We do not try to treat or diagnose problems, however, since we are not doctors.”

Another opportunity for supplement manufacturers and retailers is to provide tools that can help with supplement compliance, such as text messages or a mobile phone app that remind people when (and how) to take their supplements.