By Karen Rowan
MyHealthNewsDaily

Taking supplements is common among U.S. adults, and the most oft-cited reasons people give for taking them are wanting to feel better, improving energy levels and boosting the immune system, a new survey finds.

But these aims have little to do with measurable improvements to health, the researchers said. Moreover, most people taking supplements indicated that the supplements' proven effectiveness didn't matter to them — only 25 percent said they would stop taking a supplement if it was found to be ineffective, according to the survey.

"We call this the 'effective for me' attitude," said study researcher Kathleen Weldon, of the Harvard School of Public Health in Boston. "As long as something is safe, people think they are a better expert on whether it works for them, better than any clinical trial."

People who put stock in effectiveness data tend to be "taken aback" by such thinking, she said, and wonder why a person would keep taking a supplement that hasn't been shown to work. "It's a very interesting thing to think about, in terms of scientific validity," she said. "But it's hard to argue against —what if this person is the one in a million that it's doing something for?"

The findings are based on data from a nationally representative sample of about 1,600 adults.

Participants reported using a range of products, including herbal supplements such as ginseng, probiotics such as acidophilus, amino acids, garlic pills and supplements derived from algae.  (The researchers told the study participants not to include vitamins or minerals they were taking.)

About 38 percent said they had taken a dietary supplement in the last two years, and 1 in 7 reported taking supplements regularly, the survey showed. These findings are in line with what other studies have found, Weldon said.

The most commonly used supplement was fish oil, or other omega-3 fatty acid supplements — about 24 percent of adults have used them in the last two years.  

More than a third of participants said they hadn't told their doctor about their supplement use.

"People should tell their doctors what they're taking," Weldon said. Supplements may interact with a patient's prescription medications, he said.

Another reason to tell the doctor is to make them aware of health conditions the patient is trying to treat with a supplement, she said. "Sometimes, people take supplements to lower their high cholesterol, treat arthritis or high blood pressure, to treat digestive issues — as part of the picture of good care, that communication should be there."

The article was published Nov. 19 in the journal Archives of Internal Medicine.

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courtesy of Dr. Dean Rising

Dr. Dean Rising, 72, of Springfield, Mo., took daily pills for 30 years as part of his participation in two phases of the Physicians' Health Study, which has found that a daily multivitamin cuts men's cancer risk. Rising is shown here with his pill pack in Antarctica. As it turns out, he got the dummy pills, not the multivitamins in the randomized controlled trial.

After years of research showing dietary supplements failed to prevent cancer, a new study of multivitamin use in men has a surprising message: This one worked.

Turns out, a daily dose of Centrum Silver multivitamins reduced the total risk of cancer in study participants by 8 percent, according to gold-standard research that included nearly 15,000 male doctors older than 50 for up to 13 years.  

“It does appear that there is a modest reduction in cancer among middle-aged and older men,” said Dr. J. Michael Gaziano, chief of the division of aging at Brigham and Women’s Hospital and a researcher at the VA Boston Healthcare System.

The study also found that multivitamin use cut site-specific cancers, except for prostate cancer, by 12 percent, and suggested a 12 percent reduction in deaths caused by cancer, though that figure wasn’t statistically significant.

“Even total mortality went in the right direction,” said Gaziano, whose new data comes from the Physicians Health Study II published Wednesday in the Journal of the American Medical Association.

The finding is important in a country where more than half of U.S. adults use dietary supplements, according to the Centers for Disease Control and Prevention --  and where the most common supplement is a daily multivitamin.

Several recent studies -- including Gaziano’s own work -- have looked at whether taking specific vitamins such as C, E and B12 prevent cancer.  They’ve come up empty; a few even found a higher risk of certain illnesses.

The difference, Gaziano said, is that many of those studies were limited in scope and size and they used single supplements at high doses, much higher than a daily vitamin would provide.

By contrast, the new study is the first of its kind.

“The Physicians' Health Study II represents the only large-scale, randomized, double-blind, placebo-controlled trial testing the long-term effects of a common multivitamin in the prevention of chronic disease,” the authors write.

Study participants included 14,641 U.S. men, all doctors, who received either a pack of daily supplements, including the Centrum Silver vitamins, or daily dummy pills between July 1997 and June 2011.

The doctors, who were followed for between 10 and 13 years, were excellent patients. They were pretty healthy, with a mean body mass index of 26 -- just barely overweight -- and only 3.6 percent of them smoked.  They were also good sports: By the end of the trial, more than two-thirds of the docs were still taking their pills as directed, the study found.

“They are very compliant,” Gaziano said.

Take Dr. Dean Rising, 72, a Springfield, Mo., pediatrician who has participated in both phases of the Physicians' Health Study, two large-scale studies spanning 30 years. He took photos of himself and his daily "vitamins" on seven continents, including a shot a few years ago in Antartica. 

"This is the sort of thing where if you don't have people testing these things, you never know the results," explained Rising. 

As it turns out, he learned last year that he was enrolled in the placebo arm of the Phase II study, so he never got any vitamins at all. Now, he says, he makes sure to take one every day. 

"I think it means you need a variety of different vitamins in your diet," he said of the new results.

Experts agree. The new study suggests that boosting nutrition, even with the modest nudge of a daily vitamin, could have far-reaching health benefits, said Dr. Demetrius Albanes, a senior investigator and expert in nutritional epidemiology with the National Cancer Institute.

“It’s exciting. It’s encouraging,” said Albanes.

But others cautioned that it’s too soon to make sweeping recommendations based on a single study, especially when previous trials have been mixed or have even shown harm, said Susan Gapstur, vice president of the epidemiology research program for the American Cancer Society.

“It’s important to remember that this study, as credible as it is, is still just one trial,” said “Typically we like to see these kinds of findings replicated by other studies, and in other populations, before coming to solid conclusions.”

In addition, the trial only included men who are healthier than the general population, and, of course, it excluded women. Further research would need to conduct a similar test of multivitamin use in women to determine whether that also reduced cancer risk, experts said.

Still, the results of the study could send some older men racing to buy bottles of Centrum Silver, the best-selling multivitamin produced by Pfizer, the drug company that now owns the brand. Gaziano said he picked that multivitamin early on because he thought it was a quality product that would "last over the years."

An estimated 18 million multivitamins and 18 million placebo pills were donated during the course of the trial, said MacKay Jimeson, a Pfizer spokesman who noted that the company is “very pleased” that researchers chose Centrum Silver for the study.

Gaziano said the pills and packaging were the extent of his drug company support.

For his part, Gaziano is pleased not only with the results, but also with finishing a project that occupied 17 years of his life.

“As a long-term chronic disease trialist, it feels very good to be done,” he said. “You just have to be patient. I think that when we’re talking about prevention of cancer, we’re talking about decades.”

Related stories: 

• More bad supplement news: Vitamin E may be risky for prostate
• Vitamin D doesn't actually fight off colds, study finds

By MyHealthNewsDaily Staff

Americans may not eat the healthiest diets, but most get adequate levels of essential vitamins and nutrients, according to a new report from the Centers for Disease Control and Prevention.

For most nutrients, less than 10 percent of the population is deficient, the report showed.

However, deficiency rates vary by age, gender and ethnicity, and close to a third of African-Americans were deficient in vitamin D, the report said.

These higher deficiency rates are a concern and need more attention, said study researcher Christine Pfeiffer, of the CDC’s National Center for Environmental Health.

The report gave the results of an analysis of blood and urine samples collected from people between 2003 and 2006, measuring levels of 58 nutrient markers.

For the U.S. as a whole, 10.5 percent of people were deficient in vitamin B6, 8.1 percent were deficient in vitamin D, 6.7 percent were deficient in iron, 6 percent were deficient in vitamin C, 2 percent were deficient in Vitamin B12, and less than 1 percent were deficient in vitamin A, E and folate.

Vitamin D deficiency was 31 percent among African-Americans, 12 percent among Mexican-Americans and 3 percent among whites. Further research is needed to explain why non-Hispanic blacks have better bone health but yet have a higher rate of vitamin D deficiency, the report noted.

Iodine levels among women ages 20 to 39 years may need improvement. This age group had iodine levels that were, on average, just above iodine insufficiency, the report said.

Iodine is an essential component of thyroid hormones, which regulate growth and development. Iodine is especially important in women during childbearing years to ensure proper brain development of the fetus during pregnancy.

The report found higher rates of iron deficiency among Mexican-American children ages 1 to 5 (11 percent), blacks (16 percent), and Mexican-American women of childbearing age (13 percent) when compared with other race/ethnic groups.

One particular public health success story has been increases in folate levels in recent years. Blood folate levels in are 50 percent higher in all ethnic groups since the country began fortifying cereal-grain products with folic acid in 1998, the report said.

The CDC plans to further analyze the data to identify the influence of socioeconomic and lifestyle factors on levels of nutrient levels, the agency said.

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Could taking one of these vitamins lead you down the path of bad behavior? Yes, say researchers.

Taking supplements may lead to poorer health, not because of what they do to your body, but what they do to your mind.

When people take supplements they get a false sense of invulnerability, a new study shows. And that can translate into a greater tendency to head down the path of risky behavior.

The intriguing study published in Psychological Science, found that people didn’t even need to be given real supplements for this devil-may-care attitude to develop – they just needed to be told they were swallowing something healthful.

For their study, Taiwanese researchers gave placebo pills to 82 volunteers, half of whom were told the capsules contained vitamins. The rest were told the truth – that these were simply sugar pills.

The big surprise came when the researchers surveyed the two groups. Those taking phony supplements reported a greater sense of invulnerability and less of a desire to exercise. They also were more likely to consider engaging in casual sex, sunbathing and binge-drinking.

At the end of the study the two groups were told they could choose between a healthful meal and an all-you-can-eat buffet. Sure enough, more of those in the group who were told they'd taken a supplement said they’d prefer the buffet.

The findings come as no surprise to Leslie Bonci, director of sports nutrition at the University of Pittsburgh Medical Center.

“You see this even in professional athletes,” Bonci said. “Sometimes they attribute to supplements superhuman properties that let them off the hook for healthy behaviors. They’ll say, ‘I’m taking this supplement so it doesn’t matter what I eat.’”

Bonci lays the blame on ads that show healthy fit people taking supplements. You don’t see this kind of advertising for all the foods that actually do lead to good health she said.

And those ads lead to unreasonable expectations, Bonci said.

“We this face challenge every day,” she added. “And it’s not just athletes. There are many patients who believe there is exercise in a bottle.”

People have just come to expect that pills can cure everything, said Dr. Andrew Leuchter, a professor of psychiatry and director of the Laboratory of Brain, Behavior and Pharmacology at the University of California, Los Angeles.

“We live in a society that is very oriented towards taking medication,” Leuchter said. “People feel like they can take a pill and it will almost immunize them from any unhealthy lifestyle choices”

And then there’s the fact that human beings are very good at keeping two contradictory ideas in their heads at once. “It’s one of those quirks of human nature,” Leuchter said. “We do something we think will enhance our health but at the same time we’re happy to do something that may in the long term be detrimental.”

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