Fewer people are taking fish oil, vitamin C and calcium supplements, according to a recent survey of dietary supplement users.
The survey, conducted by Consumerlab.com, also showed that the number of people using probiotics has increased.
"The changes in supplement use seem to reflect research findings that made headlines this past year, as well as a shift in promotional emphasis for some of these supplements," Dr. Tod Cooperman, M.D., the president of ConsumerLab.com, said in a statement.
"In the past, probiotics were marketed mainly to women and for irritable bowel syndrome, but are now finding a wider audience due to expanded treatment applications, including antibiotic-related diarrhea, diverticular disease and even anxiety," Cooperman said. "Meanwhile, too much calcium has been shown to pose increased risk of cardiovascular disease, while high-dose vitamin C appears to increase the risk of kidney stones and cataracts. The benefits of fish oil now seem largely limited to people who don't eat fish or have high triglycerides."
The survey included more than 10,000 people, and respondents were all classified as "heavy" users of supplements (taking 6.6 supplements a day, on average).
Calcium supplement use declined from 2012 to 2013, with its use in women specifically decreasing from 57.8 percent to 45.6 percent. And vitamin C supplement use declined among men from 42.3 percent to 35 percent.
And even though fish oil was still the most-used supplement -- used by 67.2 percent of respondents -- its use decreased 4 to 5 percent from 2012 to 2013, the survey showed.
Meanwhile, probiotic use increased, with its use among men specifically increasing from 30.5 percent to 37.1 percent.
The survey also revealed the most-used supplements:
1. Fish oil - used by 67.2 percent of respondents (a decrease of 4.5 percent from 2012).
2. Multivitamins - used by 63.8 percent of respondents (a decrease of 1.6 percent from 2012).
3. CoQ10 - used by 54.1 percent of respondents.
4. Vitamin D - used by 53.8 percent of respondents (a 1.7 percent decrease from 2012).
5. B vitamins - used by 43.1 percent of respondents (a decrease of 1.1 percent from 2012).
6. Calcium - used by 42.1 percent of respondents (a 6.3 percent decrease from 2012).
7. Magnesium - used by 38.1 percent of respondents.
8. Probiotics - used by 37.8 percent of respondents (a 3.4 percent increase from 2012).
9. Vitamin C - used by 37 percent of respondents (a 4.2 percent decrease from 2012).