Ulcerative colitis associated with the herbal weight loss supplement Hydroxycut

The Prevalence of Dietary Supplement Use among College Students: A Nationwide Survey in Japan

To clarify the prevalence of dietary supplement use among college students, we conducted Internet-based nationwide questionnaire surveys with 157,595 Japanese college students aged between 18 to 24 years old who were registrants of Macromill Inc. (Tokyo, Japan). Among the 9066 respondents (response rate 5.8%), 16.8% were currently using dietary supplements. The prevalence of dietary supplement use did not differ significantly between males (17.1%) and females (16.7%). However, it increased according to their grade (13.1% to 20.5%), and it was higher in medical and pharmaceutical college students (22.0%) compared to others (16.7%). The main purpose of dietary supplement use was for the health benefits in both males and females. Other reasons were to build muscle in males, and as a beauty supplement and for weight loss in females. According to the purpose of dietary supplement use, the most commonly-used dietary supplements were vitamin/mineral supplements in both males and females, then protein and weight loss supplements in males and females, respectively. Although most students obtained information about dietary supplements via the Internet, they typically purchased the supplements from drug stores. Of the students surveyed, 7.5% who were currently using or used to use dietary supplements experienced adverse effects, with no significant difference between genders (8.8% in male, 7.0% in female). In conclusion, the prevalence of dietary supplement use increased with grade among college students in Japan. Some of them experienced adverse effects. Education may be important to prevent adverse effects resulting from supplement use in college.

Behaviors of consumers, physicians and pharmacists in response to adverse events associated with dietary supplement use

Background

The prevalence of dietary supplements has increased in Japan, and, as a consequence, the adverse events associated with dietary supplement use have become more prominent. Severe adverse events must be reported to the Japanese government via public health centers. However, the number of cases reported to the Japanese government is limited. To clarify this discrepancy, we conducted an internet questionnaire, and surveyed how consumers, physicians and pharmacists acted when they or their patients developed adverse events due to dietary supplement use.

Methods

This study was completed by 2732 consumers, 515 physicians, and 515 pharmacist via internet surveillance on November 2015.

Results

Although 8.8% of consumers developed adverse events including diarrhea, constipation, stomachache, headache, and nausea and vomiting, most of them did not report their adverse events to public health centers. However, some consumers went to hospitals because of adverse events. We also surveyed how physicians and pharmacists acted when their patients developed adverse events due to dietary supplement use. Most physicians and pharmacists did not report these cases to public health centers because they were unable to definitively prove the cause-and-effect relationship of these adverse events. Furthermore, some physicians and pharmacists did not know how or where to report these adverse events.

Conclusions

We clarified the reasons for the limited number of reports of adverse events to the Japanese government in this survey. It is important to encourage not only consumers, but also physicians and pharmacists to report adverse events to public health centers. In addition, an analyzing tool of cause-and-effect relationships might be helpful for physicians and pharmacists.

Electronic supplementary material

The online version of this article (doi:10.1186/s12937-017-0239-4) contains supplementary material, which is available to authorized users.