Characterisation of vitamin and mineral supplement users differentiated according to their motives for using supplements: results of the German National Nutrition Monitoring (NEMONIT)

Dietary Intake of Micronutrients and Use of Vitamin and/or Mineral Supplements: Brazilian National Food Survey

BACKGROUND/OBJECTIVES

Vitamin and/or mineral supplements are designed to correct micronutrient deficiencies or maintain adequate intake. However, evidence suggests the indiscriminate use of these products, particularly among populations that already meet their micronutrient requirements through diet. This study aims to estimate the prevalence of vitamin and/or mineral supplement use and assess the dietary intake of micronutrients among users and non-users in the Brazilian adult and elderly populations.

METHODS

The prevalence of vitamin and/or mineral supplement use was estimated from a sample of 37,364 individuals who participated in the Brazilian National Food Survey, a module of the 2017-2018 Household Budget Survey. The average dietary intake of micronutrients-including calcium, magnesium, phosphorus, iron, copper, zinc, vitamin A, thiamine, riboflavin, niacin, cobalamin, pyridoxine, vitamin D, vitamin E, vitamin C, and folate-was calculated for both users and non-users of these supplements, based on 24 h dietary recalls collected during the survey. Analyses of dietary intake were stratified by sex and age group.

RESULTS

The estimated overall prevalence of supplement use was 16.0% (95% CI: 15.4-16.6), with a higher prevalence among women (19.5% [95% CI: 18.7-20.5]) and the elderly (27.9% [95% CI: 26.4-29.4]). Women who used vitamin and/or mineral supplements showed higher average intakes for a greater number of dietary micronutrients compared to non-users.

CONCLUSIONS

The findings from the analysis of average micronutrient intake from food sources, particularly among women and elderly women who used supplements, support the paradox of the "inverse supplement hypothesis", which suggests that individuals who use dietary supplements are often those with the least need for them.

Is Dietary (Food) Supplement Intake Reported in European National Nutrition Surveys?

Dietary (food) supplements (DSs) have seen a sharp increase in use and popularity in recent years. Information on DS consumption is vital for national nutrition monitoring. The objective of this study was to investigate whether DS intake was reported in the National Nutrition Surveys (NNSs) in all European countries. NNSs reporting DS use were retrieved via literature review (i.e., PubMed, Google Scholar, Scopus), scientific and organizational publications (EFSA), or open-published government and other official reports. Included were the European NNSs referring to adults, published in English, French, or German, post-2000. Out of the 53 European countries, 30 recorded DS intake. Among them, related findings on the percentage of DS intake were published in 21 cases, 5 of them written in the local language. DS use varied by nation, with Finland and Denmark having the greatest (over 50%) and Italy having the lowest percentage (5%). In terms of comprehensive reported data on DS consumption in Europe and the investigation of the contribution of DSs to total nutrient intake, there is a need for improvement. Common DS categories should be defined upon agreement among the involved scientific parties to allow for comparable data and estimations between surveys.

Fish oil users of Greece: Predictors, knowledge and habits regarding dietary supplement use

Background

Fish oil (FO) dietary supplements (DS) have gained popularity over the past few decades and emerged as one of the most popular DS in both Europe and the USA. However, in Greece, no study has been carried out to determine the prevalence and characteristics of FO consumers.

Objective

The aim of this study was to describe the stance (i.e., beliefs, knowledge and habits) and practices of FO users in Greece towards DS.

Methods

A cross-sectional study, using in-person questionnaires and a stratified random sampling technique, was conducted throughout 2018-2019. A total of 28491 Greek citizens over 15 years old were interviewed in 74 regional units corresponding to the 13 administrative regions of Greece. Having used DS at least once, deemed one as: DS+FO, if FO were among them; DS-FO, if FO were never used or DS non-user, if DS were never used. Pearson's chi-square test was used to determine independence between relevant outcome variables and FO use and multinomial logistic regression was performed to create models predictive of FO use.

Results

The sample consisted of 3.5% DS+FO, 51.3% DS-FO and 43.8% DS non-users, while 1.4% could not remember whether they had used DS. Significant predictors for being a DS+FO were identified. DS+FO were more likely to judge a DS-less diet as insufficient, support DS use and comprehend DS's labels. Also, DS+FO had used additional DS, considered more parameters when buying DS and were receivers of DS recommendations from more sources compared to DS-FO. 90% of DS users seek at least one approval source of their DS and 50% support DS recommendation by doctors.

Conclusion

Favorableness towards DS is more prevalent among DS+FO. Most respondents lack knowledge about the legislative background of DS and many would agree to professional guidance.

Assessment of Nutrient Intake and Diet Quality in Adolescent Dietary Supplement Users vs. Non-Users: The CRO-PALS Longitudinal Study

Dietary supplement users tend to have a better diet quality and overall prudent lifestyle. The main goals of this research were to report the prevalence and type of dietary supplements among Croatian adolescents and to examine the differences in the diet quality among dietary supplement users vs. non-users at the beginning (15/16 y) and at the end of high school education (18/19 y). This research is based on results of the longitudinal CRO-PALS study in which 607 adolescents participated, who had complete dietary, anthropometric, and physical activity data at the beginning (15/16 y) and at the end of their high school education (18/19 y). The dietary assessment method used was a single multi-pass 24 h recall. Dietary supplement users were divided into two groups for the purposes of statistical analysis-users of vitamin and multivitamin preparations (VMV) and users of mineral and multivitamin preparations (MMV). As they aged, there was an increase in the consumption of dietary supplements, and the most frequently used preparation in both age groups was vitamin C (23.7% of users). Dietary supplement users had a higher intake of non-carbonated sweetened drinks and a lower intake of fruits and vegetables in both genders and both age groups. Fast food intake was higher among dietary supplement girl users and boys who were not dietary supplements users in both age groups. Dietary supplement users had a higher achieved average intake of most micronutrients (values obtained only from food) in both genders and both age groups (with exceptions for certain vitamins and minerals). By observing other parameters for assessing the diet quality in this research, we can conclude that girls who do not use dietary supplements have a better diet quality in both age groups.

Prevalence, Determinants, and Consumer Stance towards Dietary Supplements According to Sex in a Large Greek Sample: A Cross-Sectional Study

A stratified random sampling technique was used in order to explore the prevalence of and the factors influencing dietary supplement (DS) use and the consumer stance towards DS by Greeks (n = 28,491, ≥15 years) according to sex. Additionally, we performed a Pearson’s chi-square to test within DS users for the dependence between sex and the examined factors, and binary logistic regression to create predictive DS user profiles. A history of DS use accounted for 55.5% and was more prevalent in women (58.4% vs. 52.3%, p < 0.001); multivitamins were the most popular DS used. The significant predictors for DS use for both sexes were age, education, employment status, exercise, and following a special diet, while BMI and monthly income were significant for women and men, respectively. The women and men DS users had mostly illness-health and fitness-related goals, respectively. Substantial proportions of the respondents had false beliefs about DS. A noticeable percentage of DS users displayed imprudent behavior regarding DS use, e.g., one out of five did not know the definition or did not take into consideration the recommended daily allowance. While several factors seemed to impact DS use, with certain differences between the sexes, the considerable lack of knowledgeable and responsible use of DS, with few differences between the sexes, observed can point state authorities and health professionals towards appropriate countermeasures.

Dietary Supplements Use among Serbian Undergraduate Students of Different Academic Fields

The rising popularity of dietary supplements as a part of self-care practice increases interest in monitoring their usage in the general and specific population groups. This study investigated the prevalence and patterns of dietary supplement use among Belgrade University undergraduate students and its variations across different academic study fields. Of the 914 online survey students, 55.7% used dietary supplements during the past year. Female gender, eating behavior, and academic field were significant predictors of dietary supplement use. For all students, the most commonly used dietary supplements were vitamins and minerals, alone or in combination. Magnesium, vitamin C, and B vitamins were the most frequently supplemented micronutrients. The reasons for using, place of purchase, and source of information regarding dietary supplements significantly varied among students of different fields of study. Adverse effects related to dietary supplement use, including gastrointestinal symptoms, skin flushing, dizziness, and heart palpitation, were reported in 4.5% of students. Insufficient knowledge about these products was self-reported by 16.5% of users, more common among non-medical students. Thus, public health interventions are needed to improve students' knowledge regarding rational and safe dietary supplement use.

Dietary Supplement Use in Relation to Socio-Demographic and Lifestyle Factors, including Adherence to Mediterranean-Style Diet in University Students

The study aimed to examine socio-demographic and lifestyle determinants, including diet quality, of dietary supplement (DS) use among 2545 students who attended public universities in Warsaw. The data was collected using a self-administered health and lifestyle questionnaire and a 5-day dietary record method. Diet quality was assessed using a Mediterranean Diet Score. To determine the covariates of DS use, multivariate-adjusted logistic regression models with an estimation of odds ratios (ORs) and 95% confidence intervals (95% CIs) were used. The results showed that 41% of participants were DS users. The following predictors of DS use were identified: gender (male vs. female; OR:0.62, 95% CI:0.50–0.79), physical activity (high vs. low; OR:1.79, 95% CI:1.45–2.20), BMI (≥25 vs. 18.5–24.9 kg/m²; OR:0.77, 95% CI:0.61–0.98), cigarette smoking (yes vs. no; OR:0.67, 95% CI:0.52–0.86), and presence of chronic diseases (yes vs. no; OR:2.37, 95% CI:1.89–2.98). Moreover, higher nutritional knowledge, special diet usage, eating more meals/day, and fortified food consumption were determinants of DS use. Adherence to the Mediterranean-style diet was positively associated with DS use, a 1-score increment was associated with a 10% (p-trend = 0.011) higher probability of DS usage. Given that the use of vitamins and/or minerals is common among university students and their users are characterized by eating a higher quality diet, investigating the contribution of DS in overall dietary nutrient intake warrants further study.

Use of Dietary Supplements and Perceived Knowledge among Adults Living with Fibromyalgia in Norway: A Cross-Sectional Study

Fibromyalgia syndrome (FMS) is a complex medical condition characterized by widespread musculoskeletal pain. To date, no gold standard treatment has been developed, and persons with FMS often seek alternative methods to control their symptoms, such as dietary supplements (DS). This study aimed to describe the use of DS in persons living with FMS and examine the associations between the use of DS and its potential predictors. We recruited a convenience sample of 504 participants (≥18 years) living with FMS. The main outcome variables included estimated expenditure on DS in the last 12 months in Norwegian kroner (NOK) and the differences between the groups of users and non-users of DS. Of the 504 participants, 430 reported having used DS, and the mean amount of money spent in the previous year was determined to be NOK 2300. The most common DS reported were vitamin D, magnesium, and omega-3 fatty acids. The predictors of being a DS user were high education, high self-reported knowledge of DS but low overall knowledge of health claims. Users of DS marketed for muscles/joints appear to spend more money on DS. The increasing availability of DS and aggressive advertising in the media through health claims stipulate the need for interventions that lead to informed decisions about DS.

Nutritional implications of dietary gluten avoidance among Canadians: results from the 2015 Canadian Community Health Survey

Adherence to a gluten-free diet (GFD) is the only available treatment for gluten-related disorders, although a GFD may also be followed for discretionary reasons. The main objectives of the present study were to (1) describe and test for differences in key nutrient intakes among Canadians who follow a GFD compared with Canadians with no dietary exclusions and (2) describe additional dietary avoidances adhered to by Canadians who avoid gluten. We conducted a secondary analysis of the cross-sectional 2015 Canadian Community Health Survey-Nutrition Survey, which included a general health survey and 24-h dietary recall (n 20 487). Participants were categorised as those who avoid dietary gluten and those who reported no avoidances. Key nutrient intakes were assessed, as a percentage of Dietary Recommended Intakes, including fibre, B vitamins, vitamin D, Ca, Fe, Na and Zn, and compared between the two groups using t tests. Canadians who avoided gluten had significantly lower intakes of folate, vitamin B12, vitamin D, Fe, Na and Ca compared with those who did not avoid any food groups. However, Canadians who reported following a GFD were significantly more likely to use vitamin or mineral supplements in the past 30 d. More than 20 % of those who avoided gluten also avoided dairy products. Findings suggest that following a GFD places Canadians at risk for nutrient inadequacies, particularly folate, Ca and vitamin D. Further research is required to further examine how multiple dietary avoidances among those who avoid gluten may contribute to dietary inadequacies.

Self-Selection Bias: An Essential Design Consideration for Nutrition Trials in Healthy Populations

Many researchers have identified the issue of self-selection bias hindering the ability to detect nutrient effects in healthy populations. However, it appears that no effort has been made to mitigate this potential design flaw. By recruiting individuals on the basis of pre-trial dietary intake, the Memory and Attention Supplementation Trial aimed to capture a cohort of participants with a wide variety of dietary intake, thus increasing the likelihood of a diverse range of nutrient status. This perspective specifically examines the profile of these trial volunteers and in doing so, we present the first empirical evidence of self-selection bias when recruiting healthy volunteers for a randomized controlled trial of a nutrient-based supplement. These findings support the anecdotal proposal that traditional recruitment methods inherently attract trial volunteers who are vastly unrepresentative of the population and threatens the generalizability of this field of research. Alternative approaches to recruitment, including a-priori screening for baseline diet quality and nutrient status, are discussed as essential design recommendations to ensure accurate interpretation of nutrient effects within the context of baseline participant characteristics.

Dietary patterns according to vitamin supplement use. A cross-sectional study in Switzerland

Background: consumers of dietary supplements (DS) or vitamin-mineral supplements (VMS) have a better health profile than nonconsumers; whether this also applies to healthier dietary patterns has seldom been assessed. We aimed to assess the dietary intake of subjects according to their consumption of DS or VMS. Methods: Cross-sectional, population-based studies conducted in 2009-2012 (3773 participants, 52.4% women, 57.0 ± 10.0 years) and 2014-2017 (2536 participants, 52.4% women, 60.0 ± 10 years) in Lausanne, Switzerland. Dietary intake was assessed via a 97-item food frequency questionnaire. Nutrients, consumption of specific food groups, dietary scores, and compliance with the Swiss nutritional guidelines were compared between VMS/DS consumers and nonconsumers. Results: In 2009-2012, after multivariable adjustment for gender, age, body mass index, education, smoking, country of birth, sedentariness, diet and total energy intake, VMS/DS consumers had a higher score for the "Fruits & vegetables"(-0.09 ± 0.02 vs. 0.15 ± 0.05) dietary pattern and a lower score for the "Fatty & sugary" dietary pattern (0.02 ± 0.02 vs. -0.14 ± 0.04) and had a lower likelihood to comply with the guideline on total fat [odds ratio and 95 %CI: 0.72 (0.57-0.89)] than nonconsumers. In 2014-2017, after multivariable adjustment, no differences (at p < 0.005) were found between VMS/DS consumers and nonconsumers. Conclusion: VMS/DS consumers tend to have healthier dietary choices than nonconsumers. The beneficial effect of VMS and/or DS consumption is decreased, as it does not target subjects who really need them.

Healthy lifestyles among military active duty service members, and associations with body-building and weight-loss supplement use

PURPOSE

The purpose of this study was to characterize health behavior profiles among active duty service members and associate these profiles with body-building and weight-loss dietary supplement (DS) use.

METHODS

Based on U.S. active duty service members who completed the 2011 Health-Related Behavior Survey (n = 39,877), we used latent class analysis to place respondents into latent classes (using healthy/unhealthy food consumption, aerobic activity, strength training, and sleep) and examined associations between latent class and DS use.

RESULTS

We identified seven health behavior classes that could be classified by physical activity and diet. Three classes with high activity were further characterized by healthy diet (24%); few unhealthy foods (18%); and unrestricted diet (9%). Three classes with low activity were further characterized by restricted diet (15%), healthy diet (15%), and unhealthy diet (6%). The last class (13%) reported moderate levels of all behaviors. The classes did not vary by sleep. Participant characteristics across most classes were relatively homogenous along demographics and military branch. The active classes had relatively higher usage of body-building and weight-loss DSs.

CONCLUSIONS

Latent classes from health behavior indicators might be considered "market segments", which can be targeted with distinct messaging. Service members appear to consume DSs as part of an otherwise healthy lifestyle.

The Prevalence and Awareness Concerning Dietary Supplement Use among Saudi Adolescents

Current dietary supplement (DS) use among Saudi school students is not well described. In this study, we aim to investigate the prevalence and predictors of DS use among adolescents. This cross-sectional study collected data via self-administered questionnaire from 1221 students (12 to 18 years). The overall prevalence of DS use was 26.2%, significantly higher in females than males (33% vs. 17.9%, p < 0.001). High proportion of female DS users demonstrated normal BMI than males (84% vs. 56.5%, p < 0.001). High percentage of male DS users were engaged in vigorous and/or high physical activity (PA) levels than female DS users (58.2% vs. 43%, p = 0.022; and 57.1% vs. 20.7%, p < 0.001, respectively). The main reasons for DS use among females were vitamin deficiency (63.3%), hair condition (37.6%) and nail health (23.5%) while in males, the main reasons were vitamin deficiency (58.4%) and body building (34.4%). The predictors of DS use in Saudi adolescents included being female, having high family income and being physically active. In conclusion, the overall prevalence and preference of DS use, though low among Saudi adolescents, was driven mostly by gender, physical activity levels and socioeconomic factors like family income. DS use guidelines and counselling among Saudi adolescents are warranted to improve public health.

Vitamin Substitution Beyond Childhood—Requirements and Risks

BACKGROUND

Vitamins are vitally important, but they are not always adequately supplied with the diet. In this review, we present the advantages and disadvantages of vitamin supplementation and the indications for it in various life situations.

METHODS

This review is based on pertinent publications retrieved by a selective search of the literature.

RESULTS

The German National Nutrition Survey II (Nationale Verzehrsstudie II) showed that most people in Germany consume adequate amounts of vitamins in their diet, with the exception of vitamin D and folate. Supplements are often taken by adults who already consume a balanced diet. Depending on the vitamin, 3-13% of survey respondents took vitamin supplements; the ones most often taken were vitamins C and E. No convincing evidence has yet demonstrated a health benefit from vitamin supplementation in addition to a balanced diet for the primary prevention of nutrition-associated diseases. Vitamin supplementation is indicated in certain specific life situations, e.g., pregnancy, but otherwise unnecessary, unless a deficiency has been diagnosed or the individual is at elevated risk.

CONCLUSION

Vitamin supplementation is recommended for certain population groups: folic acid for pregnant women, vitamin B12 for vegans and persons with resorption disorders, vitamin D for persons with insufficient endogenous synthesis. In all other cases, it should first be tested whether the individual might be substantially helped by dietary changes alone. In general, the potential adverse effects of vitamin supplementation need to be considered, and its benefits weighed against its risks.

Concomitant Use of Dietary Supplements and Medicines among Preschool and School-Aged Children in Japan

Dietary supplement use is widespread amongst the general population including in children and adolescents. The ingredients in dietary supplements can interact with medicines when patients take them concomitantly. However, the prevalence of the concomitant use of dietary supplements and medicines in Japan among children remains unclear. To clarify this issue, a nationwide internet survey was administered to 55,038 mothers (25 to 60 years old) of preschool- or school-aged children in Japan. Among them, 7.6% currently provide dietary supplements and 3.2% concomitantly provide dietary supplements and prescription or over-the-counter medicines to their children. The prevalence of concomitant use increased with the children's grade. Among 1057 mothers with 1154 children who were concomitantly using dietary supplements and medicines, 69.1% provided dietary supplements without physician consultation because they considered dietary supplements as only foods and therefore safe. Although the purpose of the use and types of dietary supplement differed between boys and girls, the most popular product was probiotics in both boys and girls. Among concomitant users, 8.3% of mothers gave dietary supplements for treatment of diseases and 4.9% mothers recognized the adverse events of dietary supplements in their child. The findings of this study suggest that mothers' knowledge about the risk of using dietary supplement with medicines is insufficient. Parental education about the safety of dietary supplements and potential risk of drug-supplement interaction is needed.

Epidemiology of dietary supplement use in Serbia: Report from Novi Sad

OBJECTIVES

The primary objectives were to assess the prevalence of dietary supplement (DS) use and to identify specific demographic and lifestyle characteristics of DS users from Novi Sad, Serbia as well as the most commonly used DS and reasons for their use.

DESIGN

Observational, cross-sectional study.

SETTING AND INTERVENTIONS

Data on demographics, lifestyle and dietary supplement use of 435 adults from Novi Sad, Serbia were collected using an online questionnaire.

RESULTS

In total, 435 subjects completed the questionnaire (62.3% women). Prevalence of dietary supplement use in the sample was 42.8%. More women used DS than men (p = 0.002). Higher use of DS was reported among individuals 65+, while the young used DS less (p = 0.001), but the highest proportions of DS users was from the 45-54 age group. DS were used more among those with lower education levels (p < 0.001) and no income (p = 0.009). The highest percentages of DS users reported daily intakes of fruits and moderate physical activity, were non-smokers and social drinkers. Main reason for DS use was maintaining general health. The most commonly used DS were minerals and/or vitamins (68.8%).

CONCLUSIONS

We report a high prevalence of dietary supplement use in Novi Sad. DS use was associated with being a female, being older and having minimal/average income, the latter being opposite of the usual findings. Our results warrant a more detailed examination of the association between income, DS use and healthcare availability in developing countries such as Serbia.

Contaminants: a dark side of food supplements?

Food supplements (FS) are often consumed as one of the strategies to fight ageing-associated pathologies, especially in the case of oxidative stress-related diseases. Despite the popularity of FS, some concerns about their quality and safety have been raised, especially regarding the presence of contaminants. This paper reviews and discusses the occurrence of contaminants in marketed samples of FS in the last two decades, considering both scientific literature and notifications registered on RASFF portal. The most relevant classes of contaminants were included namely metals, toxins, pesticides, dioxins and PCBs, as well as pharmacologically active ingredients. Variable amounts of contaminants were reported in a significant number of commercially available FS. Although the presence of contaminants does not necessarily mean that their levels exceed the regulatory limits or that the FS intake constitutes a risk to human health, it alerts for the need to further monitor FS safety. The evaluation of the risk associated to the consumption of FS, especially in the elderly population, is particularly challenging due to the frequent exposure to multiple toxicants and to different exposure sources, as well as due to possible pre-existing diseases and respective therapeutics. Therefore, improved quality control procedures and monitoring programs should be pursued in order to avoid undesirable products and assure the safety of FS.

Knowledge Concerning Dietary Supplements among General Public

Introduction. Diet and physical activity are widely recognized in maintaining health and preventing diseases. Currently, dietary supplements are also commonly believed to play a role in health promotion. However, a dietary supplement lacks single uniform definition within the scope of legal or nutritional sciences. Data on the usage of dietary supplements in Europe are still limited. The aim of this study was to assess subjective and objective knowledge of the inhabitants of south-eastern Poland about diet and supplementation in sport. Materials and Methods. The research was conducted in the south-east of Poland between October 2017 and July 2018 during three events organized by the University of Rzeszów. Initially, the study covered 500 people. During the preliminary analysis, 90 people were excluded from the study because they did not meet the previously well-explained rules of conduct during the study or did not meet the eligibility criteria for the tests. Finally, 410 people were qualified for the study. The survey method was a questionnaire with single-answer option. Results. Our study revealed statistically significant subjective and objective level of knowledge about diet and supplementation in terms of sex. Also, a correlation was found between sex and the fact of being involved in physical activity, as well as the subjects' knowledge of diet and supplementation in sport. Conclusion. High prevalence of dietary supplement use was found in our study population, but still significant percentage of the study group demonstrate inaccurate information about these products. Hence, there is an urgent need to provide the community with education and access to scientific and unbiased information.

Use of vitamin and mineral supplements among adolescents living in Germany-Results from EsKiMo II

Dietary supplements may contribute to nutrient intake; however, actual data on dietary supplement use among adolescents living in Germany are rare. The aim of this analysis was to describe the current use of dietary supplements, its determinants, and reasons of use. Changes in supplement use over time were evaluated by comparing the results with those from EsKiMo I (2006). Data from the Eating Study as a KiGGS Module EsKiMo II (2015-2017) were used to analyze supplement intake according to sociodemographic, health characteristics, and physical exercise behavior of 12-17-year-olds (n = 1356). Supplement use during the past four weeks was assessed by a standardized computer assisted personal interview. Multivariable logistic regression was used to identify the association between supplement use and its determinants. Between 2015-2017, 16.4% (95%-CI: 13.0-19.7%) of the adolescents used dietary supplements, and its use decreased with lower levels of physical exercise and overweight. Most supplement users used only one supplement, often containing both vitamins and minerals. The most frequently supplemented nutrients were vitamin C and magnesium. The main reported reason to use supplements was 'to improve health'. Prevalence of supplement use was slightly lower in 2015-2017 than in 2006 (18.5%; 95%-CI: 15.8-21.2%). The results underline the importance of including nutrient intake through dietary supplements in nutrition surveys.

No association between vitamin C and E supplementation and grip strength over 5 years: the Colaus study

PURPOSE

To assess the cross-sectional and longitudinal association between self-reported vitamin C + E dietary supplementation and markers of grip strength and frailty in community-dwelling Swiss adults.

METHODS

Population-based study including 3277 participants (1722 women) aged 40-80 years at baseline. The associations between vitamin C + E dietary supplementation and grip strength were examined cross-sectionally and after a follow-up of 5.2 years on average.

RESULTS

There were 253 (7.7%) self-reported vitamin C + E supplement users. Female users had significantly lower grip strength than non-users (average ± standard deviation: 24.3 ± 6.1 versus 25.6 ± 6.1 kg, respectively). However, the association disappeared after multivariate adjustment (24.7 ± 0.5 versus 25.6 ± 0.1 kg, for users versus non-users, respectively). No differences were found in men regarding grip strength. No differences were found in the highest quintile of grip strength or prevalence of low grip strengthin in users versus non-users during cross-sectional analysis for both genders. After 5.2 years of follow-up, no associations were found between vitamin C + E supplementation and change in grip strength for raw values (difference between baseline and follow-up: 1.2 ± 5.0 versus 0.4 ± 5.2 kg for female and 0.6 ± 6.5 versus 1.1 ± 6.8 kg for male users and non-users, respectively) or after multivariable adjustment (1.2 ± 0.5 versus 0.4 ± 0.1 kg for female and 0.6 ± 0.8 versus 1.1 ± 0.2 kg for male users and non-users, respectively) when taking baseline vitamin C + E supplementation into account. No association was also found for incidence of low grip strength.

CONCLUSION

In a sample of community-dwelling Swiss adults, vitamin C + E supplementation neither improved grip strength nor prevented low-grip strength over a 5-year period.

Habits and beliefs related to food supplements: Results of a survey among Italian students of different education fields and levels

The increasing availability of food supplements, aggressive media advertising, and common beliefs that these substances have only positive effects on health and sport performance indicate a need for continuous monitoring of this phenomenon. The aim of this study was to investigate the habits and beliefs related to diet supplementation among medical, health professional, and other university/high school students by means of a cross-sectional anonymous survey online. Among the respondents aware of supplements, 37.4% were taking or had taken them in the past. Food supplement use was more common among university students (in particular, those in health professional graduate courses) than high school students. Individual sport practice, rather than team sport, was associated with higher likelihood of food supplement use. Multivitamins were most commonly used, while weight-loss formulations were the least popular. Strikingly, filling nutrient gaps was statistically not considered the main reason for taking food supplements. Instead, they were used to enhance mental performance or enhance well-being. There was statistical evidence that students not enrolled in health or medical professional studies strongly agreed more often than medical students that taking food supplements prevents illness. These results indicate a striking difference between the evidence-based and personal reasons for food supplement use. Arguably, it calls for an improvement in education about diet supplementation and a change in attitude of health care providers to its implementation.

Vitamin and Mineral Supplement Use among Korean Adults: Baseline Data from the Trace Element Study of Korean Adults in Yeungnam Area

Although dietary supplement use is believed to improve health status, the efficacy and safety of its use remains controversial. This study aimed to investigate the contribution of consumption of vitamin and mineral supplements (VMS) to the total micronutrient intake. Study participants (n = 586) were selected from the ongoing prospective cohort study of the Korean population, and baseline information on current use of dietary supplements, types of supplements, frequency of use, dosage, duration, and brand name was collected. Dietary information was assessed using a 146-item semi-quantitative food frequency questionnaire. Approximately one-fourth of the participants were categorized as VMS users. The proportion of VMS use was significantly higher in women (p = 0.02), older participants (p = 0.002), and those with a higher income level (p = 0.03) than in non-users. All vitamin and mineral intakes of both groups met the recommended nutrient intake levels by food consumption alone, except for riboflavin, calcium, and magnesium. Approximately 0.7-3.4% of the VMS users had nutrient intake levels that exceeded the tolerable upper intake levels for vitamin A, E, C, iron, and iodine. Excessive use of VMS can lead to an increased risk for adverse health effects. The results of this study provide useful baseline data for establishing guidelines for the appropriate consumption and adequate intake levels of VMS.