The survey, published in 'Nutrients', was completed by 117 footballers (79 males and 38 females) recruited from a range of top leagues in Turkey.
Results reveal the prevalence of dietary supplement (DS) use was 87.2% of the total participants (males: 93.7%; females: 73.7%) and significant relationships were found between DS use and sex as well as competition levels but not the education level of footballers.
The most consumed DS were sports drinks (63.2%), magnesium (52.1%), vitamin C (51.3%), vitamin D (46.2%), caffeine (38.5%), sports bars (37.6%), whey protein (28.2%), meat protein (25.6%), vitamin E (24.8%), and omega-3 fatty acids (24.8%).
Within the survey, the type of DS ingested was classified based on the level of scientific evidence by the Australian Institute of Sport (AIS): group A (high level of scientific evidence), group B (DS that could have a positive effect, but require more evidence), group C (evidence is against their use), and group D (prohibited substances).
The researchers note the unexpectedly high consumption of magnesium, which belongs to group C - evidence is against their use. The researchers note consumption is probably due to the fact that this mineral is an essential mineral involved in energy metabolism, cardiorespiratory function, and muscle actions with potential benefit for improved performance parameters in exercise.
Male vs female
Males reported higher consumption of sports gels, electrolytes, whey protein, meat protein, multivitamin complex, caffeine, creatine monohydrate, omega-3 fatty acids, BCAA, and vitamin E than female footballers.
The researchers note that this may be linked to the fact the number of weekly training sessions was significantly higher for male footballers, due to requirements in male football leagues.
The report states: "The developmental process of female football is already at an early stage in Turkey. Female footballers are considered amateurs even if they play in professional/top leagues. The level of female football is not at the desired level financially, culturally, and in terms of performance compared to the international arena. Therefore, there are expected differences in sports activity according to sex."
Other supplements such as vitamin D were taken by a similar share of males and females. This may be due to the benefit the vitamin is said to have on bone health as well as immune and general health, which are appealing benefits for both sexes. Bone health could potentially be considered more of a concern for females as bone health can deteriorate during menopause.
Unsurprisingly, another effector which influenced the level of consumption of DS was competition level. Professional football players presented higher consumption of sports gels, electrolytes, whey protein, multivitamin complex, creatine monohydrate, omega-3 fatty acids, and BCAA compared to non-professionals.
Places of purchase
The survey report discusses the places where footballers are likely to get their DS. It notes that Oliveira et al. reported that the most frequent places of DS purchase by elite female football players were stores (30.0%), through sponsorships (26.0%), and pharmacies/drugstores (22.0%).
In the present study, the most frequent places of DS purchase were football clubs (26.3%), pharmacies (17.5%), and the internet (13.5%).
The researchers suggest the reason that pharmacies are one of the main places to purchase DS in these two studies may be related to the fact that the supplements generally preferred by football players are from the medical supplement class. On the other hand, the report notes the relationship between the level of competition and supplements provided by the club may be due to the economic power and sponsorship of the clubs playing in the higher leagues.
Concerning the main source of information to determine the type, use, and utility of DS, the present study shows dietitians/nutritionists as the major motivators of DS consumption (29.7%).
The team behind the survey say this result is important because athletes who receive advice from a dietitian/nutritionist as the main source of nutritional information have better eating habits, a higher understanding of nutrient periodization, and consumption of DS with a high level of scientific evidence. This finding could be related to male professional football clubs having different supplementation programs planned by the club’s dietitian.
Self-encouragement (20.0%) was another significant determinant in motivation for DS consumption.
Some limitations of this study include the limited number of volunteers, the sample being heterogeneous in relation to the sex of footballers and the lack of data about the DS consumption of Turkish male amateur league footballers. In the future, large, comprehensive studies that include all these categories are required to increase sports performance and thus protect and improve the health of all Turkish footballers.
"Dietary Supplement Use of Turkish Footballers: Differences by Sex and Competition Level"
Günalan, E.; Çavak, B.Y.; Turhan, S.; Cebio ˘glu, ˙I.K.; Domínguez, R.; Sánchez-Oliver, A.J.