Association of nutritional knowledge and supplement intake among gym goers in Puncak alam, Selangor

The rise in dietary supplement use among gym-goers has become a growing public health interest, particularly given the increasing influence of social media, marketing, and peer- driven information. This study aimed to investigate the association between nutritional knowledge and supplement intake among gym-goers in Puncak Alam, Selangor. Employing a cross-sectional design, 148 participants from six local gymnasiums were recruited through convenience sampling. Data were collected via validated self- administered questionnaires assessing socio-demographics, nutritional knowledge, supplement consumption patterns, and perceptions of dietary supplements. Results revealed that while 80.4% of participants reported consuming at least one dietary supplement, only 37.8% demonstrated high nutritional knowledge. Multivitamins, vitamin C, and protein-based products were among the most commonly consumed supplements. The primary motivations for use included general health maintenance, muscle gain, and physical performance enhancement. Despite these patterns, statistical analyses—including Spearman’s correlation and Mann–Whitney U tests—demonstrated no significant relationship between nutritional knowledge and the number of supplements consumed (p > 0.05), highlighting a notable knowledge-practice gap. Many respondents relied on non-professional sources such as social media, peers, and online platforms for supplement information, rather than consulting healthcare professionals. These findings underscore a critical disconnect between knowledge and behavior, where supplement use appears largely influenced by external perceptions rather than evidence-based understanding. The study recommends targeted educational interventions to bridge this gap, improve nutritional literacy, and promote safe, informed supplement practices among fitness enthusiasts. Such efforts are crucial for minimizing health risks and fostering a more responsible supplement culture within Malaysia’s gym-going population.