Effect of Nutritional Supplements on Biochemical Parameters in Gym-Goers

Introduction

Introduction The World Health Organization (WHO) defines health and wellbeing as the state of complete physical, mental, and social well-being as opposed to only the absence of sickness or disability.¹ ‘Young adults’ refers to individuals aged 18 to 26 years.² This generation is among most health-conscious, particularly regarding diet and physical activity. This age group primarily includes college students and young professionals who are conscious of their appearance and body. In pursuit of these goals, many engage in gym workouts and rely on nutritional supplements to meet the nutritional needs and build muscle mass, especially among males.

Nutritional supplements are heavily advertised as muscle-building and performance-enhancing goods for athletes and physically active individuals. Protein, amino acid, and creatine supplements are commonly consumed by frequent gym-goers, often in combination with protein-rich meals and without professional nutritional guidance. It has been suggested in the literature that the nutritional needs of people with active lifestyle do not differ from those recommended for the average adult population, since the effort of regular gym-goers seldom approaches that of professional athletes.^3,4 Furthermore, some evidence indicates that nutritional supplements may have detrimental effects on general metabolic health, with the kidneys and liver being the primary organs affected.⁵

This study was designed to compare routine laboratory parameters between gym-goers who use dietary supplements and those who do not use any supplements.

Materials and Methods

The present study was conducted on 50 apparently healthy young adult male volunteers (18-26 years) who were regular gym-goers, defined as attending the gym at least three times per week for the past three months. Persons with any underlying chronic illness, a history of chronic smoking or alcohol use, or those taking any drugs or substances were excluded from the study. After obtaining informed consent and approval from the institutional ethical committee, participants underwent a detailed assessment, including their gym workout and the use of any supplements. Height, weight, body mass index (BMI), bp and pulse rate were measured and recorded.

Body weight was measured using a calibrated weighing scale with a precision of ± 5 g. Subjects were instructed to stand upright on the scale without shoes and wearing minimal clothing to minimize measurement error. A calibrated stadiometer was used for measuring the height. Subjects were asked to stand in an erect posture with their head, shoulder blades, buttocks and heels in contact with the stadiometer, and shoes were removed prior to measurement. BMI was calculated using the following standard formula: BMI (Kg/m² ) = Weight / Height² For blood pressure measurement, participants were seated and allowed to relax for five minutes with their arms bare and supported at heart level. A mercury sphygmomanometer was used to measure blood pressure from the left arm.

Subjects were instructed to fast overnight for at least eight hours. Fasting blood samples were drawn under aseptic conditions from the antecubital vein of each participant and analyzed for routine biochemistry, including renal function tests (RFTs), liver function tests (LFTs), lipid profile, fasting blood glucose (FBG), and complete blood count (CBC) using automated analyzers.

The collected data were compiled and subjected to statistical analysis.

Results

Results The mean age of the participating volunteers was 21±0.5 years, with ages ranging from 18 to 26 years. Among the 50 participants, 46 were students (29 undergraduate and 17 postgraduate), while four were working in private sector. Of the total participants, 30 were vegetarians and 20 non-vegetarians. The use of dietary supplements varied among individuals, with whey protein being the most commonly consumed. The duration of supplements ranged from 3 months to 3 years. The dose consumed varied between 1-3 scoops (~25 g) per day with either milk or plain water. Additionally, most of the participants (n=22) were consuming creatine supplements [1-2 scoops (~5 g) daily]. The work-out schedule varied among participants with durations ranging between 5-10 hours per week. The BMI of volunteers using dietary supplements was 25.09 ± 3.02 - kg/m², compared to 22.517 ± 1.91 - kg/m² in those not using any supplements. The difference was statistically significant with a P value < 0.001. A comparison of biochemical parameters between the two groups is presented in Table 1, and CBC findings are summarized in Table 2.

Discussion

The BMI of gym-goers using dietary supplements was found to be statistically higher compared to those not using any supplements (P<0.001). Regular gym visitors often use proteins and amino acids along with creatine supplements. These supplements are often taken in addition to other high protein meals, with no advice from dieticians, professional nutritionists, or doctors. The fitness or exercise level of typical gym attendees seldom matches that of professional athletes; therefore, their protein needs generally do not exceed the recommended intake levels established for the general adult population.^6,7 These supplements tend to increase body weight. An increase in BMI has also been reported in studies comparing vegetarians and omnivores, with the latter group consuming higher amounts of protein and exhibiting higher BMI values.⁸ Serum uric acid levels were also found significantly high in the group using protein supplements as compared to those not consuming any (P <0.01). Serum uric acid levels tend to reflect current dietary habits. Uric acid is the catabolic product of purines, hence consuming purine-rich foods adds to the overall levels of uric acid. High protein dietary supplements often include substantial amounts of purine and hence may contribute to increased uric acid levels in blood.⁹ Hyperuricemia has also been found to be associated with physical activity. However, it remains unclear whether this is due to decreased renal excretion or other underlying etiological factors.¹⁰ Alcohol is known to induce hyperuricemia; however, all the subjects in the present study were health-conscious individuals who abstained from alcohol and smoking. Dairy products in diet have been observed to have a uricosuric effect, particularly milk proteins such as casein and lactalbumin, which may contribute to low serum uric acid levels.¹¹ The intake of dairy products was not specifically accounted for in this study, as young adults in Haryana typically consume substantial amounts of milk and milk products as part of their regular diet. It is likely that diary consumption was even higher among gymgoers not using commercial supplements, in an attempt to meet increased energy demand and to compensate for commercial supplements. This difference in dietary habits could potentially explain the variation in serum uric acid levels observed between the two groups.

Serum phosphorus levels were found to be significantly decreased in the gym goers consuming protein supplements as compared to those not using any supplements (P=0.006). Phosphorus content of protein supplements is high which may induce the release of fibroblast growth factor 23 (FGF 23) derived from bones. FGF 23 stimulates phosphorus excretion through the kidneys and its increased release may have an association with low phosphorus levels in serum.¹² Higher phosphate concentrations also suppress vitamin D activation and stimulate parathyroid hormone (PTH) release. Vitamin D increases phosphorus reabsorption in renal tubules while PTH promotes the excretion of phosphorus through renal tubules.¹³ This may explain the low phosphorus levels observed with the use of protein supplements.

In lipid profile, total cholesterol and low-density lipoprotein-cholesterol (LDL-C) were found to be significantly reduced in study participants using dietary supplements compared to those not using any supplements (P <0.05). Dietary supplements, especially whey protein, have been shown to have a positive influence on lipid metabolism. It is proposed that the functional components found in these supplements, such as sphingolipids and beta-lactoglobulin, restrict cholesterol absorption in the colon. Other mechanisms put forward include activation of lipoprotein lipase, down-regulation of expression of proteins involved in cholesterol absorption and fatty acid transport, brought about by the branched chain amino acid content of protein supplements.^14,15 Furthermore, the calcium component of dietary supplements may cause calcium-fatty acid soap formation in the gastrointestinal tract, resulting in less fat absorption. Various proteins from different sources and properties may have distinct metabolic effects in this respect.^16,17 Therefore, dietary supplements can have diverse effects on the metabolism. The differences in other components of renal function tests, CBC and additional biochemical parameters were not found to be statistically significant, likely due to the small sample size in this study. These findings highlight the need for further research involving a larger sample size, with detailed consideration of supplement-related attributes such as dose, type and duration and inclusion of broader range of physiological and biochemical parameters.

Conclusion

Conclusion The present study highlights significant physiological and biochemical differences between gym-goers who use dietary supplements and those who do not. Notably, supplement users exhibited a higher BMI and elevated serum uric acid levels, likely influenced by increased intake of purine-rich protein supplements without professional dietary guidance. Additionally, a significant reduction in serum phosphorus levels among supplement users suggests a potential impact of high phosphorus intake on mineral metabolism. Conversely, favorable changes in lipid profile specifically reductions in total cholesterol and LDL-C indicate potential cardiometabolic benefits of certain protein supplements, particularly those containing whey. These findings underscore the complex effects of dietary supplements on health and metabolism, emphasizing the importance of individualized nutritional assessment and the need for larger-scale studies to further explore these associations, accounting for supplement composition, dosage, duration of use, and broader lifestyle factors.

Conflict of Interest

None

Acknowledgements

The contribution of Mr. Prashant, technician, Biochemistry department and gym owners Mr. Satish Punia, Mr. Sandeep Punia and Mr. Charan Singh is deeply acknowledged.