Impact of Red Cabbage and Red Onion Anthocyanin Supplementation on Lipid Profiles in Amateur Soccer Players: A Randomized Placebo-Controlled Study

Background: Dietary anthocyanins have been recognized for their potent antioxidant and hypolipidemic properties. However, the efficacy of anthocyanin-rich dietary interventions in modulating the lipid metabolism of physically active cohorts remains unclear. Aims: This exploratory, placebo-controlled pilot study aimed to evaluate whether a short-term (22-day) dietary supplementation with anthocyanin-rich red cabbage juice or red onion salad significantly modulates lipid profile parameters, including low-density lipoprotein cholesterol (LDL-C), high-density lipoprotein cholesterol (HDL-C), total cholesterol (TC), and triglycerides (TG), in healthy amateur soccer players. Methods: Fifteen male amateur soccer players (mean age: 24.86 ± 5.93 years) were enrolled and randomly assigned to three groups: red cabbage, red onion, and placebo. Over a 22-day period, participants consumed their assigned supplement while maintaining their regular physical activity levels. Venous blood samples were collected via the cubital vein before baseline and post-intervention for lipid profile parameters. Statistical significance was assessed using paired t-tests and Analysis of Variance (ANOVA) or Welch’s ANOVA where appropriate, with the significance threshold set at p ≤ 0.05. Results: Intra-group analyses revealed no statistically significant amelioration in lipid parameters within the red cabbage or red onion cohorts. However, a significant elevation in LDL-C concentrations was observed in the placebo group, increasing from 0.63 ± 0.13 to 0.70 ± 0.11 g/L (p = 0.037). This observation likely reflects the influence of extraneous, uncontrolled variables rather than a direct consequence of the intervention. Conclusions: The findings indicate that short-term dietary supplementation with anthocyanins does not significantly alter the lipid profiles of amateur soccer players. This lack of physiological response may be attributable to the optimized lipid metabolism characteristic of physically active individuals or the exploratory nature of the study design. While these preliminary data provide a foundation for future, adequately powered investigations in athletic populations, the results should be interpreted with caution due to the limited sample size.