(P20-023-25) Effects of Fresh Watermelon Consumption on TMAO and Cardiovascular Risk Markers in Adults With Overweight and Obesity

Objectives: Elevated trimethylamine N-oxide (TMAO) levels are associated with higher risk of cardiovascular disease (CVD). Watermelon consumption impacts cardiovascular function by improving lipid markers and promoting healthy endothelial function. No study has evaluated the effects of fresh watermelon consumption on TMAO levels. This study aims to assess the effects of watermelon on the cardiovascular risk markers including lipid profiles, inflammatory markers and TMAO levels in adults with overweight and obesity.

Methods: This 4-week crossover clinical trial enrolled 32 participants (16 men, 16 women), aged 18-50 years, with a BMI between 25-40kg/m². Participants consumed 330g of fresh watermelon (100 kcal) or isocaloric control, low-fat cookies for 4 weeks, with a 4-week washout period between interventions. Fasting blood draws were conducted at each visit. Data were analyzed using repeated measures ANOVA and paired t-tests at P=0.05.

Results: Results showed a significant decrease in TMAO levels post watermelon intervention (P=0.005). Levels of TMAO exhibited a lower trend post watermelon intervention compared to post cookie intervention (P=0.091). An increased trend in TMAO levels was observed post cookie intervention (P=0.063). Regarding lipid profiles, triglycerides and LDL cholesterol were significantly lower post watermelon intervention (P < 0.05). A trend toward lower total cholesterol (P=0.063) and higher HDL cholesterol (P=0.061) was found post watermelon intervention. An increased trend in C-reactive protein was observed after the cookie intervention (P=0.055). Total antioxidant capacity (TAC) increased after four weeks of watermelon consumption compared to four weeks of cookie consumption (P=0.022).

Conclusions: This reduction in lipid markers, along with the decrease in TMAO, highlights watermelon as a promising dietary intervention to mitigate obesity-related cardiovascular risk factors.

Funding Sources: National Watermelon Promotion Board (DTD 11-03-23)