Background: As recent studies have shown that obesity has been associated with poor performances in executive function (EF) tasks. Working memory (WM) is one of the core component of the EFs which is essential for the goal directed behaviours. Therefore, the study was conducted to assess the association between obesity and WM tasks in a sample of 231 young adults aged 21–25 years in Colombo District, Sri Lanka.

Method: Body mass index (BMI) and Waist to hip ratio (WHR) were calculated for estimating generalized and central obesity respectively, while Body fat percentage (BF%) was estimated through sum of three site of skin fold thickness. WM were assessed via computerized WM tasks: visuospatial (VSWM) and verbal working memory (VWM) tasks.

Results: A significant group effect was observed among BMI groups (normal, overweight and obese) and the performances in WM tasks (F [4,454] = 10.1, p<0.001). Mean scores in VSWM and VWM scores were significantly lower amongst and when compared with normal BMI subjects (p<0.001).  Similarly, a significant lower mean scores in VSWM and VWM were observed in both male and female WHR categories when compared to their normal WHR subjects (p<0.05). A significant negative correlation was observed between VSWM scores and VWM scores with BF% for males and females (p<0.05).

Conclusions: Young adults in the study sample who were obese/overweight and had high WHR & high BF% were performed poorly in WM when compared with normal BMI and normal WHR & BF% categories.