Obesity is classified by the World Health Organization (WHO) as a disease (ICD code=E66) and defined in terms of body mass index (BMI) in kg / m2, which is based on a combination of height and body weight. People with a BMI of 25–29.9 kg / m2 are defined as overweight and people with a BMI of 30 kg / m2 or more are defined as obese. The Irish diet generally tends to be higher in fat than the average European diet given the agricultural background, but in other respects is similar to other European countries. During the last 10 y, the number of obese people has increased substantially in Ireland with latest estimates suggesting a prevalence of between 13 and 18%.1, 2 It has been shown that obese people run a greater risk than people of normal weight of developing secondary diseases (eg type 2 diabetes (T2DM),3, 4 high blood pressure and cardiovascular disease5) and thus also an increased risk of early death.6 Obese patients are almost 28 times more likely to develop T2DM, compared with nonobese individuals.7 Obesity also has a negative effect on quality of life both physically and psychologically.8