Weight loss is crucial for treating type 2 diabetes mellitus (T2DM). It remains unclear which dietary intervention is best for optimising glycaemic control, or whether weight loss itself is the main reason behind observed improvements. The objective of this study was to assess the effects of various dietary interventions on glycaemic control in overweight and obese adults with T2DM when controlling for weight loss between dietary interventions. A systematic review of randomised controlled trials (RCT) was conducted. Electronic searches of Medline, Embase, Cinahl and Web of Science databases were conducted. Inclusion criteria included RCT with minimum 6 months duration, with participants having BMI≥25·0 kg/m², a diagnosis of T2DM using HbA1c, and no statistically significant difference in mean weight loss at the end point of intervention between dietary arms. Results showed that eleven studies met the inclusion criteria. Only four RCT indicated the benefit of a particular dietary intervention over another in improving HbA1c levels, including the Mediterranean, vegan and low glycaemic index (GI) diets. However the findings from one of the four studies showing a significant benefit are questionable because of failure to control for diabetes medications and poor adherence to the prescribed diets. In conclusion there is currently insufficient evidence to suggest that any particular diet is superior in treating overweight and obese patients with T2DM. Although the Mediterranean, vegan and low-GI diets appear to be promising, further research that controls for weight loss and the effects of diabetes medications in larger samples is needed.

Objective: It is widely recognised that South Asian men living in the UK are more likely to develop type 2 diabetes mellitus (T2DM) than their white British counterparts. Despite this, limited data have been published quantifying current dietary intake patterns and qualitatively exploring eating behaviours in this population. The objectives of this study were to (1) assess diet, (2) explore perceptions of T2DM, (3) investigate factors influencing eating behaviours in overweight/obese South Asian men and (4) determine the suitability of the UK Diet and Diabetes Questionnaire (UKDDQ) for use in this population.Setting: Community-based setting in the Greater London, UK area.Participants: South Asian men aged 18–64 years, with a body mass index of over 23.0 kg/m², not previously diagnosed with T2DM.Methods: A cross-sectional mixed-methods design, including assessment of dietary intake using UKDDQ (n=63), followed by semistructured interviews in a purposive sample (n=36).Results: UKDDQ scores indicated 54% of participants had a ‘healthy’ diet with a mean sample score of 3.44±0.43 out of a maximum of 5. Oily fish consumption was low (1.84±1.85). Body weight was positively associated with a high-added sugar subscore (r=0.253, p=0.047), with 69.8% of the men having ‘unhealthy’ intakes of sugar-sweetened beverages. Cultural commitments (eg, extended family and faith events), motivation and time were identified as key barriers to dietary change, with family support an important facilitator to making healthy dietary changes. Participants stated that UKDDQ was suitable for assessing diets of South Asians and made suggestions for tailoring questions related to rice consumption, providing examples of Indian sweets, and including ghee as a fat source.Conclusion: Many of the areas of dietary improvement and factors affecting eating behaviours identified in this study are similar to those observed in the general UK population. Consumption of sugar-sweetened beverages in particular was high; given the association between their consumption and the risk of T2DM, this should be an area of primary focus for healthcare professionals. Nevertheless, there are sociocultural factors unique to this population that need to be considered when designing culturally specific programs to reduce the development of T2DM in this high-risk population.

South Asian men living in the UK have higher rates of central obesity and Type 2 Diabetes Mellitus (T2DM) compared with their white British counterparts. Physical activity (PA) and sedentary time (ST) are important risk factors for the development of T2DM. The purpose of this study was to objectively measure PA, ST, and to explore the factors influencing these behaviours in this high-risk population. A mixed-methods cross-sectional research design was employed, including the quantification of PA and ST using the self-report International Physical Activity Questionnaire (IPAQ)-long form and accelerometry in overweight and obese UK South Asian men (n = 54), followed by semi-structured interviews in a purposive sub-sample to explore the factors influencing PA and ST (n = 31). Accelerometer-derived moderate-to-vigorous PA (MVPA) and ST were 298.9 ± 186.6 min/week and 551.4 ± 95.0 min/day, respectively. IPAQ-derived MVPA was significantly lower than accelerometer-derived MVPA (p < 0.001). IPAQ-derived ST was significantly higher than accelerometer-derived ST (p < 0.001). Lack of time and family commitments were identified as the main barriers to being more physically active, with group exercise identified as an important facilitator to being more active. A cultural norm of focusing on promoting education over sport participation during childhood was identified as an important factor influencing long-term PA behaviours. Work commitments and predominantly sedentary jobs were identified as the main barriers to reducing ST. Healthcare professionals and researchers need to consider the socio-cultural factors which affect PA engagement in overweight and obese South Asian men living in the UK, to ensure that advice and future interventions are tailored to address the needs of this population.