A Dunedin-based RCT (Coppell et al 2010) compared usual care with usual care plus intensive individualised dietary advice over a six-month period. There were 93 participants aged less than 70 with type 2 diabetes, HbA1c greater than 53 mmol/mol despite optimal drug treatment, and at least two of overweight or obesity, hypertension and dyslipidaemia. After adjusting for age, sex, and baseline measurements, the difference in HbA1c between the intervention and control groups at six months was highly statistically significant as were decreases in BMI and waist measurement. A decrease in saturated fat and an increase in protein in the intervention group were the most striking differences in nutritional intake between the two groups.
