Very Low and Higher Carbohydrate Diets Promote Differential Appetite Responses in Adults with Type 2 Diabetes: A Randomized Trial.

BACKGROUND: Effects of very low carbohydrate (VLC) diets on appetite response in individuals with type 2 diabetes remain unclear.

OBJECTIVE: A secondary analysis was conducted to determine appetite responses to an energy-restricted [30% of energy (%E) deficit] very low carbohydrate (VLC) diet compared with a higher carbohydrate (HC) diet in adults who were overweight or obese with type 2 diabetes.

METHODS: Forty-four men and 40 women (mean ± SD, age: 58.7 ± 6.6 y; weight: 100.4 ± 15.5 kg; BMI: 34.5 ± 4.1 kg/m2; glycated hemoglobin: 7.3 ± 1.0%; duration of diabetes: 6.7 ± 5.6 y) were randomly assigned to diets categorized as VLC [14%E carbohydrate (<50 g/d), 28%E protein, 58%E fat (<10%E saturated fat)], or energy-matched HC [53%E carbohydrate, 17%E protein, 30%E fat (<10%E saturated fat)] combined with progressive multicomponent exercise (60 min; 3 d/wk). Body weight, average weekly "daily fasting" and "daily overall" appetite perceptions (hunger, fullness, prospective consumption, and desire to eat-visual analog scales) were assessed at baseline and after 4 and 16 wk. Changes between diets over time were assessed using repeated measures ANOVA.

RESULTS: Significant decreases in body weight did not differ between groups (VLC: -11.0 ± 5.4 kg/16 wk compared with HC: -10.1 ± 4.3 kg/16 wk, P = 0.40). There was no difference between diet groups in "daily fasting" appetite ratings (P ≥ 0.30) or "daily overall" hunger and desire to eat (P ≥ 0.21). Compared with HC, VLC had greater decreases in "daily overall" ratings of fullness at Week 4 (VLC: -6 ± 2 compared with HC: 1 ± 2 arbitrary units, P = 0.001) and Week 16 (VLC: -3 ± 1 compared with HC: 3 ± 2 arbitrary units, P = 0.019) and reduced prospective consumption ratings at Week 4 (VLC: 5 ± 1 compared with HC: 0 ± 1 arbitrary units, P = 0.008).

CONCLUSIONS: In the context of energy restriction, both HC and VLC energy-matched diets promoted comparable effects on fasting perceptions of appetite, but the HC diet resulted in greater "daily overall" fullness and reduced prospective consumption. Further research is required to evaluate the effects of ad libitum diets differing in amounts of carbohydrate on appetite response in populations with type 2 diabetes. This trial was registered at www.anzctr.org.au as ACTRN12612000369820.