Comparison of a low-energy diet and a very low-energy diet in sedentary obese individuals: a pragmatic randomized controlled trial


P. Christensen et al. Denmark


Clinical Obesity (2011) 1758-8111


The purpose of the study was to compare a period with a VLED diet (very low energy diet) with an LED diet (low energy diet) among older obese persons suffering from osteoarthritis in their knees.

Patient Group:

175 patients with obesity (BMI >30 kg/m2) and confirmed osteoarthritis over the age of 50. The average weight upon the beginning of treatment was 103.2 kg with a BMI of 37.3 kg/m2 and a waist circumference of 111.4 cm.


The participants were randomised into two different groups, where one group received LED (810 kcal) and the other group received VLED (415-552 kcal) for an eight-week period. They met a dietician on a weekly basis in order to be weighed and to receive information about the food. Following these eight weeks, a further eight-week period was begun in which all participants, regardless of previous diets, ate a diet that included two meal replacements per day, providing a total of 1200 kcal.

Results and discussion:

After the first eight weeks of treatment, the average weight loss in the VLED group was 11.4 kg, and 10.7 kg in the group that received LED, which did not demonstrate any significant difference. The weight loss after 16 weeks was 13.3 kg in the VLED group, and 12.2 kg in the LED group, and there was no significant difference between the groups.

Upon measuring body composition (determined via DEXA). It was shown that the VLED group had lost 2.1 kg of fat-free mass, while the LED group had lost 1.2 kg. The difference between the groups was significant. The fat mass was reduced by 10.3 kg in the VLED group, and 8.9 kg in the LED group, which did not demonstrate any significance.

The most commonly reported side effects during treatment were bad breath, feeling cold and increased flatulence. After 16 weeks, the only side effect with a significant difference between the groups was abdominal pain (VLED 12.5 % vs LED 4.2 %).

The most important finding of the study was that there was no difference in weight loss between the groups and that there was no weight loss advantage in using the VLED diet, which provides 415 to 554 kcal, in comparison with 810 kcal. The protein content in the LED diet was 83.9 g, and between 43.2 and 57.6 g in the VLED diet, which may have contributed to the weight loss in this group. The group receiving the VLED diet lost 17% of fat-free mass, while the LED group lost 11% of fat-free mass, which may be explained by the LED group having had a higher energy and protein intake.


Both the LED and the VLED diets were effective treatments in achieving weight loss, improving blood pressure, reducing waist circumference and improving blood variables in older individuals with obesity. The significantly lower reduction of fat-free mass in the group having received the LED diet as opposed to the higher frequency of reported side effects (bad breath, intolerance to call and flatulence) in the group having received the VLED diet, suggests that LED should be the primary choice in the treatment of obesity.…