Wen Yuan Lin, M.D., M.S., Chih Hsing Wu, M.D., Nain Feng Chu, M.D., Ph.D. and Chih Jen Chang, M.D.
Nutrition 25 (2009) 1129-1136
132 patients age 18-65 years with BMI > or =30kg/m2 were randomized to two diet replacement groups for a 12-week weight loss program. Each group had 66 participants.
Since traditional low-calorie diets usually produced marginal results among obese or severely obese patients, VLCDs with 800 kcal or less per day were developed. Lower calorie intake was expected to lead to greater weight loss, but previous studies have shown no significant difference in weight loss between products containing 240 kcal and 800 kcal per day.
Overweight and obesity are a growing problem in Taiwan, especially among children and men. Furthermore, obesity-related problems have been shown to affect Asians at lower BMI levels than other light-skinned peoples. They have a higher percentage of body fat at any given BMI.
After a two-week induction period during which a low-calorie diet containing 1200 kcal per day was introduced, patients were randomized to a VLCD group given 450 kcal per day or a group given 800 kcal (LCD), each for 12 weeks.
Parameters such as height, weight, waist circumference and hip circumference were measured at the first visit. An ultrasound examination was carried out both at screening and after 12 weeks of treatment. Resting Metabolic Rate (RMR) was also measured at baseline and after 12 weeks of diet replacement treatment.
Results and discussion:
Both treatment groups demonstrated significant (p < 0.001) weight loss of 9.14% and 8.98% respectively. No statistically significant difference between groups was measured. The reductions in waist circumference for the two groups were 8.87% and 9.12%, respectively, and reductions of hip circumference 6.08% and 6.51%, respectively. These differences between groups were not statistically significant, either.
After 12 weeks of treatment the percentage change in body fat over the treatment period was 10.5% in the 450 kcal group and 13.1% in the 800 kcal group. This difference between groups was not statistically significant.
The reduction in the proportion of lean body mass was not statistically significant in the 800-kcal group, while some loss of lean body mass was measured in the 450-kcal group. RMR had dropped by 109 kcal/day in the 450-kcal group after the treatment period. The corresponding figure for the 800-kcal group was 58.5 kcal/day. These differences in lean body mass and RMR between the groups were not statistically significant. The degree of improvement for nonalcoholic fatty liver disease (NAFLD) was 41.5% and 50.0% respectively in the two groups.
The study shows that both the 450 and 800 kcal per day formulations are safe and effective tools for treatment of obesity.
The results indicate that there is no advantage to using a diet replacement containing less than 800 kcal per day.
The results also show that 42.4% of all participants lost more than 10% of their weight over the 12-week treatment period. Fasting blood sugar, triglycerides and blood pressure also improved significantly after the treatment period. The 800-kcal group also achieved a statistically significant decrease in total cholesterol and LDL cholesterol after the treatment period.
Both 450 kcal and 800 kcal per day are safe and effective tools for achieving weight loss among obese Taiwanese people, but recommending a diet more restrictive than 800 kcal per day provides no additional advantage.