Posted on Tue, 12 Nov 13
Intermittent fasting is gaining popularity as a weight loss strategy and a new clinical study found impressive effects within just 12 weeks.
Intermittent or alternate day fasting involves a reduced calorie intake balanced with unrestricted eating on alternate days. A popular approach is the 5:2 strategy which adheres to 2 low calorie days per week based on low energy density foods such as whole grains, vegetables, fruits and lean meats.
Despite its popularity only a few studies have explored the effects of this dietary approach. In a new study 32 people were randomized to either an intermittent fasting diet (FAST diet) or a control diet for 12 weeks. The FAST diet group consumed 25% of their baseline energy needs on the fast day (24 h), and then ate freely on each alternating day.
After 12-weeks the FAST diet resulted in a reduction in body weight of an average 5.2 kg and a reduction in fat mass of 3.6 kg (see figure 1).
Figure 1: Changes in body composition with alternate day fasting (ADF) versus control.
The FAST diet also significantly reduced triglycerides, inflammation (C-reactive protein) and favourably influenced other metabolic risk markers (LDL particle size, plasma adiponectin, and leptin).
“In summary, these preliminary findings suggest that ADF is a viable weight loss strategy for normal weight and overweight individuals wishing to lose a moderate amount of weight (5–6 kg) within a relatively short period of time (12 weeks)” concluded the study investigators. “It is our hope that this preliminary data will be utilized to design larger-scale longer-term trials with similar objectives, in normal weight and overweight participants undergoing ADF.”
Varady KA, Bhutani S, Klempel MC, Kroeger CM, Trepanowski JF, Haus JM, Hoddy KK, Calvo Y. Alternate day fasting for weight loss in normal weight and overweight subjects: a randomized controlled trial. Nutr J. 2013 Nov 12;12(1):146. [Epub ahead of print]