Obesity—defined as a body mass index greater than 30 or a waist measurement in excess of 40 inches in a woman and 50 in a man—has been classified, as a disease process by numerous scientific circles. According to “Effect of Weight Loss via Severe vs Moderate Energy Restriction on Lean Mass and Body Composition Among Postmenopausal Women with Obesity,” which appeared in the October 10, 2019, issue of JAMA Network Open, “effective obesity treatments are needed to reduce obesity-related morbidities and costs.”
Current research states that “the most effective dietary obesity treatments are severely energy-restricted diets of less than 800 kcal/day, which often involve replacing all or almost all foods with nutritionally replete meal replacement products (shakes, soups, or bars).”
One issue, especially in women, is the potential for bone loss during severe energy-restricted dieting, according to the study researchers from Australia. In addition, severe energy-restriction may also cause the potential for lean mass loss compared with moderate energy-restriction.
The Australian researchers designed The Type of Energy Manipulation for Promoting Optimum Metabolic Health and Body Composition in Obesity (TEMPO) Diet Trial – a 12-month, single-center, randomized clinical trial – that incorporated, “a total of 101 postmenopausal women, aged 45 to 65 years with body mass index (calculated as weight in kilograms divided by height in meters squared) from 30 to 40, who were at least 5 years after menopause, had fewer than 3 hours of structured physical activity per week.”
The intervention included participants, who were randomized to either12-months of moderate (25%-35%) energy restriction with a food-based diet (moderate intervention), or 4 months of severe (65%-75%) energy restriction with a total meal replacement diet followed by moderate energy restriction for an additional 8 months (severe intervention). Both interventions, note the researchers had a prescribed protein intake of 1.0 g/kg of actual body weight per day, and physical activity was encouraged but not supervised.
It was concluded that, “severe energy restriction had no greater adverse effect on relative whole-body lean mass or handgrip strength compared with moderate energy restriction and was associated with 2-fold greater weight and fat loss over 12 months.”
However, “there was significantly greater loss of total hip bone mineral density with severe vs moderate energy restriction. Therefore, caution is necessary when implementing severe energy restriction in postmenopausal women, particularly those with osteopenia or osteoporosis.”