A 5 – 10% reduction in weight improves blood pressure, circulating cytokines, fasting levels of glucose, triglycerides and HDL cholesterol. A change in treatment regimen should be considered if weight loss is less than 5% in the first 6 months.
The proposed target is that a patient should regain less than 3kg of the weight lost over 3 years.
Lifestyle modification as an isolated tool for weight management has a high failure rate and less than 5% of patients will remain successful by 5 years.
For weight loss to occur, energy intake must be less than energy expenditure (the minimum energy required by a normal-weight adult who stays in bed is approximately 0.8 kcal/min, or 1150 kcal/day). As a guideline, a normal adult requires approximately 22-25 kcal/kg nutrient intake to maintain 1kg of body weight. A very low calorie intake (less than 800kcal/day) is not recommended.
High levels of physical activity can increase energy expenditure 4 – 8-fold. It is recommended that 60 minutes of structured physical activity be undertaken most days of the week, and for a minimum of 3 - 4 days per week to be an effective tool in weight maintenance.
A combination of resistance training as well as aerobic exercise is needed to optimize the reduction in visceral adiposity, decrease the percentage body fat and increase the percentage muscle mass.
Dietary and lifestyle interventions, combined with pharmacologic weight loss treatment provide modest weight loss, and may improve markers of cardiovascular risk factors. These benefits however occur mainly in patients with cardiovascular risks.