Obesity is a significant and increasing health problem worldwide. It is defined as a body mass index (BMI) of >30kg/m2 or >25kg/m2 with obesity-related comorbidity. Obesity is associated with increased morbidity and mortality, primarily through increased risk of cardiovascular disease, hypertension, and diabetes mellitus (DM).
Weight loss, and more importantly the maintenance of weight loss, can promote health benefits. These include lower cholesterol and blood sugar levels, lower blood pressure, less stress on bones and joints, and less work for the heart. It is vital to maintain weight loss to obtain health benefits over a lifetime. While some improvement in cardiovascular risk has been demonstrated with a weight loss of 2 to 3%, clinical guidelines recommend a weight loss of 5% to 10% over 6 months to produce significant improvements in cardiovascular risk factors.
However, maintenance of weight loss has traditionally been extremely difficult for patients with obesity. Weight loss maintenance is crucial for obesity management. The percentage of individuals who lose weight and successfully maintain the loss has been estimated to be small and in long term interventions it has been shown that up to 90% of weight-reduced individuals return to their previous body weight. In 1959, Stunkard and McLaren-Hume showed that only 2% of 100 patients with obesity maintained significant weight loss at 2 years. More recently, in 2005, Wing and Phelan showed that 80% of 4000 patients in the National Weight Control Registry failed to maintain weight loss after 1 year. Weight cycling is losing and regaining weight multiple times. Some studies suggest that weight cycling, also called "yo-yo dieting," may result in some health risks. These include high blood pressure, gallbladder disease, and high cholesterol. However, these studies are not true for everybody. The best strategy is to avoid weight cycling and to maintain healthy weight.
The Key protective factors for weight loss maintenance include adherence to Physical activity and exercise training, Healthy diet, and self-monitoring of weight that result in reduced energy intake and to enhance energy expenditure. Healthy diet and being active are essential component of a weight loss program. Continuing to use behavioral strategies is necessary to maintaining weight. Conversely, poor adherence to Physical activity and dietary programs was associated with failure to maintain weight loss. Although exercise contributes to multiple health benefits, and most of the research suggests that it can play a role in both short- and long-term weight loss and weight maintenance, often have a difficult time engaging in a regular exercise program and continuing that program as a lifestyle modification. The effectiveness of Physical activity in the maintenance of weight loss is limited by patient adherence, thus becoming a complex issue comprising physical, physiological, and behavioral aspects. This is compounded by both the physiological response from the body to calorie restriction and the physical and mental effort required to maintain sustained Physical activity and diet programs. Therefore, a consistent, combined, multidisciplinary approach is required to give patients the optimum support to maintain weight loss.
In a study showed successful weight-loss maintainers rely on physical activity to remain in energy balance to avoid weight regain. Successful weight-loss maintainers are individuals who maintain a reduced body weight of 30 pounds or more for over a year.
In 2001, the American College of Sports Medicine recommended at least 150 minutes of Physical activity per week to promote and maintain weight loss. However, they advised that 200 to 300 minutes of Physical activity per week would be more effective in maintaining weight loss. This would correlate to 60 minutes of walking per day. However, in 2009, this position was revised to recommend 150 minutes as a minimum level of Physical activity per week, with >250 minutes per week of Physical activity optimal for weight loss maintenance.
Karimi, H
Master of clinical Nutrition & Dietetics
References
1-Physical Activity and Weight Loss Maintenance. National Center for Biotechnology Information.2021.
