Obesity is a global public health issue. Although the etiology of this global epidemic is multifactorial, most sufferers would be delighted to find a relatively effortless way to lose weight. Herbal "weight loss pills" can fit the bill. The authors systematically review the scientific evidence concerning various weight loss agents that are available over the counter or in food stores. The review provides a starting point to make informed choices among nutraceutical agents promoted for weight loss, as well as advice for incorporating healthy alternatives in the diet.

In the United States, approximately 5% of the population is malnourished or has low body weight, which can adversely affect immune function. Malnutrition is more prevalent in older adults and is often a result of energy imbalance from various causes. Dietary supplementation to promote positive energy balance can reverse malnutrition, but has not been assessed for its effect on immune parameters. This 8-week clinical feeding trial evaluated the effect of a commercially available, high-protein, high-energy formula on body weight and immune parameters in 30 adult volunteers with body-mass indices (BMI) <21 kg/m2. After the intervention, participants gained a mean of 3.74 lbs and increased BMI by 0.58 kg/m2. The intervention improved lean body mass and limited body fat accumulation. However, no clinically significant improvements in immune measures were observed. These results support the use of high-protein, high-energy supplements in the treatment of underweight/malnutrition. Further investigation utilizing feeding studies of longer duration, and/or studying severely malnourished individuals may be needed to detect an effect on immune parameters of weight gain promoted by nutritional supplements.