The purpose of this study is to look at the effects of a carbohydrate restricted, high protein, high fat diet on weight loss and health outcomes in women participating in the Curves Fitness and Weight Loss Program.

The purpose of this study is to determine if a carbohydrate restricted, high protein, high fat diet (20% carbohydrate, 45% protein, 35% fat; CC-II) promotes more favorable changes in weight loss and health outcomes compared to a traditional high carbohydrate, low protein, low fat diet (55% carbohydrate, 15% protein, 30% fat; AHA) and the Curves moderate carbohydrate restricted, high protein, and low fat diet (30% carbohydrate, 45% protein, 25% fat; CC-I).

Inclusion Criteria:

• The participant is an apparently healthy female
• The participant is between the ages of 18 and 60

Exclusion Criteria:

• The participant is pregnant or nursing, or plans to become pregnant during the next 12 months or has been pregnant in the past 12 months
• The participant has uncontrolled metabolic disorder including known electrolyte abnormalities; heart disease, arrhythmias, diabetes, thyroid disease, or hypogonadism; a history of hypertension, hepatorenal, musculoskeletal, autoimmune, or neurological disease
• The participant is currently taking thyroid, hyperlipidemic, hypoglycemic, anti-hypertensive, or androgenic medications
• The participant has taken ergogenic levels of nutritional supplements that may affect muscle mass (e.g., creatine, HMB), anabolic/catabolic hormone levels (androstenedione, DHEA, etc.) or weight loss (e.g., ephedra, thermogenics, etc.) within the past three months
• The participant is willing to participate in a regular moderate exercise program

The eligibility criteria were at the request of the study sponsor.