Medical nutrition therapy (MNT) provided by a Registered Dietitian results in both statistically and clinically significant weight loss in otherwise healthy overweight and obese adults. Four studies regarding the effectiveness of medical nutrition therapy for under six months reported significant weight losses of approximately one to two pounds per week. Four studies regarding the effectiveness of MNT from six to twelve months reported significant mean weight losses of up to 10% of body weight. Four studies report maintenance of this weight loss beyond one year. In these studies, both individual and group sessions were employed with weekly and monthly sessions. 

• Grade I means there is Good/Strong evidence supporting the statement;
• Grade II is Fair;
• Grade III is Limited/Weak;
• Grade IV is Expert Opinion Only;
• Grade V is Not Assignable.
• High (A) means we are very confident that the true effect lies close to that of the estimate of the effect;
• Moderate (B) means we are moderately confident in the effect estimate;
• Low (C) means our confidence in the effect estimate is limited;
• Very Low (D) means we have very little confidence in the effect estimate.
• Ungraded means a grade is not assignable.