Research
Adherence
Nutrisystem produces greater short-term weight loss (3 months) compared to control or counseling, but long-term efficacy (12 months) is unproven due to lack of long-term trials.
Nutrisystem can help you lose weight in the short term (3 months) if you are willing to use their meal replacements and attend sessions. However, there is no evidence that it works better than other methods after 12 months. If your goal is long-term weight loss, you need to find a way to maintain the habits learned during the program.
ModerateQualifiesMEDIUM confidence
Nutrisystem resulted in at least 3.8% greater weight loss at 3 months than control/education and counseling. ... Nutrisystem shows promising weight-loss results; however, additional studies evaluating long-term outcomes are needed.
Why this rating
Moderate to High ROB, but limited duration of studies.
Source
Efficacy of Commercial Weight-Loss Programs
Kimberly A. Gudzune et al. · Annals of Internal Medicine · 2015
DOI 10.7326/m14-2238
systematic_reviewCited 331×
Read the paper DOI resolved against Crossref · corpus check 2026-06-10
More from this paper
- Commercial weight-loss programs Weight Watchers and Jenny Craig produce statistically significant and clinically relevant greater weight loss compared to control or behavioral counseling interventions at 12 months.Moderate
- Very-low-calorie (VLC) meal replacement programs (HMR, Medifast, OPTIFAST) produce greater short-term weight loss than counseling, but effects attenuate after 6 months and carry risks of gallstones.Moderate
- Atkins diet produces greater short-term weight loss than control or counseling, but long-term (12 months) efficacy is modest (0.1-2.9% greater) and similar to other diets.Moderate
Related findings · Adherence
- Regular physical activity (at least 150 minutes/week of moderate-intensity) reduces all-cause and cardiovascular mortality by 20-30% and lowers the risk of type 2 diabetes by 25-35%.Strong
- Increasing physical activity from a sedentary lifestyle to an active one in middle adulthood significantly reduces the risk of coronary events compared to remaining sedentary.Strong
- Resistance exercise is the only intervention capable of consistently restoring muscle function and strength in sarcopenia, partially overcoming age-related anabolic resistance.Strong
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