Mobile phone text messaging helps overweight and obese adults lose weight

Liu F, Kong X, Cao J, et al. Mobile phone intervention and weight loss among overweight and obese adults: A meta-analysis of randomized controlled trials Am J Epidemiol. 2015;181:337-348.

Review question

Does mobile phone text messaging promote weight loss for overweight and obese adults?

Background

Obesity increases the risk of death and disease, and leads to increased health-care costs worldwide. Lifestyle changes can help people lose weight, but many find it challenging to maintain the weight loss long-term. Mobile phone text messages – in the form of short message service (SMS) and multimedia message service (MMS) – are increasingly being used to send reminders and encouragement about healthy behavior and weight loss. However, there is conflicting research about the effectiveness of using these types of messages for weight loss.

How the review was done

This is a meta-analysis of 14 randomized controlled trials that included 1337 participants. All studies were published between 2004 and 2013.

Key features of the studies were:

• All participants were adults (over 18 years of age)
• All participants were overweight, and had a body mass index (BMI) over 25
• The studies differed by duration (1 month to 12 months), size (30 to 250 participants), location (most were conducted in North America and Europe), and how often participants received messages.
• The mobile phone messages delivered information about healthy eating, physical activity and weight loss via SMS alone vs. SMS combined with MMS.
• Researchers measured changes in body weight, BMI, waist circumference, waist-to-hip ratio and body fat percentage among study participants.
• Results were compared to people in control groups who did not receive the mobile phone messages, but otherwise received the same information and support as study participants (eg. the usual care, monitoring of physical activity, paper education materials, group sessions and pedometer).

What the researchers found

People who received the mobile phone messages lost significantly more weight (average loss of 1.44 kg) and improved BMI (average change of -0.24 units) than people in control groups. There was no significant difference in waist circumference between the two groups. The type of mobile phone approach (SMS alone vs. SMS combined with MMS) and length of the studies (less or greater than six months) did not make a significant difference. This means that these types of approaches have the potential to help people sustain weight loss for over six months. No studies measured impacts on waist-to-hip ratio and only one study measured impacts on body fat.

Conclusion

Mobile phone messages can be used to promote weight loss in overweight and obese adults. More research is needed about the longer-term effectiveness of these types of approaches (over one year).