When an obese individual loses weight, there is a good chance that maintaining weight loss will be a lifelong battle. Nonetheless, certain behaviors can influence weight maintenance success. For instance, drinking diet soda has been shown to be more effective than drinking water at not only promoting weight loss, but at keeping the weight off over one year. By contrast, the speed at which one loses weight does not appear to influence weight loss maintenance.
Another possible tool for dieters is mindfulness-based approaches to increase awareness in the moment and promote adaptive self-regulation. There is support for its use in improving maladaptive eating behaviors, such as binge eating and emotional eating, that can no doubt impede weight loss or cause weight gain. However, whether mindfulness can aid weight loss and weight loss maintenance was only recently investigated by Daubenmier et al from the University of California, San Francisco.
This randomized controlled trial involved two comparative arms that ran parallel for an initial 5.5-month diet-exercise intervention with or without mindfulness components and a subsequent 1-year follow-up. Outcome measurements were made at baseline and 3, 6, 12, and 18-months after beginning the study.
Both interventions included 16 sessions lasting 2 to 2.5 hours over the 5.5-month period in which identical diet-exercise guidelines were presented in 45-minute segments per session. The diet component included the typical recommendations to reduce caloric intake through substituting whole grains for simple carbohydrates and increasing consumption of fresh fruits and vegetables, healthy oils, and proteins. The exercise component included recommendations to increase daily activity and moderate intensity exercise, primarily through walking, and discussed the importance of strength training.
The difference between the 2 intervention groups came from what was done during the remaining 1.5 hours of each session. The mindfulness-enhanced program added mindfulness training for stress management, eating, and exercise. This included sitting meditation, yoga postures, and mindful walking, all of which was recommended to be performed for 30 minutes each day, six days per week, as well as becoming more aware of physical sensations of hunger, stomach fullness, taste satisfaction, food cravings, and the identification of emotional and other eating triggers. By contrast, the control group received further additional diet-exercise content and cognitive-behavioral stress management techniques.
… doesn’t help
The study began with 194 middle-aged men and women (82%) with obesity who were recruited from the local area. Adherence was similar between groups at all time points, being 81% in the mindfulness group after 18-months and 71% in the control group. Despite being asked to meditate for 3 hours/week, the group averaged 2.1 hours/week. They also reported eating mindfully for 12 meals per week. Thus, adherence to recommendations was good, but it certainly wasn’t great.
At no time was there a statistical difference between the mindfulness group and the control group in terms of weight loss. However, the results did still favor the mindfulness group, which lost 4.5 kg after six months and 4.2 kg after 18 months. The control group lost 3.3 and 1.7 kg, respectively.
Similar observations were made for blood-borne measurements, with the only statistically significant differences between groups being a 4 mg/dL reduction in fasting glucose at 18-months, a 15 mg/dL reduction in triglycerides at 6-months, and a 0.6 reduction in the triglyceride to HDL ratio at 12-months in the mindfulness group compared to the control group. Blood pressure, C-reactive protein, other blood lipids, HbA1c, and HOMA-IR were not significantly different between groups.
Be mindful of study limitations
This was a largely thoughtful and well-conducted weight loss trial with a large sample size, an active control group, and assessment of a variety of cardiometabolic markers. Although no differences in weight loss were observed, the study does make a useful contribution to the literature.
Most long-term weight loss interventions show maximal weight loss around 6-months, with a steady regain thereafter. It is therefore notable in the current study that the mindfulness group regained an average of only 0.3 kg from 6 to 18 months, compared to a 1 kg regain in the control group.
However, any differences in weight loss did not appear to have a clinically meaningful impact on other risk factors, as most were not significantly different between groups, even at 6-months when the difference in weight was greatest. Of those that did become significant later on (at 12- and 18-months), there is a possibility this was a chance finding, as corrections for the multiple comparisons being made were not performed. Nonetheless, 10 of the 11 assessed risk factors favored the mindfulness group at 12-months and 9 of 11 at 18-months.
Interestingly, the authors suggest that lower ratings for one of the mindfulness instructors may have reduced the impact of the mindfulness intervention. Based on feedback from the participants, instructor C was rated as less helpful than instructors A and B. In a post-hoc analysis, the researchers did indeed show that weight loss at 18-months (but not 3-, 6-, or 12-months) with instructors A & B (-6.3 kg) was significantly greater than with instructor C (-2.0 kg) and when compared to the control group. Clearly the type of mindfulness instruction plays a role in its success, although future research will be needed to figure out the nitty-gritty of its impact.
Overall it appears that mindfulness has potential to be a beneficial adjunct to standard dietary and exercise counseling, although more research is needed to find out how the type of mindfulness, duration of training, duration of practice by the participants, and baseline stress or emotional status affect its impact.