Losing weight: Does it take a village?

This study in The New England Journal of Medicine compared the effectiveness of 4 diets for weight loss and weight maintenance.

The results are interesting. The accompany editorial is even better.

First, the details.

• 811 overweight adults were randomly assigned a diet.
  • Comparisons were made between low vs high fat, average vs high protein, and highest vs lowest carbohydrate content.
• The energy from fat, protein, and carbohydrates varied but met guidelines for cardiovascular health.
• Participants were offered group and individual instructional sessions for 2 years.

And, the results.

• At 6 months, participants assigned to each diet lost an average of 6 kg (13 lb), which represented 7% of their initial weight.
• They began to regain weight after 12 months.
• 80% of participants completed the study, with an average weight loss of 4 kg (9 lb).
• 14% to 15% of the participants had a reduction of at least 10% of their initial body weight.
• Satiety, hunger, satisfaction with the diet, and attendance at group sessions were similar for all diets.
  • Attendance was associated with weight loss (0.2 kg [1/2 lb] per session attended).
• The diets improved cholesterol-related risk factors and fasting insulin blood levels.

The bottom line?
Dieting was associated with weight loss, but the type of diet had no significant effect. And the participants didn’t achieve the weight loss anticipated.

Prof. Martijn Katan at Vrije Universiteit in Amsterdam, The Netherlands observes in his editorial, “It is obvious by now that weight losses among participants in diet trials will at best average 3 to 4 kg after 2 to 4 years… less among people who are poor or uneducated — groups that are hit hardest by obesity.”

“We do not need another diet trial;” asserts Prof. Katan, “we need a change of paradigm.”

He refers us to a community-based effort to prevent overweight in schoolchildren living in 2 small towns in France in 2000. Everyone joined in an effort to encourage children to eat better and move around more. The towns built sporting facilities and playgrounds, mapped out walking itineraries, and hired sports instructors. Families were offered cooking workshops, and families at risk were offered individual counseling.

By 2005 the prevalence of overweight in children had fallen to 9%, whereas it increased to 18% in the neighboring neighboring towns — in line with the national trend.

“Like cholera,” concludes Prof. Katan, “obesity may be a problem that cannot be solved by individual persons but that requires community action.

2/26/09 15:06 JR