For a more detailed explanation of the study, see this weeks Feature:
Low Carb Diets Vindicated
"Concerns about adverse metabolic effects of the Atkins diet were not
substantiated within the 12-month study period with over 300 overweight women.
Overweight and obesity are well-documented problems in the United States. National
dietary weight loss guidelines (a diet low in calories and fat, high in carbohydrates)
have been challenged, particularly by supporters of low-carbohydrate diets.
However, limited evidence has been available to effectively evaluate other
diets, according to background information in the article.
Christopher D. Gardner, Ph.D., of Stanford University Medical School, Stanford,
Calif., and colleagues examined the effects of four diets-3 popular and substantially
different diets and 1 diet based on national guidelines-representing a spectrum
of carbohydrate intake, on weight loss and related metabolic variables in overweight
and obese premenopausal women. The diets were Atkins (very low in carbohydrate),
Zone (low in carbohydrate), LEARN (Lifestyle, Exercise, Attitudes, Relationships,
and Nutrition; low in fat, high in carbohydrate, based on national guidelines),
and Ornish (high in carbohydrate). The study, which included 311 overweight/obese
(body mass index, 27-40) nondiabetic, premenopausal women, was conducted from
February 2003 to October 2005. Participants were randomly assigned to follow
for 12 months the Atkins (n = 77), Zone (n = 79), LEARN (n = 79), or Ornish
(n = 76) diets and received weekly instruction for 2 months, then an additional
10-month follow-up.
Besides weight loss, the participants were also measured for lipid profile
(low-density lipoprotein, high-density lipoprotein, and non-high-density lipoprotein
cholesterol, and triglyceride levels), percentage of body fat, waist-hip ratio,
fasting insulin and glucose levels, and blood pressure. Outcomes were assessed
at months 0, 2, 6, and 12.
The researchers found that weight loss was greater for women in the Atkins
diet group compared with the other diet groups at one year. Average 12-month
weight loss was 10.4 lbs for Atkins, 3.5 lbs. for Zone, 5.7 lbs. for LEARN,
and 4.8 lbs. for Ornish. At 12 months, measurements for lipids and levels of
insulin, glucose and blood pressure for the Atkins group were comparable with
or more favorable than the other diet groups.
"Concerns about adverse metabolic effects of the Atkins diet were not
substantiated within the 12-month study period. It could not be determined
whether the benefits were attributable specifically to the low carbohydrate
intake vs. other aspects of the diet (e.g., high protein intake). While questions
remain about long-term effects and mechanisms, these findings have important
implications for clinical practice and health care policy. Physicians whose
patients initiate a low-carbohydrate diet can be reassured that weight loss
is likely to be at least as large as for any other dietary pattern and that
the lipid effects are unlikely to be of immediate concern. As with any diet,
physicians should caution patients that long-term success requires permanent
alterations in energy intake and energy expenditure, regardless of macronutrient
content," the authors conclude.
JAMA. 2007;297:969-977.
====================================================
Advertisement:
Breaking News from the American Diabetes Association 66th Scientific Sessions
Did you miss the ADA Scientific Sessions in Washington, DC? Get up to
speed on the latest research and updates to current knowledge on diabetes and
dyslipidemia-FREE CME Activities from the ADA Scientific Sessions are now available! Click
here to access the interactive CME newsletter summary of several presentations
relevant to clinical practice and the CME case-based slide and audio presentations
on the real-world management of patients with diabetes and dyslipidemia recorded
at the ADA meeting. Don't miss this opportunity to learn the latest
clinical updates from one of the year's most critical diabetes events!
http://www.cemedicus.com/diabetes
|
Entries (RSS News)
