S
September
Guest
Study links high-carbs and weight loss
http://www.ohio.com/mld/ohio/news/7801389.htm
CHICAGO - In the midst of the low-carb craze, a new study suggests that by eating lots of
carbohydrates and little fat, it is possible to lose weight without actually cutting calories - and
without exercising, either.
The study was small, consisting of just 34 overweight adults who either ate the recommended diet
for three months; ate the recommended diet and exercised regularly; or ate pretty much what they
usually eat.
All meals were prepared for participants, who were instructed to eat as much as they wanted. They
also were told to return any uneaten food, which the researchers said enabled them to calculate
calorie intake.
Many doctors dispute whether people can lose weight without reducing their food intake, and at least
one questioned the study's accuracy.
But the diet is more compatible with conventional notions of healthful eating than the fatty, low-
carbohydrate Atkins and South Beach diets.
Participants on the recommended diet lost about 7 pounds without cutting calories and without
exercise, and almost 11 pounds with 45 minutes of stationary bike-riding four times weekly. The
control group lost no weight.
The findings appear in Monday's Archives of Internal Medicine.
Gary Foster, clinical director of the University of Pennsylvania's Weight and Eating Disorders
Program, said he suspects participants who lost weight ate less than what was reported. He said that
while he recommends a low-fat, high carb diet to patients, without calorie reduction it would be "a
public health disaster."
"The whole idea that you could lose weight without reducing energy intake flies in the face of 100
years of data," Foster said.
Lead author William Evans of the University of Arkansas for Medical Sciences stood by his findings.
"Calories in minus calories out does not always determine the amount of weight loss," Evans said.
"This is because we metabolize fats and carbohydrates very differently."
American Dietetic Association spokeswoman Cindy Moore agreed and said with low-carb diets hogging
the spotlight, "it may be a reminder that we can lose weight in a variety of different ways."
Foods on the successful diets included high-fiber cereal, vegetarian chili, whole-wheat spaghetti,
many fruits and vegetables, and skim milk. Daily calories totaled about 2,400, similar to
participants' usual consumption.
The control group also received prepared meals with similar calories, but the foods included
sausage, scrambled eggs, macaroni and cheese, French fries, whole milk and fewer fruits and
vegetables.
The successful diet was not tested against Atkins and other low-carb regimens, which contain more
fat and fewer carbs than the control group diet.
Abstract from Archives of Internal Medicine:
Effects of an Ad Libitum Low-Fat, High-Carbohydrate Diet on Body Weight, Body Composition, and Fat
Distribution in Older Men and Women A Randomized Controlled Trial
Nicholas P. Hays, PhD; Raymond D. Starling, PhD; Xiaolan Liu, MD; Dennis H. Sullivan, MD; Todd A.
Trappe, PhD; James D. Fluckey, PhD; William J. Evans, PhD
Arch Intern Med. 2004;164:210-217.
Background: The efficacy of ad libitum low-fat diets in reducing body weight and fat in overweight
and obese adults remains controversial.
Methods: We examined the effect of a 12-week low-fat, high–complex carbohydrate diet alone (HI-CHO)
and in combination with aerobic exercise training (HI-CHO + EX) on body weight and composition in 34
individuals with impaired glucose tolerance (20 women and 14 men; mean ± SEM age, 66 ± 1 years).
Participants were randomly assigned to a control diet (41% fat, 14% protein, 45% carbohydrates, and
7 g of fiber per 1000 kcal), a HI-CHO diet (18% fat, 19% protein, 63% carbohydrates, and 26 g of
fiber per 1000 kcal), or a HI-CHO diet plus endurance exercise 4 d/wk, 45 min/d, at 80% peak oxygen
consumption (HI-CHO + EX). Participants were provided 150% of estimated energy needs and were
instructed to consume food ad libitum. Total food intake, body composition, resting metabolic rate,
and substrate oxidation were measured.
Results: There was no significant difference in total food intake among the 3 groups and no
change in energy intake over time. The HI-CHO + EX and HI-CHO groups lost more body weight (–4.8
± 0.9 kg [P
= .003] and –3.2 ± 1.2 kg [P = .02]) and a higher percentage of body
fat (–3.5% ± 0.7% [P = .01] and –2.2% ± 1.2% [P = .049]) than controls (–0.1 ± 0.6 kg and 0.2% ±
0.6%). In addition, thigh fat area decreased in the HI-CHO (P = .003) and HI-CHO + EX (P<.001)
groups compared with controls. High carbohydrate intake and weight loss did not result in a
decreased resting metabolic rate or reduced fat oxidation.
Conclusion: A high-carbohydrate diet consumed ad libitum, with no attempt at energy restriction or
change in energy intake, results in losses of body weight and body fat in older men and women.
http://www.ohio.com/mld/ohio/news/7801389.htm
CHICAGO - In the midst of the low-carb craze, a new study suggests that by eating lots of
carbohydrates and little fat, it is possible to lose weight without actually cutting calories - and
without exercising, either.
The study was small, consisting of just 34 overweight adults who either ate the recommended diet
for three months; ate the recommended diet and exercised regularly; or ate pretty much what they
usually eat.
All meals were prepared for participants, who were instructed to eat as much as they wanted. They
also were told to return any uneaten food, which the researchers said enabled them to calculate
calorie intake.
Many doctors dispute whether people can lose weight without reducing their food intake, and at least
one questioned the study's accuracy.
But the diet is more compatible with conventional notions of healthful eating than the fatty, low-
carbohydrate Atkins and South Beach diets.
Participants on the recommended diet lost about 7 pounds without cutting calories and without
exercise, and almost 11 pounds with 45 minutes of stationary bike-riding four times weekly. The
control group lost no weight.
The findings appear in Monday's Archives of Internal Medicine.
Gary Foster, clinical director of the University of Pennsylvania's Weight and Eating Disorders
Program, said he suspects participants who lost weight ate less than what was reported. He said that
while he recommends a low-fat, high carb diet to patients, without calorie reduction it would be "a
public health disaster."
"The whole idea that you could lose weight without reducing energy intake flies in the face of 100
years of data," Foster said.
Lead author William Evans of the University of Arkansas for Medical Sciences stood by his findings.
"Calories in minus calories out does not always determine the amount of weight loss," Evans said.
"This is because we metabolize fats and carbohydrates very differently."
American Dietetic Association spokeswoman Cindy Moore agreed and said with low-carb diets hogging
the spotlight, "it may be a reminder that we can lose weight in a variety of different ways."
Foods on the successful diets included high-fiber cereal, vegetarian chili, whole-wheat spaghetti,
many fruits and vegetables, and skim milk. Daily calories totaled about 2,400, similar to
participants' usual consumption.
The control group also received prepared meals with similar calories, but the foods included
sausage, scrambled eggs, macaroni and cheese, French fries, whole milk and fewer fruits and
vegetables.
The successful diet was not tested against Atkins and other low-carb regimens, which contain more
fat and fewer carbs than the control group diet.
Abstract from Archives of Internal Medicine:
Effects of an Ad Libitum Low-Fat, High-Carbohydrate Diet on Body Weight, Body Composition, and Fat
Distribution in Older Men and Women A Randomized Controlled Trial
Nicholas P. Hays, PhD; Raymond D. Starling, PhD; Xiaolan Liu, MD; Dennis H. Sullivan, MD; Todd A.
Trappe, PhD; James D. Fluckey, PhD; William J. Evans, PhD
Arch Intern Med. 2004;164:210-217.
Background: The efficacy of ad libitum low-fat diets in reducing body weight and fat in overweight
and obese adults remains controversial.
Methods: We examined the effect of a 12-week low-fat, high–complex carbohydrate diet alone (HI-CHO)
and in combination with aerobic exercise training (HI-CHO + EX) on body weight and composition in 34
individuals with impaired glucose tolerance (20 women and 14 men; mean ± SEM age, 66 ± 1 years).
Participants were randomly assigned to a control diet (41% fat, 14% protein, 45% carbohydrates, and
7 g of fiber per 1000 kcal), a HI-CHO diet (18% fat, 19% protein, 63% carbohydrates, and 26 g of
fiber per 1000 kcal), or a HI-CHO diet plus endurance exercise 4 d/wk, 45 min/d, at 80% peak oxygen
consumption (HI-CHO + EX). Participants were provided 150% of estimated energy needs and were
instructed to consume food ad libitum. Total food intake, body composition, resting metabolic rate,
and substrate oxidation were measured.
Results: There was no significant difference in total food intake among the 3 groups and no
change in energy intake over time. The HI-CHO + EX and HI-CHO groups lost more body weight (–4.8
± 0.9 kg [P
= .003] and –3.2 ± 1.2 kg [P = .02]) and a higher percentage of body
fat (–3.5% ± 0.7% [P = .01] and –2.2% ± 1.2% [P = .049]) than controls (–0.1 ± 0.6 kg and 0.2% ±
0.6%). In addition, thigh fat area decreased in the HI-CHO (P = .003) and HI-CHO + EX (P<.001)
groups compared with controls. High carbohydrate intake and weight loss did not result in a
decreased resting metabolic rate or reduced fat oxidation.
Conclusion: A high-carbohydrate diet consumed ad libitum, with no attempt at energy restriction or
change in energy intake, results in losses of body weight and body fat in older men and women.