Low Calorie and Low Carb Diets
In a new weight loss study, doctors analyzed over 100 diet
studies and conclude that the key to losing weight is to limit the
amount - not the type - of food you eat.
Low Carb Diets are Low Calorie Diets
A huge meta-analysis of the wildly popular low carb diets
has proved, yet again, that there's no easy answer to weight loss.
Such low carb diets often promote the idea that weight can be
reduced by avoiding bread, pasta, and other carbohydrates while
eating as much fat and protein as one wants. But in a new weight
loss study, a team of doctors from Stanford and Yale Universities
have found that any weight loss achieved on a low carb diet comes
from consuming fewer calories, the crucial factor in a standard
weight loss diet plan. Low carb had nothing to do with
it, they say.
Low Carb Diet Industry
Low carb diets have spawned a huge industry of books, diet aids,
and prepared meals in recent years. Diets such as Sugar Busters,
The Zone, and most famously, the one espoused by Dr. Robert Atkins
in his perennial best-seller, Dr. Atkins' Diet Revolution, have
become all the rage despite skepticism expressed by much of the
medical Establishment. Atkins has argued for more than 20 years
that the bodies of most overeaters produce too much insulin, which
converts excess carbs to fat.
By switching to a low carb diet,
insulin production is decreased, food craving dampened, and stored
fat burned off, Atkins has claimed. Adherents can eat steak, eggs,
cheese, and butter but virtually no bread, pasta, fruit, or sugar
- even many vegetables are banned in a low carb diet. Numerous medical associations,
however, have warned that over time low carb diets can can be high
in fat and lead to
kidney, liver, and heart problems.
New Weight Loss Low Carb Diet Study
The new low carb diet report published in the Apr. 9 issue of the Journal of the
American Medical Assn. is the first of its kind, a review of all
the scientific literature published on low carb diets from
1996 to 2003. The researchers analyzed a total of 107 diet studies
involving 3,268 people from around the world.
Calorie Intake is Major Predictor of Weight Loss
Although the studies differed in their carb and calorie
intake, among other variables, the team was able to draw one
overriding conclusion: "The greatest predictors of weight loss
appear to be calorie intake and diet plan duration," says Dr. Dena Bravata of Stanford's Center for Primary Care & Outcomes Research.
People on diet plans of 60 or fewer grams of carbs a day (a
threshold used by many low carb diets) did lose weight, but the
loss was invariably associated with eating less and dieting
longer, rather than low carb diet intake. "The findings suggest
that if you want to lose weight, you should eat fewer calories and
do so over a long time period," says Bravata.
Neutral on Low Carb Diets
Interestingly, the researchers didn't recommend for or against
low carb diets, concluding that not enough evidence is available
to make such a determination. Most of the studies in their
analysis didn't last longer than 90 days, and none had
participants with a mean age over 53 years old. Bravata says more
studies are needed on the role of exercise in weight loss, the
long-term effects of low carb diets, and their safety for people
over age 53.
Source: Businessweek.com April 2003 |
