A 2005 Washington Post article titled "Low-Carb Fad Fades, And Atkins Is Big Loser" reported the end of the low carb fad.
In 2007, low carb guru Gary Taubes published Good Calories, Bad Calories (UK edition: The Diet Delusion) detailing the history of the science behind the low carb hypothesis. In 2008 June, the hardcover edition reached an Amazon.com sales rank of 1,636.
The fad may or may not be over, but what is the science behind low carbohydrate dieting?
Low Carb Research Papers
Research papers published in reputable journals should be the main source of information. Claims by experts (both pro and anti-low carb), no matter how logical-sounding, should be ignored unless substantiated by scientific research. Claims such as:
- A calorie is a calorie; what matters is how much is eaten, and how much is burned through exercise
- Low carb diets are dangerous because they are not balanced
- Exercise helps with weight loss
Searching the Internet for "low carb" and "abstract" will throw up serious scientific papers on low carb research (standard format for research papers is to have an abstract section to summarize the findings).
Do Low Carb Diets Work?
Maybe.
A study by Frederick F. Samaha M.D. and others (reported in the May 22nd 2003 edition of the New England Journal of Medicine) found that severely obese people on a low carb diet (compared to those on a low fat diet)
- Lost more weight
- Had greater decreases in triglyceride levels (healthier)
- Had greater improvements in insulin sensitivity (healthier, measured only for non diabetic subjects)
However they recommend caution in interpreting the results due to
- The small number of people involved (of the 132 people recruited, 79 people completed the trial)
- The short duration of the trial (six months)
- The relatively small differences encountered
They also caution that the effects of long term low carbo diets needs to be studied.
A survey by Dena M. Bravata, MD, MS and others (Journal of the American Medical Association April 9th 2003) of low carb research between 1966 and 2003 found the evidence to be neutral. They do caution against low carb diets
- For people older than 50
- Lasting more than 90 days
- With less than 20 grams of carbs a day
Are Low Carb Diets Harmful?
No, at least not in the short term.
A study by Thomas L. Halton, Sc.D. and others (New England Journal of Medicine, November 9th 2006), showed no increase in heart disease in women who ate more protein and fat and less carbohydrate. They analyzed twenty years of data in the Nurses' Health Study, covering 82,802 women.
Another study by William S. Yancy, Jr., MD, MHS and others (Annals of Internal Medicine, 18 May 2004) compared low fat and low carb diets. Over six months and with 120 volunteers, they found greater health improvements with the low carb diet:
- More weight loss
- More people sticking with the diet
- Larger triglyceride level declines (healthier)
- Larger HDL cholesterol increases (healthier)
Summary
Low carb diets probably do work, at least for some people. They are also healthy in the short term.
The main uncertainty now is whether or not there are any long term health risks.
It should be noted that scientific research is often contradictory. It is possible to find research papers that have negative findings on low carb diets.
Resources
Google search for low carb scientific research papers
What if It's All Been a Big Fat Lie? The controversial New York Times Magazine article by Gary Taubes.
