Low-Carb Diets The Right Way to Go

For immediate release: April 20, 2007


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Are your jeans too tight after eating too many cookies or taking seconds of a rich dinner entree? Or, are you a lifetime member of the "Need to Lose Weight Club?" Either way, if you want to slim down, you likely will turn to a "diet book" for weight loss advice.

That's when the confusion can set in. Which plan will you choose? Atkins, South Beach, Dr. Phil or the classic Weight Watchers? Which one will do the best job in helping you quickly and painlessly take off the pounds and inches?

The low-carbohydrate (carb) craze has taken over our collective approach to dieting. We can now buy low-carb everything: pasta, bread, cereal, peanut butter and even beer. But is low carb the best way to go? Or, is a traditional low-fat diet better? Unfortunately, the verdict is not in. Keep reading to learn about the science, or lack thereof, behind the low-carb plans.

How the Low-Carb Diets Work

Low-carb diets are based on the following premise:

Carbohydrates, particularly the "bad carbs" such as white potatoes, rice, pasta and bread, cause a quick rise in blood sugar. High blood sugar levels result in increased insulin levels, and increased insulin levels lead to weight gain because of increased hunger.

Low-Carb Terms

Glycemic Index (GI): Ranks foods according to how fast their sugars are released into the bloodstream (High GI-70 or more; Low GI-55 or less)

Glycemic Load (GL): Accounts for both the GI and how much carbohydrate a food provides in a single serving. Low-carb diets promote foods with a low GI and a low GL.

Note: Most fruits, vegetables, beans and whole grains have a low GL (low teens). However, the GI and GL increase significantly once fruit is pulverized into juice, or when whole grains are refined. Whole foods are better! For example, All-Bran has a GL of 4 and Cornflakes has a GL of 21.

By far, the two most popular low-carb diet plans are Atkins and South Beach. How do these plans compare? Check out the chart below for the specifics.


Induction (2 weeks):
Ongoing Weight Loss (OWL)
Phase 1 (2 weeks)
Phase 2 (during remainder of weight loss)

Phase 3 (maintenance)
Carb Allowance
(Minimum need:
100-150 grams/day)

Not more than 20 grams/day (= 1 1/2 slices bread)
OWL: up to 60 grams/day

Phase 1: Sample meal plan has close to 20 grams
Phase 2: Sample meal plans have 65-90 grams

Promotes High Protein Yes No
Fat Allowed

Until recently, no limit on type or amount Now: No more than 20% of calories as saturated fat (NIH: less than 7% saturated fat) Heart-healthy fats (vegetable oils, canola, olive, etc). Fatty fish & nuts
Heart-healthy proteins
Most Negative Features

Not heart healthy (excess saturated fat & cholesterol)
Potential for excessive red meat intake
Increased risk for colon cancer
Potential for increased bone loss/or kidney damage (due to high protein) if followed long-term (more than 1 year)
Limits some healthy foods because of Glycemic Index (e.g. bananas, carrots)
Does not account for Glycemic Load

What The Research Says

  • Last year, three research teams reported the results of their controlled studies comparing low-carb to traditional low-fat diets. The results show that over a six-month period, obese people lost more weight on a low-carb plan. The reason for the extra weight loss is unclear.
  • It's important to note, however, that we don't know the long-term health effects of low-carb diets. As with many health interventions, more research is needed.

What's the Bottom Line?

If you choose to follow a low-carb diet plan, be sure to choose one that:

  • Includes heart-healthy fats and protein foods.
  • Does not severely limit carbohydrate, but includes low GI/GL carbs like beans, whole fruit, vegetables and whole grains.
  • Overall, the South Beach plan passes the nutrition muster better than Atkins!
  • Beware: Low carb does not always equal low calorie or heart healthy. For example,
    the "Atkins-friendly" foods on the TGI Friday's® menu include a New York strip with bleu cheese and Buffalo wings. Remember that a calorie is a calorie is a calorie. You must eat less than your body's needs to lose weight. There is nothing magical about eating low carb.
  • Include exercise in your weight loss plan. Exercise builds muscle mass, which helps your body burn calories more efficiently.
  • MOVE MORE and EAT LESS! Some advice never changes!