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Low-Carb Diets: The Right Way to Go?

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.

  ATKINS SOUTH BEACH
Phases



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

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

Induction
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

What's the Bottom Line?

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


This page was last updated on: April 20, 2007.

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