Tuesday, June 14, 2005

Low GI - Lower Cardiovascular Disease Risk

Reuters ran an article last week, Low-Glycemic May be Better than Low-Fat, highlighting the findings of a study published in the American Journal of Clinical Nutrition, May 2005 titled, "Effects of an ad libitum low-glycemic load diet on cardiovascular disease risk factors in obese young adults."

The media, it seems, is always searching for the "next big thing" and these days it's anything that isn't "low-carb" - or at least isn't named low-carb! Funny thing - low-glycemic diets are controlled-carb and very often even low-carb. But let's not call it that, OK?

Back to the study data...

This was a nicely done study - controlled and randomized and even ad libidum (eat whatever and however much you want) for the low-glycemic participants. Researchers randomized participants into two groups:
  • Low-Glycemic Group (LG) - allowed to eat anything they wanted from the low-glycemic foods list (energy intake averaged 40-45% of calories but was not specifically restricted from the start) along with 30-35% of energy from fat with the remaining calories fulfilled with protein, 20-30%.
  • Low-Fat Group (LF) - calorie restricted to maintain a calorie deficit (200-500 calorie per day deficit), with no more than 30% of calories from fat, 55-60% of calories from carbohydrate and the remaining calorie requirements fulfilled with protein, 10-15%.

Do I need to tell you who did better?

The findings included:

  • At 6-months the LG group lost 8.4% of their body weight; the LF group lost 7.8%
  • At one-year, the LG group had maintained a loss of 7.8% of body weight; the LF group 6.1%
  • The LG group showed significantly greater (P=0.005) mean decline in plasma triacylglycerols than did the conventional diet group (LG -37.2%; LF -19.1%)
  • Mean plasminogen activator inhibitor 1 concentrations decreased (–39.0%) in the LG group but increased (33.1%) in the LF group (P = 0.004).
  • Changes in cholesterol concentrations, blood pressure, and insulin sensitivity did not differ significantly between the groups.

So what does this mean?

The researchers concluded that the low-glycemic approach, in an ad libidum setting, "may be more efficacious than a conventional, energy-restricted, low-fat diet in reducing cardiovascular disease risk. "

As more evidence continues to mount, it is going to be harder and harder to ignore the efficacy of controlled-carb nutrition, which includes low-carb diets as an effective weight-loss tool.

1 comment:

  1. Regina, Your courage is matched only by your knowledge. Many thanks for saying in print things that others seem to be too frightened or too ignorant to say.
    Old but still learning.