This Caught My Attention...
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This Caught My Attention...
| Sun, 09-13-2009 - 8:16am |
I was reading about this recently and thought it interesting.
What do you think about this?
Cardiologist's Confession: Why I Quit Low-Carbohydrate Diets
Low-carb diets can lead to weight loss, but are they healthy for the heart? Cardiologist Anthony Rosenzweig, MD, Director of Cardiovascular Research in Beth Israel Deaconess Medical Center and Professor of Medicine at Harvard Medical School, was so convinced that they were heart-healthy that he used them himself to lose weight. But then his lab did some research that convinced him to find a healthier way. Here's his story: A few years ago, like many middle-aged Americans, I was experimenting with a low-carbohydrate diet. As a cardiologist, I knew that the few randomized controlled trials of this diet suggested that are effective ways to lose weight and, somewhat surprisingly - given how high in fat and cholesterol they sometimes are - had relatively little adverse effect on the usual markers of cardiovascular risk, such as serum cholesterol or CRP .
Dr. Shi Yin Foo, a talented physician-scientist and cardiologist working in my laboratory, was taken aback by what I was eating at lunch. She'd ask how I could eat that way and would tell me about the last low-carb patient she'd admitted to the hospital with a heart attack. I'd point out that there were no controls for her observations, and that - as with the clinical studies - my own cholesterol and other markers remained unchanged.
Of course, what we really wanted to know was what was happening to the blood vessels, and the risk of future heart attack or stroke on these diets. These questions are very difficult to address in clinical trials, and thus remains unanswered. Finally, I asked Shi Yin to do the mouse experiment - so that we could know what happens in the blood vessels and so I could eat in peace.
Mice were put on one of three diets: a standard diet of mouse "chow" (65 percent carbohydrate; 15 percent fat; 20 percent protein); a "Western diet" in keeping with the average human diet (43 percent carbohydrate; 42 percent fat; 15 percent protein; and 0.15 percent cholesterol); or a custom-made low-carb/high-protein diet (12 percent carbohydrate; 43 percent fat; 45 percent protein; and 0.15 percent cholesterol). In order to keep the calorie count the same in all three diets, we had to substitute a nutrient to replace the carbohydrates. We decided to substitute protein because that it what people typically do when they are on these diets. Similar to the clinical studies, mice fed the low-carb/high-protein diet gained 28 percent less weight than the mice fed the Western diet, and had similar serum cholesterol levels and other markers of vascular risk.
However, their blood vessels showed significantly more atherosclerotic plaque, the kinds of blockages that lead to heart attack and stroke. In a second series of experiments, we found that mice on the low-carbohydrate, high-protein diet were significantly less able to grow new blood vessels in regions deprived of blood flow.
These results point out that there can be a disconnect between weight loss or serum markers and vascular health, and that vascular health can be affected by macronutrients other than fat and cholesterol - in this case, protein and carbohydrates. Although the precise mechanisms are still being worked out - and caution is always warranted in extrapolating from effects in mice to a clinical situation - the results succeeded in getting me off a low-carb diet. Most likely there are no quick fixes and a moderate and balanced diet, coupled with regular exercise, is probably best for most people.
However, their blood vessels showed significantly more atherosclerotic plaque, the kinds of blockages that lead to heart attack and stroke. In a second series of experiments, we found that mice on the low-carbohydrate, high-protein diet were significantly less able to grow new blood vessels in regions deprived of blood flow.
These results point out that there can be a disconnect between weight loss or serum markers and vascular health, and that vascular health can be affected by macronutrients other than fat and cholesterol - in this case, protein and carbohydrates. Although the precise mechanisms are still being worked out - and caution is always warranted in extrapolating from effects in mice to a clinical situation - the results succeeded in getting me off a low-carb diet. Most likely there are no quick fixes and a moderate and balanced diet, coupled with regular exercise, is probably best for most people.

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I did the low carb high protein diet
Ok...only for a few months. Hmmm...my neighbors are still on it, but I am not saying nothing. They seem happy to be on it.
At least you know about it and now I know.
I am so glad to have started with the portioning instead of "the other one". I learned so much from here and still learning of things. I do not want to leave here.
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