The comparison in this case was between a low-carb diet similar to the Atkins plan, and a low-fat, low-calorie diet which included the use of Orlistat, the prescription dose of the over-the-counter weight-loss medication Alli. The groups were followed for almost a year. Another difference between this and some other studies was that they did not exclude people with health problems such as diabetes, in fact, a third of the participants were diabetic, with many taking medicine to lower blood sugar and blood pressure.
One most measures, the outcomes were similar. Both groups lost on average a little less than 10% of body weight, and had similar improvements in risk markers such as cholesterol. The one main difference was that not only were more people in the low-carb able to reduce their blood pressure medication (of those taking medication, 47% of the low-carb group reduced or eliminated medication, compared to 21% in the Orlistat/low-fat group), but even with the reduced medication, the low-carb group as a whole had reduced blood pressure compared to the Orlistat/low-fat group. This is especially surprising because Orlistat has a slight lowering effect on blood pressure, and because both groups achieved similar weight loss. In addition to lowering blood pressure medication, more diabetics in the low-carb group were able to lower diabetes medication (81% for low-carb and 68% for Orlistat/low-fat).
Another interesting result I noticed in the study was that even though the low-carb group was not told to limit calories, their calorie reduction was about the same as the group specifically told to reduce calories. One thing low-carbers love is that they don't need to struggle to reduce food intake - it comes naturally! Also interesting was although the low-carb group was eating a greater precentage of fat than before the diet, the amount of fat stayed about the same. The low-fat/Orlistat group had a large fat reduction, but although their percentage of carbohydrates went up, the amount was reduced by 17% (because they were eating fewer calories, they were eating less carbohydrate and fat).
This is the first time, to my knowledge, that a low-carb diet has been pitted against a weight loss medication. In this case, the low-carb diet did as well as the medication for weight loss, with the additional benefit of better blood pressure and medication reduction, and avoiding side effects from the medication.
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