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I came across a 2003 article in the Harvard Gazette concerning a 12-week low-fat vs. low-carb study. Here's the link: http://www.news.harvard.edu/gazette/2003/10.23/03-lowcarb.htmlHere's the summary:
Greene et al. studied participants consuming one of three diet regimens over 12 weeks: a low-fat diet, a low-carbohydrate diet with the same number of calories, and a low-carbohydrate diet with 300 extra calories per day. The researchers found that the low fat group lost 17 pounds on average, the low carbohydrate group eating the same number of calories lost 23 pounds, and the low-carbohydrate group eating more calories lost 20 pounds.
This study wasn't published in a journal, because the findings were statistically insignificant. With such large difference in the group means, that indicates there was a high degree of individual variation within each of the three groups, and the high variation within each group was greater than the variation between the groups. E.g., there were some people in each of the groups who lost a lot more weight than others in their groups, mixed with some that didn't lose much, and in the low-carb groups there were likely one or two extreme outliers who brought the group mean down. However, given the sample-size, the overall variation in weight change between the groups wasn't different (probably at the 0.05 level, using an ANOVA). What adds to the statistical insignificance is that the only reported metric was weight; important, but finding significance between groups based on weight and finding it based on lean body mass tissue are two different things. I'm assuming that this wasn't reported, because there was less of an effect-size than with weight. The article states that the researcher did this study as a precursor to a larger study, but I couldn't find any kind of follow up. Does anyone know about what else she's done since 2003? Thanks in advance.
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