It really was only a matter of time until a longitudinal study on a massive scale, such as this one in the European Journal of Clinical Nutrition, came out to back up what common sense told us was unhealthy. That being, that artificial, gross manipulations of diet aren’t great for you. In fact, they may just shorten your life span a bit. This study was published online in advance at the end of 2006, but didn’t come to my attention until right this minute (its now free online).
The study, a collaboration between researchers in Greece and at Harvard, attempts to evaluate the effects of a low carb-high protein diet on mortality (likelihood of death.) To this effect they followed 22,944 healthy adults from 1993 to 2003 and assessed diet through validated questionnaires. These participants were distributed into ‘deciles’ or categories based on their diet.
The quick-and-dirty explanation of the results is that higher intakes of carbohydrates was associated with a REDUCTION in mortality, however differences in protein intake did not affect mortality. The most powerful predictor of higher mortality was the combination of a low carb-high protein diet, which was significantly correlated with increases in mortality from cancer and heart disease.
Now these results shouldn’t be interpreted to mean that all short-term applications of a low carb/high protein diet are unhealthy, only that for protracted periods of time such a diet has a negative effect.