deficit, adequate protein, and exercise, they should not be used as evidence for or against the
ketogenic diet.
At more moderate caloric levels, one early study has shown that fat loss increased as
carbohydrate intake decreased. Two recent studies showed no statistically significant
differences, but there was a trend towards greater fat loss and less muscle loss as carbohydrate
quantity came down. An important note is the high degree of variability in subject response to
the different diets. None of these studies provided what this author considers to be adequate
amounts of protein.
Perhaps the proper conclusion to be drawn from these studies is the variety of approaches
which can all yield good results. At the very least, a properly designed ketogenic diet with
adequate protein appears to give no worse results than a non-ketogenic diet with a similar caloric
intake. Some research suggests that it may give better results. Anecdotally many individuals
report better maintenance of lean body mass for a SKD/CKD compared to a more traditional diet.
This is not universal and others have noted greater LBM losses on a ketogenic diet.
The definitive study comparing a ketogenic to a non-ketogenic diet has yet to be performed.
It would compare fat loss/muscle loss for a ketogenic diet at 10-20% below maintenance calories,
with adequate protein, and weight training to a higher carbohydrate diet with the same calories,
protein intake, and exercise.
Ultimately, fat loss depends on expending more calories than are consumed. Some
individuals have difficulty restricting calories on a high-carbohydrate diet. If lowering
carbohydrates and increasing dietary fat increases satiety, and makes it easier to control
calories, then that may be the better dietary choice. Other potential pros and cons of the
ketogenic diet are discussed in the next chapter.
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