Ketogenic diets do not negatively impact basal metabolic rate and are associated with equivalent or greater weight loss than low-fat diets.

“all of the studies that have been done with ketogenic diets people lose an equivalent amount of weight or more relative to low to low fat diets and if we were really inducing hypothyroidism with a ketogenic diet the basal metabolic rate would go down and they would not lose weight they would gain weight or this not be the same right there so the fact that you know by all evidence that we can see it really appears that basal metabolic rates are not changing in a negative way they are not going down on ketogenic diets some people would argue they're going up”