[jeremysmyth]

Alcohol doesn't contain sugar. Rather, it replaces glucose in the blood and can be used directly as a fuel without any conversion.

This is unlike in low-carb diets, where fat must be converted to a fuel (via gluconeogenesis) before cells can use it as energy, and this conversion itself takes energy.

Effectively, alcohol reduces the benefit of low-carb diets but doesn't necessarily increase the insulin response as would a high-sugar diet.