Will the Nagano Tonic be equally effective if belly fat accumulation is due to liver disease?

This is the case. In a sense, the accumulated belly fat is akin to a garbage dump. What is important is for the garbage to be removed and sent somewhere for storage away from human habitation. So the fact belly fat accumulates as a way of sequestering toxic materials, that does not mean it needs to remain within the body, if the fat can be cleared and the toxins eliminated through excretion in a steady fashion. This is a complex picture, of course, and may have trade-offs in getting some systemic exposure of unwanted materials along the way, but you cannot have your cake and eat it too. In all likelihood, the amount of fat is far in excess of what is needed to provide a repository for safekeeping of toxins on a day-to-day basis. So, in our analogy to the garbage dump, it is, in many respects, a kind of monument to past history of a person's exposure to negativity that need not be a permanent fixture in the body.