I believe it. The body desires homeostasis. It has mechanisms in place to keep you the same. An unhealthy standard American diet can foil those mechanisms, but I believe that a healthy, low-carb diet based on whole foods will allow those mechanisms to function.
When I start my weightlifting program soon, I'm planning to drink a pint of heavy cream every day for extra calories, to encourage my muscles to grow. It will be interesting to see if I experience much fat gain.