I have been vegan for 12 years. Is there a vegan alternative to the Atkins diet?

When I first became vegan I became very thin. Over the last four years I have put on some weight due to eating too many tortilla chips and avocados, i think and maybe due to my age. My boyfriend is Korean, and says every vegan he knows is fat! (including his own dad!) I became vegan to loose weight and it worked for a long time, but will never go back to eating meat again. He eats steaks every day and is skinny! What is the vegan equivalent to the atkins diet?