At 6 mo , the weight loss in the vegan group ( -7.5 % 4.5 % ) was significantly different from the omnivorous ( -3.1 % 3.6 % ; P = 0.03 ) , semi-vegetarian ( -3.2 % 3.8 % ; P = 0.03 ) , and pesco-vegetarian ( -3.2 % 3.4 % ; P = 0.03 ) groups .