My cycle is always very regular. I stopped eating meat about two weeks ago, and my period is several days late, which has never happened before. I use birth control and I also have taken three pregnancy tests just in case which have been negative. Yes, any drastic change in eating habits can affect menses. Give it a few months and your body will settle into its rhythm again yes, any dramatic eating habit like that can change your period. Also exercising more can also change your cycle. You are fine. If it doesn't come until a longtime when it should consult a doctor and just make sure that everything is all right. | 