If a woman is extremely poorly nourished, her periods will almost certainly stop. A woman's body will not let her risk pregnancy if there is no food, if your body thinks you are starving it will not ovulate and won't menstruate. Athletes whose body mass contains very small amounts of fat sometimes find they stop having periods for this reason. Stress can do it also. But if you have a known lack of nutrition, you probably don't have to hunt around for other reasons like stress (unless of course you have both -- low calorie intake and also stress). Are you poorly nourished or are you possibly deliberately reducing your calorie intake? There are other ways to maintain a proper weight than by not eating.