What is a missed period?

This is what i eat in a typical day - is it not enough, and causing a missed period?

• Last year, i stopping having periods because i was slightly underweight. This year, i reached a healthy weight again and i have maintained it. My periods started again two months ago, and they were perfectly regular - the second arriving 28 days after the first. This month, i was due on the 25th April, but my period hasn't come all week. In February, when i got my period back, i had been eating two meals a day, and a total of about 1600 to 1700 calories. In March, i began eating just lots of food in the evening, just one meal a day, and about 1300 to 1500 calories. I still had a regular period on time, though. Now, in April, after nearly two months of eating one (large) lot of food a day, my period hasn't arrived. Is it because of this? This is what i eat in a typical day - is this little enough to cause a missed period? Bare in mind, if it's relevant, that i eat this all at once within about an hour. I only eat once every 24 hours. Large salad, 150 to 200g of skinless chicken breast, fish OR sea food, like prawns 300 to 400g of carbs, usually fruited, malted bread, sometimes pasta, cereal or rice. Thanks.... I just don't want to end up amenhorreic (not having periods) like last year when i was too thin. =D

• Answer:

  Luv, that doesn't sound like enough food to me. And I always see you asking food-related questions and you've already had health issues (like not having periods for a while) so sweetie, please start eating properly. I'm sure you're a gorgeous girl inside and out.