Your menu is your business. As long as you are not starving yourself, or turning yourself into a blimp, no one has any business criticising what you are eating. You didn't mention your gender, height, or body type. For a tall male, with a muscular frame, your current weight may be a little high, but not too bad. For a female, your current weight is too high, but either way, you do mention that you have been restricting what you eat. I assume that's to bring your weight down to a healthier level--good for you! Dieting is hard. I am absolutely flabbergasted that any adult teacher would think someone whose overweight should put on more weight. Tell them you are a legal adult and they don't get a vote on what goes in your mouth, and that they are not to bother you about it any more.
Now, go enjoy your own food choices! 
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If a man does not keep pace with his companions, perhaps it is because he hears a different drummer.
Let him step to the music which he hears, however measured, or far away.--Henry David Thoreau