How should I deal with my boyfriend constantly commenting about what I eat around him?

Recently my boyfriend has been putting extra pressure on me to lose weight, so if i eat too big of a portion or even have a bite of anything "bad" he will glare at or scold me. Now when I eat around him I'm on edge because I don't want to eat anything that might bring up the are you really serious about losing weight talk. We've discussed it and he's gotten better but he still will mention or comment on what I'm eating all the time. I am overweight but not morbidly obese, think Kelly Clarkson at her biggest. I've been talking about losing weight for a long time, I have no immediate health threats but is there really a good reason for him to be acting like this? Could there be something underlying here or is it really seem like a well intention attempt to help me be healthier?