Constant joking about weight gain?

Did you ever feel like some people (coworkers, in my case) are really rooting for you to blow up and double your body weight? I started off on the lower side of healthy BMI and have always been very athletic and healthy. A large part of my job is physical (I'm a wildlife research biologist, so we do a lot of remote/physically demanding field work through the spring/summer/fall). From the time I told my coworkers I was pregnant (waited until about 17 weeks, but finally had to let it out since I'm due in July and it definitely affects field personnel planning this summer!), it's been near-constant "joking" about weight gain, hoping I double my body weight, blowing up, etc. and people are always dropping whatever junk food is in the office break room at my desk. Literally every day someone is putting a plate of cake, cinnamon rolls, donuts or whatever at my desk with some joking comment about "you probably need a few of these today." I pretty much never ate that crap before and I don't want to now, either! It doesn't seem mean-spirited but it's really starting to annoy me that everyone apparently thinks it'd be so hilarious to watch me get fat. I've actually said a few times now that I'm watching my diet & sugar intake, trying to continue eating whole & healthy for a healthy baby, not craving sweets, and ha ha guys, but seriously please stop with the junk food pushing already. No luck. I just end up throwing it away most of the time but it irks me to feel kind of disregarded and a little like the butt of a joke. I've gained a healthy amount (though it doesn't really show yet at 22 weeks) so there's really no excuse other than people just think it's funny. Side note, these are ALL male coworkers doing this (my office is almost all male). Am I overreacting to feel irritated, or do they just not get it or realize it's obnoxious? Do I just laugh and keep throwing shit away after they leave? Anyone else?