According to BroBible.com, here are some ways to discreetly hint to your girlfriend that she’s getting fat:
Improve YOUR fitness routine – You can’t tell her to get fit. You’ll need to lead by example.
Eat better –By stocking the fridge with healthy stuff, you’ll send a healthy message, without laying on a guilt trip.
Rethink “Date Night” – Getting out there and being active is actually more fun than sitting on the sofa with a movie and a bag of chips.
Plan a bikini vacation – A beach vacation on her calendar will inspire her to take care of business.