When I'm not pregnant, I maintain a healthy weight that some people would call thin (size 4ish, ~120 lbs at 5'4). When I exercised vigorously 6x a week (mostly cardio), I weighed `~100 lbs. DH eats the same *kinds* of foods that I do (albeit in drastically different portions), and would probably be called obese. He also works a more physical job than I do.
- I grew up in a household where everyone cared about nutrition. There was always a newspaper article about some aspect of nutrition taped to the fridge. I don't agree with everything I was taught by those articles, but it does mean that I think about everything I put into my body and how it's going to impact the workings of my body.
- At dinner time I fill half my plate with veggies. I don't go back for seconds of carbs or meat, if we're eating meat. We set our plates up differently from the outset.
- I don't eat after dinner. If I feel low blood sugary before bed, I might consider a glass of milk or a piece of fruit or some leftover salad. DH eats granola bars, leftover carbs or meat from dinner, a second plate of dinner, or ice cream.
- I don't skip meals. DH often misses breakfast and lunch, comes home and eats four sandwiches with meat and mayo and cheese, then has dinner with me, then gets hungry and eats another meal sized portion before bed.
- I don't see bread or crackers or bagels or muffins as a snack, and I don't eat bread without lean protein and veggies. I might have toast and egg and fruit or veg for breakfast, but I would not have bread and butter as a snack. Muffins are nice, but if I'm going to eat a whole bunch of white flour and sugar, I'd really rather just have a cookie or a doughnut.
- I don't drink anything but water, and very occasionally milk. When I drink a glass of milk, it's less than 250 mL/1 cup. DH drinks juice by the litre. I see this as a symptom of the larger problem about not thinking about everything that goes into his body.
- I am usually enrolled in some kind of fitness related class. This has been aquafit, ballet, yoga, hiking, running. It's always once a week, and so I get 1 hour of vigorous exercise (ok, excluding yoga) once a week. It encourages me to be more active in the rest of my time. DH drinks beer and plays video games in his off time, punctuated by a hike every couple of weeks.
- I let myself eat the "bad" foods I love, in moderation. Chocolate cake, gelato in the summer, yam fries and aioli, brie and baguette, tempura avocado. If there's a food I like, but isn't a favourite, and I know will do nothing good for my health, I skip it (ie. vanilla ice cream, non-yam-fries, cream sauces, potato chips - delicious, but not worth it to me).
- If we're going to eat out, I prefer Indian or Ethiopian restaurants where I order non-cream-based vegetarian curries, or pho or sushi places. DH prefers pizza, pasta, and burgers. When we do end up going to those pizza, pasta, and burger places, I hardly ever order pizza, pasta, or a burger.
I don't think this is obsessive, and I do it largely to prevent disease in later life and to feel good now. I am very worried about DH, but it's his body and his choice.