I think the most challenging thing is always being prepared with healthy food options. So time is probably the biggest problem for me, as well as not being forgetful. Often I forget my lunch, water bottle, vitamins or granola bars when I leave my house. Then I end up starving and choosing a not so healthy option. I try really hard to make sure that I have packed my food the night before, motivate myself to lug it around the city with me and have the groceries on hand to make appetizing food. I also try to incorporate my low cal foods with the foods my children eat, this way I can create a lifestyle (eventually after losing the weight, we will all eat the same things).