some things to consider:
- a pound of fat is about 3,500 calories. So in one week of 500 calories deficit every day you lose 1 pound (this isn't really true, but you get the general idea)
- salt (sodium) makes your body retain more water. Water is heavy and just eating less salted food will make you lighter, but keep same amount of fat. On the other hand, eating more salt will make you heavier.
- muscles are heavy (but not unhealthy like fat). On the upside, muscles also burn calories when in "rest". With lot of muscles you burn more even when doing nothing.
- all processed foods more or less destroy or minimize actual nutrients (vitamins, fiber, potassium). The less processed you eat, the better. Eat fruits and raw vegetables, plain yogurt (I know this is slightly processed, but nothing compared to McDonalds), some milk, cheese, fish. 1,000 calories in apples are much different than 1,000 calories in soda. Turn that apple into juice (no fiber) and it will be almost as bad as soda from a point of fattening you.
- Samsung phones have a Health app that can track your food and the nutrients in them (there sure are other apps). enter the food as you eat it (not after you already ate it, because you are more likely not to eat that donut when you see how many empty calories it has)