In terms of diet, usually, but it's also used for alcohol and other things like exercise.
moderation
Any controlled amounts of anything is called moderation. You might drink alcohol in moderation, or exercise in moderation.
If you are getting fat, that is an indication that you are eating too much fattening food. Eat less.
Fattening foods!
none
No, not at all. Onions are one of good sources to negative calorie foods. Regarding to negative calorie foods, amount of calories used in the process of chewing and digesting is greater than the amount of calories contained in the food.
Fattening foods, sweets, and chips or junk foods...
It's more about the amount of calories than it is about stuff sugar or starch. For the same amount of calories they're just about equally fattening.
adequacy balance calorie control moderation variety
People believe, quite rightly, that they are fattening.
Not neccessarily, but it is common. Not necessarily. If the parents eat fattening foods, and do not exercise (probably the cause for the over-weightness of the parents), and the child eats lean foods, non-fattening foods, and exercises, the child will not be 'fat'.
Eat only the non fattening foods that are required to keep up a reasonable amount of energy and exercise regularly.