What does it mean to let for of the food? More correctly from a stoic point of view, the desire to eat is within our control. We can therefore counter the desire to eat, and go do something else. Easily said, not so easy to do, or is it? But the desire is always there, weak but there, sometimes strong but there. That feels like a craving, but what if it has a physical cause? Hyperinsulinema? Excess ghrelin? Adrenalin? Adrenalin is a natural response to stress, anxiety, even mild allergy, the body dumps out a bunch if adrenalin to deal with the issue, and adrenalin cause hunger through the re-feed cycle. So it is a natural effect to feel hunger from stress, anxiety, boredom, etc.
Now one more twist in all this. Sugar, or more exactly high blood glucose, and also high insulin are both relaxants. So we want to relax, we eat carbohydrates, the "comfort" foods. Now we know addiction is typically a cue-consume-benefit-want more (crave)-consume-cycle over again and over again-until we can stop problem. We get a benefit, we like the feeling, and this would not be a problem if we did not eat too much. There is the problem, we can be addicted and yet limit eating to a suitable amount, and not get clear of the problem, problem foods.
So letting go of the food is not what we must do, but let of desire to eat may be what is meant, in stoic terms. We must let go of the desires in general.
and about the net: http://www.psychologytoday.com/blog/food-junkie/201410/physician-shares-her-private-struggle-food-addiction
But then perhaps we are looking for the other thing when we need to:
Learn to become content with a minor amount of food.
Learn to become content with less food.
Learn to become content.
Stoic world view http://blogs.exeter.ac.uk/stoicismtoday/2014/10/25/the-stoic-love-of-community-by-matt-van-natta/