We find one helpful suggestion in, of all places, the pages of Martin Heidegger's philosophical masterwork Being and Time — at least part of which is concerned with exploring the multitude of ways that people flee from their mortality.
All of us know, intellectually, that we will die. But Heidegger suggests that we only come to grasp it existentially in the mood of anxiety. In anxiety, the average everyday pursuits that normally occupy and absorb us recede and appear drained of meaning. The arbitrariness of our lives and the world into which we've been thrown light up and we are left adrift, aware as we otherwise rarely are that the world and our lives hover over an abyss of nothingness into which we could tumble at any moment.
It can be a chilling experience — and so we flee from it, throwing ourselves more fully and more deeply into the world, finding comfort and solace in its seeming (but deceptive) solidity. Addiction and obsession are particularly intense forms of this fleeing into the world, Heidegger proposes, since they turn one particular entity within the world into the nearly exclusive focus of our existence.
But if that's the case, then an obsession with food — the consumption of which assimilates worldly entities into our very selves, causing a visceral feeling of fullness, which compensates for the haunting perception of existential emptiness that accompanies anxiety — may be among the most potent ways to ward off an existential crisis. At least for a brief period of time.
This doesn't explain why the United States would have more existential crises — and higher rates of obesity — than other places. But then again, much of the world appears to be catching up to us, perhaps indicating that, as with so many other aspects of advanced capitalism and modernity, America merely got here first.