The world situation might make one feel anxious, sad, concerned, but not depression. Depression happens regardless of the state of the world or someone's life circumstances.
It's when someone internalizes feelings. The outside world disappears or becomes unimportant. Very dangerous.
Many try to self-medicate to stop the anguish, sadness.
Many things have been tried but nothing universal has been found. At one time depression was seen as in the same category with illnesses like psychosis. Fortunately not today.
A very low carb diet might kill you. Carbs are used for brain food. Cutting back to a healthy carb intake is fine but your body needs carbs.
I have to be careful because I am a carboholic. A regular cookie monster. Our bodies like cheap energy. By that I mean foods easy to convert to energy then fat. Sugar, alcohol, carbs.