Your brain is like your stomach
This is an idea I had for a while where I feel that your brain is kind of similar to your stomach in a way. When you eat the quality of the food can effect your mood eating a nice filling dinner Like Chicken, Mashed potatoes, and collard greens (My mouth is watering just thinking about it). Can leave you satisfied, mean while snacking on chips won't really fill you up at all.
Now there is nothing wrong with chips it's ok to snack on them heck I did so earlier, but you can't just live off of chips forever.
I feel your brain is the same way you can feed it engaging stuff, or just stuff you really enjoy like a hobby, hanging out with friends etc, but you can also just watch a bunch of cat videos, and while watching cat videos is perfectly find you can't just live off of it.
There is also another way these things connect which is some stuff is just down right bad for you and your body. Example pure sewage is something that no human being should ever consume that's undeniably bad for you.
Same with how there are somethings that are horrible for your brain like ragebait content online is just bad for you and provide no benefits at all except ruining your day.
All in all take care of your stomach and brain both are important and both will thank you!