Intermittent fasting. These days I only have one meal a day
I had a month off work recently (unrelated to the pandemic), which I spent learning programming. During this time I never ate lunch, only a small breakfast and a normal supper. But now that I'm back at work and I'm on my feet all day, I have to eat, otherwise I get super hungry, lightheaded and generally lethargic. But I've discovered that I don't have to eat very much before I'm back to normal.
I lost a lot of weight, feel much better, and save money and time every day now.
An important caveat to bear in mind is that not all fasting diets entail calorie restriction (though many often do); it is calorie restriction that is linked to reduced inflammation and possible benefits to lifespan.
The thought of food usually makes me queasy before around noon. So I naturally slipped into intermittent fasting before I knew what it was.