If you eat regularly every 2-3 hours, but every now and then you go a day without eating.. is that enough to slow down your metabolism? When I am at work, I "graze" the whole time I am there. But on my days off, I'm too sick and tired, and have no appetite. My job is very stressful, so on my days off, it takes a lot to recuperate. I combat migraines, and I don't usually feel like eating very much when I'm nauseated. I will just have bites here and there. Then the next day, I usually bounce back and eat normally again. How many days of fasting or eating very little would it take before it affected your metabolism?