I heard that vitamin b12 can help with the tiredness. Anyone know if this is true? Or is it more of a placebo effect?

My neighbor takes it for that very reason.  Her doctor prescripted it for tiredness.

B12 deficiency causes prenicious anemia which lowers red blood cells and thus causes tiredness like any anemia.  This deficiency however is caused if your stomach/intestines lack the ability to absorb B12.  My cousin has to take B12 shots for this.

I asked my pharmacist when I went to get my prescription filled and she recommended a B50 complex. It felt like it helped today. We'll see if it lasts.