A LOAF OF BREAD

My colour is brown but can also be white 
I can be eaten during the day and also at night 
For a simple snack I am spread with butter and jam 
Sometimes I have a filling cheese or ham 

During the winter to the toaster I would go 
I am my friends a loaf of bread just so you know 
I vary in size be it medium or thick 
Don't eat too much of me or you will be sick 

A loaf of bread's life is great as you can see 
I have to go now as Johnny wants me for his tea