Do you capitalize breakfast and lunch?

Simple answer: Maybe. It honestly depends on what your writing and if its a proper noun or not. If its a proper noun then you capitalize it all the time. I'm referring to names and such, hence the reason David is always capitalized. But other nouns like 'he' are capitalized if at the beginning of the sentence but aren't if they are found in the middle or end of the sentence.

Ex.

He is a good guy

After the walk, he bought her some ice cream.