The holy period requires Muslims to fast, but Diaby has insisted that if he fails to avoid food at times because of his pre-season preparations, he will make up for it later in the year.
In an interview with TheFA.com, Diaby said: "This is the most difficult moment to fast, because of the long days, because of the heat.
"It is really difficult to fast at the moment, during pre-season. Some players can handle it – it is different from one player to another.
"All the days I miss during Ramadan I make up during the rest of the year. For example when I have days off or a light session I can fast, but when we have a hard session or a match, I don't fast."
Ramadan ends on July 28.