The most healthy food is always the food that is in season. Nature has invented seasonal food so that you do not get bored of what you eat.

When you buy food from your local market, ask the farmer what food is in season right now.

You can also find a lot of valuable information on the Internet, so for the U.K., for example, you will find a list of seasonal food on Eat The Seasons.

A hint for overstressed managers: "The blackberry season spans the end of summer and the beginning of autumn and their usage can be adapted accordingly."