The flesh and the rind (which has a stronger taste, and is often called the 'zest', are used in cooking. The acid of the lemon is often used in cooking to balance fatty or sugary foods. The juice of the lemon is about 5% to 6% citric acid, and like all acids, it therefore has a sour taste.

Lemons were not grown in Europe until the 15th century. Then it was spread to the Americas in 1493 when Christopher Columbus took lemon seeds on his voyages.

In 1747, James Lind's experimented on sailors suffering from scurvy, adding lemon juice to their diets. This helped them to recover, although at that time they did not know it was due to the lemon's vitamin C content, and any other similar fruit would do the same (e.g. the limes used in the british navy).

Lemon juice is also used as a short-term preservative on certain foods that tend to oxidise and turn brown after being sliced, such as apples, bananas, and avocados, where its acid stops the enzymes that cause browning from working.

Lemon juice and rind are used to make marmalade and lemon curd as well as lemon drinks. Lemon zest is used to add flavour to baked foods.

The leaves of the lemon tree are used to make a tea, and for preparing cooked meat and seafood.