diary, dairy

Diary or diary means a book used to record the personal events of the day--
She wants a diary for her birthday.
She has a blue diary, with a little key.

Diary also means such a daily record in general--
This diary makes an important historical record.
He keeps a diary, full of the details of his days.
Her diary became a historical record, read by many students.

Dairy or dairy means a farm for milk cows, or a place where milk is bottled--
When we drive by the dairy, look for the cows.
Dairy also means a place where cheese and butter are made or sold--
We stopped at the dairy and bought some fresh butter and cheese.

Dairy also describes products made of milk--
Dairy products are part of a healthy diet.
Milk, cheese, yogurt, and butter are all dairy products.

Now that you know that, you can say--
"He records what he eats in his diary, including  dairy products, fruits and vegetables, and meat."