Bottom line: eat as healthy as possible & stay away from junk food.
Here are some essential oils that can help with fungal issues:
1) Tea Tree
6) Black Pepper
7) Cinnamon Bark
Most times you can make a blend in a carrier oil to apply to the body. Very few of these can be taken internally. Although I'm against that, it can prove useful, but be very, very cautious & consult a professional aromatherapist for guidance.