Eating is good and so is fasting.
While eating is certainly good, it is still good to fast as well.
As Christianity begins growing again, there will be questions about fasting. Should Christians fast today, for example. While eating is certainly good, it is still good to fast as well.
What is the meaning of fasting? It has to do with giving up what you want out of love and for the good. Imagine a friend who really enjoys eating but can't eat before a surgery. You're probably not going to eat anything she really enjoys in front of her. In fact, you might not eat anything in front of her in order to share in her anxious experience in love and friendship.
Christians fast in memory of how Jesus gave up food and drink to share in his experience with love as friends. Even people who aren't religious can fast, as seen in the surgical example above. Fasting in different ways makes sense to human empathy in general.