Certainly there is nothing wrong with the study of nutrition or the desire to be healthy; but we must always keep in mind that health is not an end in itself. It is a means to an end. We do not exist to be healthy. We exist to seek God so that we might know Him through Jesus Christ and fellowship with Him throughout eternity. According to the Westminster Catechism, the chief end of man is to “glorify God and enjoy Him forever,” not to find the right diet and live a long healthy life on the earth.

In Philippians 3:18-21, Paul said, "For many walk, of whom I often told you, and now tell you even weeping, that they are enemies of the cross of Christ, whose end is destruction, whose god is their appetite, and whose glory is in their shame, who set their minds on earthly things. For our citizenship is in heaven, from which also we eagerly wait for a Savior, the Lord Jesus Christ; who will transform the body of our humble state into conformity with the body of His glory, by the exertion of the power that He has even to subject all things to Himself."

In this passage, Paul weeps over enemies of the cross of Christ. He then singles out two characteristics of them that are relevant to the discussion of this book. One, their god is their appetite (literally, belly). Two, they set their mind on earthly things.

What does Paul mean when he says their god is their appetite, or belly? At the very least he means that they serve their belly, not Christ. They live for their appetite, not for Christ. Their stomach controls their decisions, not Christ. It seems that there are two ways to serve one’s belly and be governed by it: through gluttony (which is probably Paul’s meaning here) or through the legalistic self-denial of food that Paul speaks of in Colossians 2:16-23. It is the latter that has given root to the doctrines of Nutritianity. I have given the name “nutrition Pharisee” to those who promote a legalistic self-denial of foods because, like the Pharisees of old, they turn their diet into an external righteousness that feeds their pride and fosters a judgmental spirit toward others.

The glutton and the nutrition Pharisee seem to be very different at first glance, but in reality, they are quite similar. The glutton is a slave to his belly because he is controlled by his insatiable appetite for food and drink. He is not accustomed to abstaining from anything he enjoys. If he likes it, he takes it, in large quantities. He doesn’t merely enjoy the liberty to eat whatever God has created. He indulges in the liberty. His goal is to reduce the time that elapses between the birth of a desire and its fulfillment. He is addicted to food and drink, and like anyone with an addiction, he gets cranky when he can’t get his fix.

The nutrition Pharisee also makes a god of her belly. She is a slave to her belly (or body) because she is controlled by health concerns. (I use the female pronoun because women generally purchase and prepare the food. However, the dangers apply to men as much as the dangers of gluttony apply to women.) In many ways, the nutrition Pharisee’s life also revolves around food. She worries about whether she is being healthy enough. She makes a sacrifice of time and money for her belly. It takes time to research all the latest findings to discover the healthiest food. It also usually costs more money to buy that food, but she is willing to make that sacrifice for something so important. It is her tithe to her god.

Often, her friendships are limited by her devotion to her god. It is hard for her to fellowship with those who are not as committed to health as she is. She finds it difficult to accept invitations to dinner, since she would either be forced to eat the “unholy” food that is prepared by her “ignorant” friends or she would have to awkwardly bring her own food. She also finds it difficult to invite others for dinner, because she cannot in good conscience fix the kind of food that her friends like to eat, and it is often expensive to fix for a big group what she likes to eat. What do you call something that has the power to govern your thoughts, time, money, and friendships and which can bless you when you obey its rules and curse you when you don’t? You call it God.

Both the nutrition Pharisee and the glutton serve self. Whereas the Pharisee serves self by denying herself foods so that she can be proud, the glutton serves self by giving his flesh whatever it wants. Both have pride. The Pharisee has pride that she is not like undisciplined people. The glutton has pride that he is not encumbered by the silly rules of the Pharisee.

Whereas the sin of the glutton is easily spotted, the sin of the Pharisee is not as obvious because it is concealed beneath an external appearance of religious conviction. She appears to herself and to many around her to be righteous and devout. Unlike the glutton, she is not addicted to sweets and treats. She has control in these areas. Furthermore, she offers biblical reasons for her diet. She says that she is being a good steward of the body God has given her and “taking care of the temple of the Lord.”