And I will put enmity between you and the woman, and between your offspring and hers; he will crush your head, and you will strike his heel. Gen. 3:15, NIV.

The human body consists of several important organ systems, each of which carries on a special function. The one most extensively studied in recent years has been the immune system.

Like a nation's Department of Defense, our immune system protects against foreign invaders and helps maintain national peace. While the armed forces defend their country, the immune system employs B lymphocytes, T lymphocytes, phagocytes (neutrophils, monocytes, and macrophages), killer cells, and natural killer cells to do the same. Macrophages are the "national guards" stationed throughout our bodies, while the other types circulate in the blood to keep us healthy.

When we put harmful things into our bodies, we destroy God's temple. For example, in Leviticus 3:17, God says: "This is a lasting ordinance for the generations to come, wherever you live: You must not eat any fat or any blood" (NIV). Science now knows that a high-fat diet contributes to heart attacks, strokes, several types of cancer, as well as immune cell destruction. A simple way to illustrate destructive health habits is with the acronym FAT CAT. F stands for fatty and highly processed foods, A for anxiety and stress, and T for toxicity—unhealthy exposure to toxic chemicals and environment. CAT represents three legalized drugs: caffeine and caffeinated drinks, alcohol, and tobacco. All these factors harm our immune system, and as a result destroy our bodies.

To maintain a healthy immune system, we need to stay away from the FAT CAT and nourish the immune cells with wholesome, unrefined foods—fresh vegetables, fresh fruits, whole grains, and legumes—as close to their natural state as possible. We also need pure water externally and internally, and regular, meaningful, outdoor exercise. Above all, trusting in God, reading the Bible and inspirational literature, and sharing our faith will fill us with hope, joy, and direction in life.

Just as your body's healthy immune system combats disease, a healthy spiritual immune system fights off temptation and sin. What destroys your spiritual immune system? Lack of Bible study, prayer, and meditation, along with selfishness, pride, intemperance, and a negative attitude.

A great struggle is going on between Christ and Satan. What are you doing to make sure your spiritual immune system is strong and healthy?

Used by permission of Health Ministries, North American Division of Seventh-day Adventists.