What is good health? -- Why is it important to have a healthy diet? -- What can exercise do for you? -- How does hygiene affect your health? -- What happens to your body when you sleep? -- What is pain? -- How does the body defend against germs? -- How does homeostasis protect your body? -- How does disease spread? -- What are common childhood diseases? -- What causes allergies and asthma? -- What are some different types of medicines? -- Why do diabetics need insulin? -- What are autoimmune diseases? -- How does heart disease develop? -- What is cancer? -- How do cigarettes and alcohol harm your body? -- Why is too much sunshine dangerous to your health? -- How do thoughts and feelings affect your health? -- What are eating disorders? -- Health careers -- Young scientists at work -- Take a health survey -- Fast facts.