Millions of Americans suffer with allergies, yet medicine has yet to determine exactly what causes a person to be allergic. In this comprehensive book, naturopath Chris D. Meletis examines a wide-range of allergies, including those to foodstuffs, dust and other airborne allergens, and materials like latex and chemicals. He explores theories of why allergies occur and are rising, including the "hygiene hypothesis," which argues that overbathing and overuse of antibiotics and antibacterial agents means our immune systems never build up the necessary resistance to these substances when we are young.