Vitamin D Prescription: The Healing Power of the Sun & How It Can Save Your Life Dr. Eric Madrid in his illuminating new book, Vitamin D Prescription, claims up to 80% of us are deficient in vitamin D from children to seniors. Vitamin D not only builds strong bones, but it can help prevent or control diseases such as diabetes, high blood pressure, lupus, and even cancer. Madrid urges readers to have their blood vitamin D levels checked by their physicians and to supplement with vitamin D pills. He also advises to limit the sunscreen and soak up the healthy rays of the sun instead. Filled with thought-provoking research studies, personal anecdotes and case histories, Vitamin D Prescription is meant to be an easy-to-read and informative book about the healing powers of this astonishing vitamin.