the infection—the agents treat only the feverish symptom, not the causative pathogen. Likewise, diabetes drugs treat only the symptom of high blood glucose, not the cause of type 2 diabetes.
At present, the root causes of most chronic diseases are still elusive. Both genetic and environmental factors are known to play pivotal roles in etiologies of chronic diseases. Chronic diseases are often related to gene mutations. A single gene mutation rarely causes chronic disease; although people who carry a hereditary mutated gene may be at an elevated risk, it does not mean that they will inevitably suffer from the disease. Environmental factors are known to affect epigenetics (how our genes interact with the environment) as well as trigger the expression of predisposed hereditary genes. A nutrient-deficient diet and an unhealthy lifestyle are by far the two most important environmental factors associated with the causes of a host of chronic diseases. Conversely, a nutrient-rich diet and a healthy lifestyle can stave off chronic diseases.
You may have browsed through the internet or read a newspaper and found an article claiming that vitamins are effective in treating diseases. Yet several months later, you may have seen another news report make the opposite claim, suggesting that vitamins are not only useless but also possibly harmful to health. You might not know what to believe anymore. I am certain many people feel this way. Nowadays, information is readily available on the internet. With just a few keystrokes, you can find ample health-related data about vitamins and essential elements. Nevertheless, it is difficult to sort through all the available findings to build a reliable knowledge base that will improve your health and that of your loved ones. The aim of this book is to provide you with easily accessible, evidence-based knowledge about vitamins and essential elements for the prevention and treatment of chronic diseases.
Before you dive into the contents of the book, you need to know how clinical data are generated. First, several kinds of clinical studies exist. Let us start with the simplest one. A doctor prescribes vitamins to treat a patient suffering from a disease, and after taking vitamins for a few months, the patient recovers from the illness. The doctor publishes his findings in a scientific journal. This is called a “case study.” If the doctor prescribes vitamins to a group of patients rather than a single patient and publishes his findings in a scientific journal, that is called an “observational study.” On the other hand, if the same doctor publishes the findings of a study in which he divides his patients into two groups, in which one group receives vitamins and the other group receives a placebo, and neither the doctor nor the patients know who is taking vitamins and who is taking the placebo, that is called a “randomized controlled trial.”
Many doctors and scientists worldwide are conducting clinical studies to test the effectiveness of vitamins for preventing or treating chronic diseases. For example, in the past 10 years, at least eight clinical studies have been published on the use of vitamin D for the prevention of osteoporosis. Although their topics and design might have been similar, these eight clinical studies produced different results and conclusions due to factors like patient selection, dosage, environment, and the like. Can vitamin D prevent osteoporosis? Of those eight clinical studies, which one should you believe?
Fortunately, a statistical method known as meta-analysis has been widely used to assess the efficacy of pharmaceutical agents in treating diseases. In the case of the abovementioned example, a meta-analysis would combine all the clinical data obtained from those eight clinical studies, excluding the data deemed to be biased, and analyze the remainder of the combined data to reach a statistical conclusion on whether vitamin D can or cannot prevent osteoporosis. Meta-analysis is currently the most reliable method for assessing the efficacy of vitamins or essential elements in preventing or treating chronic diseases. All the information on how vitamins and essential elements prevent and treat chronic diseases in this book is based solely on meta-analyses published in peer-reviewed scientific journals, not any single clinical study report.
This book contains five parts. Part 1 contains a brief history of the discovery of each of the 13 essential vitamins—namely, vitamin A, vitamin B1, vitamin B2, vitamin B3, vitamin B5, vitamin B6, vitamin B7, vitamin B9, vitamin B12, vitamin C, vitamin D, vitamin E, and vitamin K. Part 2 covers essential elements, including the five essential elements—calcium, potassium, sodium, magnesium, and phosphorus—as well as the eight essential trace elements, which are iron, zinc, manganese, copper, molybdenum, iodine, chromium, and selenium. Both parts 1 and 2 also present meta-analytic evidence of the efficacy of each vitamin/essential element in the prevention and treatment of diseases, its recommended daily allowance, and best food sources of it. Part 3 provides important secrets for staying healthy. These include an explanation of how sugar makes you fat, why patients with autoimmune diseases should not eat meat, and how exercise benefits the brain. Part 4 provides meta-analytic evidence of which vitamins and essential elements should be taken to prevent and/or treat 75 chronic diseases and conditions, including lung cancer, breast cancer, colorectal cancer, prostate cancer, endometrial cancer, blood cancer, bladder cancer, glioma, diabetes, stroke, heart disease, cataracts, hypertension, Alzheimer’s disease, osteoporosis, arthritis, hepatitis C, fatty liver disease, Parkinson’s disease, sleep apnea, and others. Part 5 summarizes the clinically proven remedies for preventing and treating the 75 chronic diseases and conditions presented in part 4.
For the purpose of easy reference, all vitamins, essential elements, secrets for staying healthy, and diseases in this book have been assigned a specific chapter number: vitamins are numbered from 1 to 13, essential elements from 14 to 27, secrets for staying healthy from 28 to 36, and diseases from 37 to 111. For example, vitamin A is 1, calcium is 14, and Alzheimer’s disease is 37.
Author’s disclaimer: The book provides readers with relevant health information about vitamins and essential elements, but it does not intend to be a substitute for any medical advice given to readers by health-care professionals. Efficacies of vitamins and essential elements in preventing or treating diseases may vary greatly among individuals. Recommendations from the book should not replace any nutrient-balanced diets or prescribed medications.
Vitamins are essential nutrients that the body does not make; therefore, they have to be obtained from foods. Some vitamins are derived from animal-based foods, while others are from plant-based foods. Only by consuming nutrient-balanced foods can one obtain sufficient amounts of all 13 vitamins—vitamin A, vitamin B1, vitamin B2, vitamin B3, vitamin B5, vitamin B6, vitamin B7, vitamin B9, vitamin B12, vitamin C, vitamin D, vitamin E, and vitamin K—to maintain good health. These 13 vitamins are distributed to various organs and tissues, and each one is involved in a multitude of essential physiological functions in the body. Vitamin literally means “being vital for life.”
Vitamin A is also known as the anti–dry eye vitamin. In 2000 BCE, physicians in ancient Egypt and Greece already knew that beef liver could cure night blindness. Of course, they had no way of knowing that this was because beef liver contains high amounts of vitamin A. In 1913, Lafayette Mendel and Thomas Osborne were able to isolate a “lipid-soluble” substance from chicken eggs and fish liver and called it vitamin A. In 1930, the chemical structure of vitamin A was identified as retinol.
Vitamin A enhances vision, allowing us to differentiate people from objects in our surroundings in dim light. In the eye, vitamin A binds to opsin, a photosensitive protein, to form rhodopsin. The photosensitivity of rhodopsin essentially establishes our eyesight and vision.
Vitamin
