It is somewhat difficult to separate the concepts and practices of detoxification from fasting as they both accomplish a similar end, in sometimes different ways. Fasting is a method of detoxification, and most would say the most effective. Although, some forms of fasting can be extreme.
Toxicity is of much concern at this time as the world is very polluted and there is no place on planet Earth that hasn't been touched by our pollution created by our consumerism and economic model of wastefulness. Every year there are thousands of new and stronger chemicals, polluting our land, food, air and water. These chemicals come from such sources as the chemical industry, pharmaceutical industry, radiation and nuclear power. We ingest these chemicals, use more drugs of all kinds, eat more sugar and manufactured foods which are highly processed, and abuse ourselves with over the counter medications. Cancer and cardiovascular disease, top killers of many people are preventable. A wide range of symptoms from living a toxic life can show up as headaches, fatigue, pains, coughs, gastrointestinal problems, and immune weakness. Arthritis, allergies, obesity, and many skin problems are still others.
Internally our bodies produce toxins, in the form of waste, through normal functions. The waste that is produced from food once cells have made use of it, bodily activities generate substances that need to be eliminated as well. Free radicals are another type of biochemical toxins. When these toxins are not eliminated properly, they can cause irritation or inflammation, blocking normal functions on a cellular level. Microbes like intestinal bacteria, foreign bacteria, yeasts, and parasites, which can live in us due to poor lifestyle choices, produce waste as well that our bodies have to take care of.
Besides the chemical toxins our bodies carry around our thoughts and emotions or stress itself can generate toxins. The more angry, more negative someone is, the more toxic they become. The elimination of toxins is essential to health, but some of our bodies have more toxins than they can handle effectively. A normal functioning body was can handle a particular level of toxins, but the concern is with excess of toxins. This excess can come from a reduction in the processes of elimination toxins allowing them to accumulate or ingesting more than the body can handle. This is why we need to Detoxify on a regular basis.
Some books to help you to better understand Detoxification...
The Detox Book: How to Detoxify Your Body to Improve Your Health, Stop Disease, and Reverse Aging, 2nd Edition by Bruce Fife
Detoxification - All you need to know to recharge, renew and rejuvenate your body, mind and spirit! by Linda R. Page
Natural Detoxification, Updated and Expanded Edition by Jacqueline Krohn and Francis Taylor
The New Detox Diet: The Complete Guide for Lifelong Vitality With Recipes, Menus, and Detox Plans by Elson Haas and Daniella Chace
7-Day Detox Miracle, Revised 2nd Edition: Revitalize Your Mind and Body with This Safe and Effective Life-Enhancing Program by Peter Bennett, Sara Faye, and Stephen Barrie
Herbs for Detoxification by C.J. Puotinen
Dr. Jensen's Guide to Diet and Detoxification : Healthy Secrets from Around the World by Bernard Jensen