Fulvic acid is a compound found in soil that is used in gardening and landscaping to improve plant growth. It is also being promoted in supplement form by marketers who claim that it offers many health benefits including detoxification, better mineral absorption, anti-aging effects, and immune enhancement. I've seen nothing that indicates a scientific basis for any of this.
In evaluating sales pitches for the various methods of detoxification and other cleansing regimes described online and elsewhere, keep in mind that the body does a very good job of cleansing itself. If you stop putting toxins in and focus on good nutrition, regular exercise, and other healthy habits, you won't feel the need to buy any products or special devices to keep your system clean.
You can help the body rid itself of unwanted materials by drinking more water to increase urinary output, taking steam baths or saunas to promote sweating, adjusting diet and fiber intake to ensure regular eliminations, and getting enough aerobic activity to stimulate breathing. If your daily environmental exposures warrant it, taking milk thistle can help boost normal liver metabolism, aiding its important role in detoxification.
As far as mineral absorption is concerned, there's no reason to worry about this unless blood tests have revealed that you are deficient in some mineral. Despite claims from some marketers that the minerals in our foods are not bioavailable, the best way to ensure that you get all of these micronutrients is to eat a variety of fresh vegetables. I also recommend a good daily multivitamin/multimineral supplement for nutritional insurance.
Andrew Weil, M.D.