Light plays a big role in our health in general and particularly with mood stability. The study of the impact of light and circadian rhythms on health is called chronobiology. The Center for Environmental Therapeutics (CET) is involved with international research in this. Their website connects to research, products to work with light, practitioners and general information.
The Centre for Chronobiology has published a book entitled Chronotherapies for Affective Disorders written by Anna Wirz-Justice, Francesco Benedetti and Michael Terman.
This article describes research carried out at the University of British Columbia where light therapy was found to be an effective treatment for depression.
We are all concerned about energy efficiency and LED lightbulbs have become very popular. A German scientist is one of a number of folks suggesting we take a second look. Dr. Alexander Wunsch studies photobiology and feels LED lighting negatively affects our metabolism. Dr. Wunsch has a blog which presents information about light and health. Dr. Joseph Mercola conducted an interview of Dr. Wunsch which is present on a page of Dr. Mercola's discussion of the interview. This contains access to all kinds of information. With children spending a lot of time on screens this information is important for parents.