In the 18th century, Franciscan monks planted walnuts in California, where the mild climate and fertile soil provided ideal growing conditions. California now provides 99% of the United States' and 67% of the world's supply of walnuts. The walnut's botanical name, Juglans regia, comes from the Romans and means "the royal acorn of Jupiter." The Afghani word for walnut is charmarghz or "four brains" because of the unique shape of the walnut kernel. Walnut trees can live for 250 years.
- high levels of amino acid L-arginine help control hypertension
- ellagic acid strenghtens the immune system and helps prevent breast and prostate cancer
- omega-3 fatty acids protect agains rheumatoid arthritis, lupus, eczema, and psoriasis
- with 16 polyphenols, walnuts have the highest antioxidant content of the tree nuts