Natural Alternatives International, Inc. (NAI) is an American company based in Carlsbad, California which manufactures nutritional supplements such as Juice Plus.

NAI's manufacturing facilities are located in Vista, California, Switzerland and Japan.

[2] NAI manufactures products sold by other companies such as National Safety Associates, Mannatech,[3] NuSkin Enterprises, Jenny Craig, and Dr. Reginald Cherry.

NAI previously held a multimillion-dollar contract with the U.S. Olympic Committee, which expired in March 1997.

[7] During the fiscal year ended June 30, 2006, National Safety Associates accounted for approximately 38% of NAI's net sales.