United Natural Foods' Western Region has distribution centers in Rocklin, CA, Fontana, CA, Auburn, WA, and Aurora, CO. UNFI Western Region Distribution services customers in the Western and Central United States with an extensive selection of natural and organic products in all categories, including grocery, dairy, frozen, beverages, bulk, health and beauty, nutritional supplements, pet care and general merchandise. UNFI Western Region Distribution is made up of what was formerly Mountain Peoples Warehouse (MPW) and Rainbow Natural Foods.

As the leading natural foods distributor in the Western and Central United States, UNFI offers the widest selection of products at competitive prices, with retail support services including merchandising, category management, promotional tools, sales flyers, and new store support.

With our large fleet of refrigerated trucks, we distribute not only to all of the metropolitan markets, but to many rural markets as well. Mountain Peoples Warehouse proudly claimed to "Boldly go where no distributor has gone before."

Founded in 1976 in Northern California, MPW originally began selling only organic produce, but soon expanded its product line to include perishables, bulk and groceries. After a series of acquisitions, Whole Foods Express in 1991, NutraSource in 1995, and Shojin Natural Foods in 1997, MPW became the largest full line natural foods distributor in the West. In 1996, MPW merged with Cornucopia Natural Foods to form United Natural Foods.

Rainbow Natural Foods began in the 1970s as a retail food co-operative, selling natural food products and organic produce in Denver. Rainbow was a pioneer in the natural foods industry, and slowly developed a distribution business by selling products to other retailers.

During the '80s, Rainbow continued to grow, adding new retail locations and continuing to expand its distribution business. A decision was made to separate the retail from the wholesale, and the retail stores were sold. The wholesale business retained the Rainbow name.

The '90s brought continued growth as more people became aware of natural and organic products. Rainbow was purchased by Cornucopia Natural Foods (one of the founding companies of UNFI) and eventually became the Central Region headquarters for United Natural Foods. Today they are part of UNFI's Western Region, serving the central U.S.