Canning does not reduce the nutritional value of beans but canned beans do cost considerably more than dried varieties. For example, 425 g of canned lima beans will give 250 g drained weight only, while 100 g of dried beans bulks up to the same weight after soaking and cooking.
Dried beans work out at less than a third of the price, but lima and some other beans require long cooking. The time and energy saved by using these beans canned may well justify the additional cost.
Whether you choose canned or dried, beans are a good source of protein, fiber and complex carbohydrates. They are low in fat and contain minerals as well as nearly all the vitamins we need.