Loose connective tissue is a category of connective tissue which includes areolar tissue, reticular tissue, and adipose tissue.Loose connective tissue is the most common type of connective tissue in vertebrates. It holds organs in place and attaches epithelial tissue to other underlying tissues.sually loose connective tissue is considered a parent category that includes the mucous connective tissue of the fetus, areolar connective tissue, reticular connective tissue, and adipose tissue.