This book focuses on presenting the current scientific evidence of biomolecular effects of selected herbs in relation to clinical outcomes and therapy for promotion of human health. Whereas many herbal medicines are made by mixing different herbs, the focus in this book is on single herb. The herbs selected cover a wide range and include flowering herbs, leaves, and leaf exudate (Aloe vera), fruits, roots and rhizomes. The use of herbs in relation to cardiovascular disease, cancer, diabetes, skin disorders, and neurodegenerative disease.