Health Effects of Coconut Oil—A Narrative Review of Current Evidence

Coconut oil is a mainstream edible oil that is extracted from the kernel of mature coconuts harvested from the coconut palm. The two main types of coconut oil-copra oil and virgin coconut oil-have similar fatty acid profiles; however the latter contains higher amounts of some nutrients (e.g., vitamin E) and dietary bioactive compounds (e.g., polyphenols). There is increasing popularity for coconut oil products due to perceived health effects of certain medium-chain fatty acids; however, lauric acid (C12:0), the primary fatty acid found in coconut oil, has been suggested to behave as both a medium- and long-chain fatty acid from a metabolic standpoint. Furthermore, research on pure medium-chain fatty acids cannot be directly applied to coconut oil products since it encompasses a large profile of various fatty acids. This narrative review seeks to summarize the current peer-reviewed literature and mechanisms surrounding the health effects of coconut oil products. Limited but consistent evidence supports the topical use for prevention and treatment of atopic dermatitis, as well as in "oil pulling" for prevention of dental caries. Coconut oil products may also be useful in preventing hair damage due to protein loss during grooming processes and ultraviolet (UV) exposure; however, more studies are needed to confirm this effect. Limited evidence does not support use for prevention or treatment of Alzheimer's disease, bone loss, or glycemic control. Evidence on weight loss and cardiovascular disease warrants larger clinical intervention studies. Refined, bleached, and deodorized copra oil seems to have less of an impact on total and low-density lipoprotein (LDL) cholesterol as compared to butter fat, but not cis unsaturated vegetable oils. In many instances, human clinical and observational studies are needed to confirm many claims on coconut oil products, which are largely based on animal and/or in vitro studies or studies of purified medium-chain fatty acids.