Omega 3 oils contain omega-3 fatty acids, which are necessary for brain function and normal growth and development, according to the University of Maryland Medical Center. They help lower cholesterol and high blood pressure, and protect against heart disease, diabetes, rheumatoid arthritis, systemic lupus, osteoporosis, Alzheimer's disease and psychiatric disorders.
Omega-3 fatty acids are necessary for health and must be supplied by the diet since they cannot be made by the body, according to WebMD. They are found in the oils of certain fish, nuts and seeds, and it is best to get omega-3 fatty acids from foods rather than supplements. WebMD recommends eating fish two to three times per week.