Walnut is very high in linoleic acid and antioxidants. It is used to repair damaged or dry skin and to prevent wrinkles. It is best used as less than 15% of a carrier oil composite blend. Walnut oil contains an anti-oxidant, ellagic acid, which research—still in early stages—is reporting and showing an ability to detoxify several compounds that have been linked to the development of certain types of cancers. High anti-oxidant concentrations have been shown to help fight the signs of aging as well.
Walnut oil, when taken internally (why not just eat walnuts?) creates an increase in the strength and resilience of blood vessels and improves circulation. It accomplishes this by preserving the function of the endothelial cells which line the walls of the blood vessels. This reduces hardening of the artery walls. Hardening of the arteries is considered a major contributor to high blood pressure and heart disease.
Walnut oil has a short shelf life and must be kept refrigerated and stored with a tight lid. Walnut oil is certainly not recommended for persons with a nut allergy of any sort without extreme care and caution.