Grapeseed oil is a byproduct of winemaking. After wine is made by pressing grapes, grape seeds are left behind. Grapeseed oil is extracted from these leftover grape seeds. Grapeseed oil is used as a natural beauty product. Itâ??s also marketed as a healthy alternative to vegetable oil. Grapeseed oil is a good source of vitamin E, even more so than olive oil. Vitamin E is a vitamin that works as a fat-soluble antioxidant, which helps protect your cells from damaging free radicals that have been associated with cancer, heart disease, and other chronic illnesses. Vitamin E also supports your immune system. Research shows it may slow the progression of dementia, but more study is needed. Grapeseed oil may improve the condition of your hair and scalp.