Nutritional Value of Walnuts
According to the USDA Nutrition Data, walnuts are a rich source of vitamin C, B vitamins (vitamin B6, thiamin, riboflavin, niacin, pantothenic acid, and folate), vitamin E, as well as minerals such as calcium, iron, magnesium, potassium, sodium, and zinc. 
Walnuts are 65 percent fat by weight and 15 percent protein. They are richer than most nuts in polyunsaturated fats (often considered the “good” fats) and have a relatively high amount of omega-3 fatty acid called alpha-linolenic acid (ALA). Walnuts are also particularly rich in an omega-6 fatty acid called linoleic acid.
The polyphenolic compounds and phytochemical substances found in walnuts reduce the effects of inflammation in the body. 
Walnuts help you feel full, which means that they increase satiety.  Researchers from Harvard Medical School found that people who consumed shakes containing walnuts had an increased level of fullness during the day as compared to people who had placebo shakes. This study did, however, utilize a small size, so more research is needed to confirm these results. Regardless, the rich source of protein and fiber makes walnuts a healthy snacking option, especially for vegetarians. 
This nut makes melatonin, a hormone that helps induce and regulate sleep. Melatonin is present in the bio-available form in these nuts. In a research report published in the 2005 journal Nutrition, laboratory rats that were fed walnuts showed an increase in blood melatonin concentrations as compared to rats that were fed a controlled diet without the nuts.  So, it’s good idea to add walnuts to your dinner dishes to ensure a good, restful sleep.
Walnuts are also responsible for healthy hair, as the high amounts of vitamins, minerals, healthy fats, and antioxidants strengthen hair follicles and make scalp dandruff free.  They also provide thicker, longer and stronger hair. You could also use the husk of walnuts as a natural highlighter.
The vitamin E content in walnuts helps in maintaining and protecting the skin from harmful free radicals. It also helps in preventing wrinkles and dry skin. Regular use of walnut-based products lightens the dark circles under eyes. Walnut scrubs act as a natural exfoliator and help keep the skin young and fresh.