Origin: Juglans regia, the most common walnut, is native to the Asian belt stretching from the Balkans to China. The very first documented record of walnut goes back to Babylon (now Iraq) circa 2000 B.C. However, archaeological evidence speaks otherwise. During an excavation of Neolithic sites in southwest France, roasted walnut shells dating back to 8000 years were discovered. This indicates walnuts were enjoyed in Europe back then.

 It is believed that ancient Greeks began the selective breeding of walnuts. The Romans cultivated it across Europe and areas of North Africa. During the Middle Ages, walnuts were cultivated in England. From here it was taken to North America. The oldest tree food for mankind, walnuts have an interesting past. 

In Hindu mythology, walnuts are offered to God as an offering and eaten on the days of fast. In Chinese culture, carved walnuts are valued highly where they are rotated as a plaything, used as an investment and status symbol, with some fetching tens of thousands of dollars.  In the 8th century France, Charlemagne had walnut orchards planted, walnuts were used to pay French church tithes. 

In Ayurveda, walnuts are considered as Brain Food. The reason being they look like a brain and carries nutrients that enhance brain cells. Ayurveda recognizes walnuts characteristics as warm and stimulating. Thus, recommends it for Vata disorders. 

Scientifically: Walnuts are rich in monounsaturated and polyunsaturated fatty acids that decrease LDL (harmful) cholesterol and triglyceride levels. It reduces the risk of stroke and other cardiovascular diseases.  
Empowered with vitamin B6, magnesium, iron, copper and omega 3 fatty acids, walnuts ensures skin remain youthful. Walnuts copper eradicates wrinkles and enhances skin elasticity. Omega 3 fatty acids in it ensure skin is hydrated. 
Walnuts contain dietary fibers that help in weight management.  Consumption of walnuts can reduce the risk of cholecystectomy in humans. Being a good source of mineral and copper, it reduces the risk of low bone mineral density and osteoporosis. 

Magnesium present in walnuts is also efficient for bone formation. It also benefits people with epilepsy. Walnuts also help in reducing the risk of prostate cancer, and breast cancer.  High on antioxidants, walnuts combat radicals. On the irritated scalp, apply walnut oil.  
A recent study published in the Journal of Nutrition, Health and Aging highlighted that those who consumed walnuts performed better on a series of cognitive tests. Researches attributed this to the antioxidants and omega 3 fatty acids packed in this brain food. 

A 2014 study at the New York State Institute for Basic Research in Developmental Disabilities conducted on mice discovered that mice who had walnut had better memories, learning abilities, and motor coordination, and less anxiety in comparison to those mice who had a walnut-deprived diet. 

When it comes to cancer research, walnuts are the most studied nut. Various research conducted on the animal state that walnut diet slows and prevents the growth of breast and prostate cancer. 

Walnut oil is great for treating wrinkles. When applied regularly it takes care of fine lines and wrinkles fade away. Walnut oil also answers the problem of fungal infection. The Omega 3 in walnut oil takes care of hair fall and dandruff. The scary skin problem, psoriasis is also cured using walnut oil. The potassium in walnut oil works as a valuable hair tonic. 

The antioxidants, melatonin, ellagic acid, omega 3, 6 and 9, and phytonutrients present in walnut oil ensure its great for the skin.

Usage: Walnuts are often eaten raw and are used to make a pie, soup, whip, coffee, and pickles. Green Walnuts are used in making of liquor nocino. Walnuts are used in making walnut oil that is used in salad dressing and frying. It is also used in making of folk medicines. Walnut husks can be used to make durable ink for writing and drawing. Walnut shells are used for the cleaning of aviation parts because of low cost and non-abrasive qualities.
Women use walnuts as a scrub and as a mask. Walnut oil is used to massage the scalp. Adding walnut powder to henna and see nourished hair.

Below are some DIY with walnuts:

- Mix a spoon of coconut oil and honey together. Add walnut granules to it. Scrub gently. Rinse it off to get clear and radiant skin.  
- Take some crushed walnut, half a teaspoon of sugar and few drops of lemon juice. Mix them together. Apply this all over the face and massage gently. This takes away all the dead skin.
- Take some walnuts and yogurt, blend them together. Apply this over the face and leave it on for 10 minutes.  Rinse later. This helps in making skin clean an soft.
- Take a tablespoon of honey, tablespoon of coconut oil and half a cup of crushed walnuts. Mix all these ingredients together and apply on the body and gently massage in circular motions. This helps in removing dead skin and helps in getting rid of cellulite.