The Earth's Crust is like the skin of an apple. It is very thin in comparison to the other three layers. The crust is only about 3-5 miles (8 kilometers) thick under the oceans(oceanic crust) and about 25 miles (32 kilometers) thick under the continents (continental crust).
The problem behind your itchy skin might be insufficient vitamin intake. There are a number of vitamins that promote the hydration and healthiness of your skin. A shortage in these could trigger itchiness, dry skin and other skin conditions. Alternatively, an overdose of such vitamins might also lead to itchy skin.
According to the Ronald Marks, author of Practical Problems in Dermatology, the most common cause of itchy scalp is simple dry skin, and poor dietary habits are a risk factor that can make you more susceptible to dry skin, itchy scalp and dandruff.dding foods rich in vitamin A to your diet might help improve skin health, alleviating scalp itch. Foods that are good sources of vitamin A include eggs, butter, dairy products, sweet potatoes, squash, carrots, cantaloupe and papaya.