Research published in the American Journal of Clinical Nutrition shows that Vitamin D deficiency is incriminating… factor for breast cancer. The survey carried out by a team of scientists from various organizations, and concerned the study of data from cases of breast cancer in Saudi Arabia, showed that the incidence of breast cancer was 6 times more common in women who had Vitamin D deficiency. 
The researchers studied data from 120 cases of breast cancer and a corresponding control unit. It was found that women who had the lowest Vitamin D levels less than 25 nmol/L (10 ng/ml), were at 6 times higher risk of aggressive breast cancer, compared with women who had the highest levels of Vitamin D, that is, higher than 50 nmol/L (20 ng/ml). Paradoxically, women in Saudi Arabia if residing in an area with intense sunshine, it seems that they have very low Vitamin D levels. This is due to the modern way of life conducive to remaining indoors, in dark skin color, in the traditional imperative way of clothing as well as the fact that the food is not fortified with Vitamin D as in other countries, such as Canada and The us.E.A.
Vitamin D is of great value to the organization. It is known that it protects the bones from fractures and osteoporosis, but has a key role in many other diseases such as tuberculosis, psoriasis, multiple sclerosis, inflammatory bowel disease, type 1 diabetes, high blood pressure, myopathy, breast cancer and other types of cancer. 
The main source of Vitamin D is the sun, as it is produced by the body when exposed to sunlight. Vitamin D is also contained in some foods – the best sources are fatty fish, such as salmon, mackerel, sardines, and cod liver oil. There is also in small quantities in liver, eggs and fortified foods such as fortified milk, margarine, cereals.
In our country the main source of Vitamin D is sunlight. Most people get enough Vitamin D during the daily activity. To get enough sunlight your body to produce Vitamin D, expose your palms to the face and hands (or equivalent area of skin) to sunlight for about 5-15 minutes 4-6 times a week. Older people and people with a more brunette complexion need more exposure to sunlight – about 15 minutes 5-6 times a week.
The long periods of sunshine in our country and even in the winter months favor the adequacy of Vitamin D. However, in cases where the body does not synthesize sufficient Vitamin D is necessary to take dietary measures to meet individual needs. These may include fortified Vitamin D foods and supplements, especially for high-risk groups for deficiency in vitamin.
Source
An increased risk of breast cancer in women with a deficiency-lack of Vitamin D
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