Ahmet ÜNLÜ, Mustafa ÖZDOĞAN, Oben DUMAN, İrfan ÖĞRETMEN, Önder KIRCA

D Vitamini ve Kanserden Korunma

D vitamini, esas olarak kemik sağlığı için gerekli olmakla birlikte vücutta birçok olayda rol oynayan, yağda çözünen vitaminler grubundan bir bileşiktir. Güneşten gelen ultraviyole ışınlarına maruziyet sonucu vücutta endojen olarak üretilebilen D vitamini, aynı zamanda bazı besinlerde doğal olarak bulunmakta veya D vitamini takviyelerinden elde edilebilmektedir. D vitamini uzun yıllardır bilinen görevlerinin yanı sıra, son yıllarda kanser, diyabet, kalp hastalıkları gibi bazı hastalıklardan korunmadaki etkisiyle de sıkça gündeme gelmektedir. Yapılan bazı araştırmalarda; güneşe maruziyetin az olduğu bölgelerde bazı kanser türlerinin daha sık görüldüğünün gözlenmesi, D vitamininin kanserden korunmada etkili olduğu düşüncesini doğurmuştur. Yapılan laboratuvar çalışmalarında, D vitamininin kanserden korunmada etkili olabileceğine dair güçlü kanıtlar elde edilse de; randomize klinik çalışmaların sonuçları çelişkilidir. D vitamini; hangi dozlarda yararlı, hangi dozlarda zararlı, hangi kanser türlerinde etkili, net olarak bilinmemektedir. Bu noktada, iyi tasarlanmış kapsamlı çalışmalara ihtiyaç vardır. Yapılacak çalışmalar için anahtar; bazı kanser türlerinin riskini azaltan, ancak diğerlerinin riskini artırmayan ideal D vitamini miktarının belirlenmesi olacaktır

Anahtar Kelimeler:

D vitamini, Kanser, Kanserden korunma, Kemoprevensiyon

Vitamin D and Cancer Prevention

Vitamin D is essential for bone health, and is a compound in the group of fat-soluble vitamins, which plays a role in many events in the body. Vitamin D can be produced as an endogenous substance in the body as a result of exposure to ultraviolet radiation coming from the sun and is also available in certain natural foods or can be obtained from vitamin D supplements. Besides its duties that have been known for years, Vitamin D has been of interest in recent years due to its role in protection against some diseases such as cancer, diabetes, and heart disease. The idea that vitamin D is effective in protection against cancer was born as a result of the fact that certain types of cancer were observed to be more commonly encountered in regions where sun exposure was low in some studies. Although strong evidence has been obtained that vitamin D is likely to be effective in protection from cancer, the results of randomized clinical studies are inconsistent. Vitamin Dʼs beneficial and harmful doses, and the types of cancer on which it is effective, are not clearly known. At this point, well-designed comprehensive studies are needed. The key for the further studies will be the determination of the ideal amount of vitamin D that will reduce the risk of some cancers but will not increase the risk of some others

Keywords:

Vitamin D, Cancer, Cancer prevention, Chemoprevention,

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