Question

In countries where the winter is six months long and dark, children often suffer from rickets. why?

Answer 1

Rickets is caused by a vitamin D deficiency. People normally get vitamin D from the food they eat, vitamin supplements, and/or exposure to sunlight. A vitamin D deficiency is usually caused by a lack of dietary vitamin D, insufficient exposure to sunlight, and/or a medical condition that limits the body’s uptake of vitamin D such as celiac disease. 
           that is why children suffer rickets in winter coz of insufficint exposure to sunlight...

Answer 2

The defficiency of vitamin D is the main cause of rickets so the sunlight is a rich source of vitamin d due to winter it retards so therevis such problems.
Hope it helps, plz mark it brainliest...