Cataracts develop when the natural lens inside the eye turns yellow and hard. Doctors classify the types of cataracts depending on the location and growth pattern of the cataract. A nuclear sclerosis cataract, also referred to as a nuclear cataract, grows in the central part of the natural lens. Nuclear cataracts commonly occur with age, but they may appear early. Knowing some of the causes and risk factors may help a person understand the condition.

Some infants have nuclear cataracts at birth, a condition called congenital cataracts, states the Edward S. Harkness Eye Institute at Columbia University. The cataract usually covers a small central area of the natural lens but may not drastically affect vision. A parent or pediatrician will often notice a white appearance to the center of the pupil, an indication of a congenital cataract. Doctors will monitor the cataract for growth, and as the child ages, the doctor will ensure that the child does not have vision loss due to the cataract. In some cases, congenital cataracts may accompany other diseases or conditions, such as congenital rubella, Down syndrome or Lowe syndrome, explains MedlinePlus.

Injury to the eye may cause damage to the tissues of the natural lens, resulting in the early development of a cataract, according to MayoClinic.com. Wearing protective eyewear during sports such as racquetball may help prevent injury to the eye, which will reduce the likelihood of cataract development.

People with diabetes have an increased risk of developing nuclear cataracts, reports The Eye Digest, an online publication of the University of Illinois Eye & Ear Infirmary. For overall health, diabetics should monitor and control blood glucose levels to decrease the risk of complications of the disease, and this may also reduce the risk of developing an early cataract.

Doctors often prescribe steroid medications to treat certain conditions, and some eye conditions, such as extensive eye infections, may require steroid eye drops to help with healing. Long-term use of steroids may increase the risk for developing a cataract.

Certain lifestyle factors may contribute to the growth of cataracts. For example, cigarette smokers and people who use steroids have an increased risk. In smokers, the various components in the cigarette may damage the protein and cells that make up the natural lens, explains The Eye Digest. Smoking cessation may not reduce the risks of cataract immediately, but stopping will have many positive effects on the body in general.