There are many different effects of steroids. They range from positive effects, to health/life threatening to simply undesirable.

One of the biggest effects of steroids is the ability for steroids to build up lean body mass and strength in its user. These effects of steroids are great for athletes and body builders who want to increase their performance as well as for patients of certain medical conditions who need a boost. This includes treatment of chronic wasting and a boost in growth for children. These specific effects of steroids are possible because of their ability to promote cell growth and division of various body tissues including muscle and bone.

Other effects of steroids include the inhibition of natural hormone production in the body. This generally refers to testosterone production because the human body is programmed to keep hormone levels balanced. It's important to be aware of this because, while the body will start producing natural hormones once there is no longer synthetic hormones in the system (again, to keep the balance) it may take some time before the levels are back to normal. This lull in the levels can cause a reversal of the effects of the steroids in terms of building muscle mass. This effect of steroids can be managed by taking certain drugs such as anti-estrogens.

Gynocomastia is also one of the effects of steroids. This is when males who use anabolic steroids develop breast tissue as a result of the increase of estrogen in the body. Related effects of steroids are virilization in females which is the appearance of masculine characteristics due to the increased levels of testosterone in the female body. This includes a deepening voice and increase in body hair and the appearance of male pattern baldness.

Some effects of steroids can be life-threatening. These effects of steroids include liver and kidney damage from the digestion of the steroid, elevated total cholesterol levels, increased blood pressure and a higher chance of developing certain cancers