Unfortunately, chickens raised either for meat (broilers) or for eggs (layers) suffer terribly.
Some people switch from eating cows to eating chickens because they think that will make them healthier. However, a recent study has shown that there are no benefits of choosing "white meat" over "red meat". Unfortunately, this misconception leads to a lot more animal suffering, because it takes more than 200 chickens to produce the same amount of meat as one cow, and chickens live and die under conditions that are terrible even in relation to the horrible conditions that all food animals endure. Here is more information on what chickens who are raised for meat have to endure.
Additionally, eating chickens is associated with health hazards such as food poisoning and exposure to cancer-causing viruses, and chicken meat contains plenty of saturated fat and cholesterol. Here are some details from NutritionFacts.org on the health hazards of eating chickens.
Learn more about the impact on animal suffering of just stopping eating chickens here.