Doctors say while it's important for people to establish fitness goals in the new year, there are other additional health goals people should work on.

The first step people can do to improve their overall health is to make a doctor's appointment to get a handle on key health numbers – including blood pressure and blood sugar.

Another key reading is blood oxygen level, which is crucial to vital organ function. For this, they use a pulse oximeter. Doctors say it gauges if blood is carrying enough oxygen to the lungs, heart and brain.

Officials have said that pulse oximeters do not provide a reliable reading on everyone. Studies have found that the devices measure higher levels for people with dark skin. In response, the Food and Drug Administration has proposed guidance to make the devices more reliable.

This week, the FDA announced it would recommend manufacturers of pulse oximeters do conduct specific clinical testing and labeling of the devices.

Other key health numbers to track include one's body mass index, cholesterol and resting heart rate.