You great-aunt Edna had red hair. All your cousins have brown eyes. Your father is six feet tall. Your uncle served in the military, and your brother is following in his footsteps. It usually is easy to track the physical or historical information about a family. But what about your family’s health history? Did your grandmother have breast cancer when she died at age 45? Has anyone in your family tree had heart disease?

It is important to know your family medical history because this information may hold the key to your future. Many physical traits, such as hair color, eye color and height, are inherited. Certain health conditions also can be passed on from one generation to the next. When several family members have heart disease, diabetes or some cancers, you may be at increased risk for that health problem as well.

This does not mean you will automatically inherit high blood pressure or ovarian cancer. But by compiling your family medical history, you can have a greater understanding of your health risks and take steps to reduce or prevent adverse health outcomes. If you are at risk for certain diseases, such as breast or colon cancer, your doctor may recommend more frequent screenings beginning at an earlier age. Lifestyle changes that include following a healthier diet, exercising on a regular basis or not smoking, could help lower your chance of developing heart disease or other common illnesses.

The best way to start a family health history is to talk to relatives. Older family members may not want to share this information or they may not know their medical history. But whatever you can discover may be helpful. Start with information about yourself and add medical background on your parents, siblings and children. Then start going back one generation at a time to include nieces, nephews, aunts, uncles, grandparents and cousins. 

Pertinent information would include date of birth, age, age at death, cause of death and any known medical problems, such as cancer, heart disease, diabetes, asthma, mental illness, high blood pressure, stroke, kidney disease and alcoholism. Also note related conditions that include breast and ovarian cancer, colon and endometrial cancer, and thyroid cancer and colon polyps. When possible, record the age at onset of the condition. Other medical problems that should be included are birth defects, such as spina bifida, cleft lip or heart defects, learning problems or mental retardation, vision or hearing loss at a young age, sudden death in someone who was otherwise healthy, and multiple miscarriages or stillbirths. If you know where your family originated, such as Europe, Africa or South America, record that as well. Some genetic health problems occur more frequently in certain ethnic groups.

A family health history is a living document that should be reviewed and updated every couple of years. To get started, you can create a free, downloadable version of My Family Health Portrait developed by the U.S. Department of Health and Human Services.