When it comes to your health, who you are and where you come from matter. So when you gather your family health history, include your ancestry and ethnicity. Both offer clues about your health risks.

We’ve developed tools to help you collect family history. When you ask about health conditions that run in your family, take a close look at your ancestry and ethnicity, too. Understanding both can improve your care.

Ancestry and ethnicity might seem like the same thing. In reality, they’re quite different. It’s a bit like the old nature-versus-nurture debate, although both are important:

• Ancestry refers to where your family is from, and it can offer clues about your genetics. Ancestry can be more specific than the typical “race” categories you see on forms and surveys. For example, someone who is Asian could descend from one or many ancestral groups.
• Ethnicity refers to your cultures, customs and, often, lifestyle choices.

For physicians and patients, it’s important to properly identify both ancestry and ethnicity. They’re not always physically obvious. 

Your ancestry may put you at higher risk

Some diseases occur more often among certain groups of people than in the general population. That’s why the “nature” of your ancestry matters.

For example:

• Ashkenazi Jewish people have a higher risk of carrying the BRCA gene mutation than other populations. They are also genetically predisposed to Tay-Sachs disease.
• Asians and Hispanics are genetically predisposed to thalassemia.
• Caucasians have a higher incidence of cystic fibrosis.
• African Americans have a higher risk of inheritance for sickle cell anemia and cardiovascular disease.

Don’t let this alarm you. A group’s genetic predisposition toward a disease does not mean all group members will develop it. But if you’re part of that group, your risk is higher. Your doctor may want you to go through genetic counseling and screening. You also may want to have certain tests earlier or more frequently.

Your ancestry also may affect how you respond to medications — a concept called pharmacogenetics. For example, the anticonvulsant drug carbamazepine sometimes causes severe and even fatal drug reactions in people of Asian descent. Of course, these drug reactions may still occur in people who are not Asian, and they may not occur in all people of Asian descent. But knowing makes a difference in how your doctor approaches prescriptions.

Your choices and lifestyle play a big role

This is the “nurture” side of the discussion. Ethnicity is all about your lifestyle, culture and behavior. And just like your genetics, all of these affect your health risks.

Do people in your culture eat a low-fat diet that is high in fruits and vegetables? Do they take walks as a family after dinner? Those are positive customs. On the flipside, some ethnicities have higher rates of smoking and more damaging diets.

Here’s why it matters: If you’re part of a group with a higher genetic risk, you often can reduce that risk by making better lifestyle choices. But you can only do that if you have an open, honest discussion about both ancestry and ethnicity with your care team.

Ancestry and ethnicity alone don’t determine if you will develop a disease. But you and your doctors can use both as a part of a personalized toolkit to assess your risk — and to do something about it.