You get your checkups and and live on kale—great! But if you don’t know why Grandpa was in the hospital last year or what your mom takes those meds for, you’re missing out on a vital part of staying healthy. Your family health history—the conditions that relatives have, have had, or died of—can provide hints about what to expect regarding your own health. Not only do you and your close relatives share many genes, which can play a role in your risk of diseases like diabetes and cancer, but families also tend to have similar lifestyle habits, from daily walks to gut-busting Sunday dinners, that affect health.
With the right knowledge, you may even be able to sidestep your genetic destiny. "For example, you can make lifestyle changes to reduce your risk of cancer, and get screenings to increase the likelihood of catching a cancer early," says Deborah Lindner, MD, chief medical officer for Bright Pink, a nonprofit that focuses on the prevention and early detection of breast and ovarian cancer.
Gathering medical details (including info on mental health and pregnancy complications) on all your relatives is a huge project, and you won’t complete the whole tree in one fell swoop. But you’ll be doing a service not just to yourself but to your entire clan. Let that be your nudge to say at the next family reunion, "Pass the potato salad—and, oh, what was up with Uncle Pete’s liver?"
Your goal: Collect info on health conditions (with age of diagnosis), ethnic background, and age and cause of death for three generations of blood relatives. At the minimum, get info on first-degree relatives (these are the light blue people in the family tree above).
To get started, ask grandma
The family matriarch (your mom? your great-aunt?) will often have a lot of details that can get you started (maybe she knows that several relatives have had heart problems) or can fill in the gaps about relatives who have passed away, says James O’Leary, chief innovation officer for Genetic Alliance, a health advocacy organization. If truly no one knows what a particular relative died of, try looking up his or her death certificate or obituary.
Next, get it all down
The My Family Health Portrait tool from the U.S. Department of Health & Human Services helps you create a family health history tree and save it to your computer (so you can change it as your family circumstances do), share it with other family members, or print to show your doctor.
Keep track of seemingly unconnected diseases that can go hand in hand
Alzheimer’s + heart disease: A gene called APOE plays a key role in forming lipoproteins, which carry cholesterol and other fats through your bloodstream. Having a specific variant of this gene has been associated with fatty deposits in the arteries (increasing the risk of heart attack) and protein clumps in the brain, which may be linked to dementia.
Breast cancer + pancreatic cancer: Mutations in the BRCA1 and BRCA2 genes not only make you more prone to breast and ovarian cancer but are also connected to an increased risk of pancreatic cancer, the third leading cause of cancer-related death in the United States.
Breast cancer + prostate cancer: For postmenopausal women who have a first-degree relative diagnosed with prostate cancer, the risk of breast cancer is 14 percent higher than average, suggests a 2015 study. When both breast and prostate cancers run in the family, the risk is 78 percent higher than average.
Autoimmune diseases (like type 1 diabetes + lupus): Autoimmune conditions tend to run in families. Researchers posit that this may be due to both environmental factors and a genetic link that predisposes family members to various types of autoimmune diseases.
What if I was adopted?
It’s still possible to pull together a good amount of helpful info. Start with yourself: That’s the first step in informing future generations. If you have biological children, you can also look to them; you may be susceptible to certain conditions they have. Want to dig deeper? You might be able to get health info about your biological parents through the agency that handled your adoption (laws vary by state). Your state’s health and social service agency can guide you through the process of accessing medical records.