How to collect your family health history
A parent or sibling with colon, breast or prostate cancer can move some screenings earlier, but only if you know who had what, and at what age. Here is who to ask, what to write down, and the free tools that help.
Why it matters
Families share genes and often environments and habits. A family health history can show a higher-than-usual chance of heart disease, high blood pressure, stroke, certain cancers and type 2 diabetes. For people at increased risk of certain cancers, doctors may recommend screening such as mammography or colonoscopy more often and from an earlier age. (MedlinePlus)
Who to ask
- Three generations. Children, brothers and sisters, parents, aunts and uncles, nieces and nephews, grandparents and cousins. (MedlinePlus)
- Close relatives first. Parents, brothers, sisters and children (first-degree relatives) matter most for the screening rules below, but 2 or more relatives with colorectal cancer, or one diagnosed younger than usual, also matters. (ACS, 2024)
- Talk, then check records. Ask relatives what health problems they had and when. A family gathering can be a good time. Medical records, obituaries and death certificates can fill gaps. (MedlinePlus)
What to write down
For each relative, note three things: who (and which side of the family), what condition, and their age when it was found. These are the details screening rules ask about:
| If a relative had | Write down | Why it matters |
|---|---|---|
| Colorectal cancer or advanced polyps | Which relative, and their age at diagnosis | A first-degree relative diagnosed before 60 means colonoscopy every 5 years from 40, or 10 years before their age at diagnosis (USMSTF, 2017) |
| Prostate cancer | Father or brother, age at diagnosis, how many | Diagnosed before 65: talk about PSA at 45; more than one: at 40 (ACS, 2023) |
| Breast, ovarian, tubal or peritoneal cancer | Which relative, which cancer, family ancestry | Triggers a brief risk check and possible genetic counseling (USPSTF, 2019) |
| Type 2 diabetes | Which relative | Clinicians should consider screening earlier with a family history of diabetes (USPSTF, 2021) |
Keep it up to date and share it with your doctor regularly. (MedlinePlus) Then see family history: when screening starts earlier for the full rules.
Free tools
- My Family Health Portrait. Launched by the U.S. Surgeon General's Family History Initiative. You enter your family's health history, print it to share with family or your doctor, and save it to a file you reopen later. (NHGRI) (My Family Health Portrait) Its old CDC address now says the hosting site is no longer available as of April 13, 2026; NHGRI links the working copy. (CDC PHGKB)
- Families SHARE (NHGRI). Printable risk worksheets for colorectal cancer, breast cancer, prostate cancer, type 2 diabetes and heart disease, plus a workbook in four languages. (NHGRI, 2025)
- Paper works too. The three columns in the table above are enough to bring to a visit.
This site does not collect or store family history. Our screening planner follows USPSTF advice for people at average risk (Method); if your family history raises your risk, take your notes to your doctor.
Questions people ask
Which relatives should I include?
MedlinePlus says a complete record covers three generations: children, brothers and sisters, parents, aunts and uncles, nieces and nephews, grandparents and cousins. (MedlinePlus)
Why does the age at diagnosis matter?
Several screening rules depend on it. For example, the US Multi-Society Task Force advises earlier colonoscopy when a parent, brother, sister or child had colorectal cancer before 60, and the American Cancer Society starts the prostate talk at 45 when a father or brother was diagnosed before 65. (USMSTF, 2017) (ACS, 2023)
What if I cannot ask my relatives?
MedlinePlus notes that medical records and other documents, such as obituaries and death certificates, can help complete a family health history. (MedlinePlus)
Is My Family Health Portrait still available?
The old CDC address now shows a notice that the hosting site is no longer available as of April 13, 2026. NHGRI links a working copy, which lets you enter your history, print it and save it to a file you open again later. (CDC PHGKB) (NHGRI) (My Family Health Portrait)
Does no family history mean I am safe?
No. MedlinePlus says a person with no family history of a disorder may still be at risk, and having relatives with a condition does not mean you will definitely get it. (MedlinePlus)