What changes in your 40s?
Two cancer screens start this decade — mammography at 40 and colorectal at 45 — and the heart question arrives at the same time. From 40 the USPSTF wants a 10-year risk estimate, and when that estimate lands between 3% and 10% a calcium-score CT from 45 is the tie-breaker the 2026 ACC/AHA guideline recommends. Blood pressure moves to a yearly reading.
The 40s are also when perimenopause begins for many women, which changes bone and heart risk but does not, on its own, add a screening test: DEXA waits until 65 unless you are postmenopausal with a risk factor. What is still not recommended is as important as what is: thyroid ultrasound, tumor markers and whole-body MRI all carry a D or an I.
Which screenings are recommended for women aged 40–49?
These carry a guideline grade of A or B, or are the only guideline there is. The age next to a test is where the guideline starts or stops it, not an average.
Blood pressure check
- When
- Every year from 40, or earlier if you are at higher risk. At 18–39, every 3–5 years if your last reading was normal and you are not at higher risk.
- Why it is worth doing
- High blood pressure has no symptoms. Treating it lowers hospital admissions for heart attack, heart failure and stroke; in the one trial of screening itself, admissions fell by 9% (USPSTF 2021, grade A for all adults 18 and over).
- What the result lets you do
-
- Normal: Repeat at the interval for your age.
- Borderline: A single high reading is not a diagnosis. The USPSTF asks for out-of-office readings — a home cuff or a 24-hour monitor — before treatment starts.
- Abnormal: Confirmed high readings mean a treatment plan with your doctor; lifestyle change comes first for mild cases.
- Notes
-
- Higher risk means previous high-normal readings, overweight or obesity, or being a Black adult.
- Read more
- Blood pressure check: what it finds, who it is for, and what to expect
Lipid panel (total, LDL and HDL cholesterol, triglycerides)
- When
- At least every 5 years from 19 (ACC/AHA 2026).
- Why it is worth doing
- The lipid panel is the input to every heart-risk decision you will make for the next 50 years. The 2026 ACC/AHA guideline recommends it from 19 and at least every 5 years, and the statin trials (next row) are where the benefit shows up.
- What the result lets you do
-
- Normal: Repeat within 5 years.
- Borderline: Your 10-year risk estimate decides, not the LDL number alone; a calcium score settles uncertain cases.
- Abnormal: An LDL of 190 mg/dL or more means a statin regardless of the risk score, and testing of first-degree relatives for familial hypercholesterolemia.
- Notes
-
- Fasting is no longer required for a first panel in most guidelines; the clinic's instructions for your booking decide.
- Read more
- Lipid panel (total, LDL and HDL cholesterol, triglycerides): what it finds, who it is for, and what to expect
Lipoprotein(a) blood test
- When
- Once in a lifetime.
- Why it is worth doing
- Lp(a) is set by your genes and does not move with diet or exercise. The 2026 ACC/AHA guideline recommends measuring it at least once in every adult, because a high level is a risk enhancer that lowers your LDL target and brings forward a calcium score.
- What the result lets you do
-
- Normal: Done; no repeat needed.
- Abnormal: A high level means a lower LDL target and earlier calcium scoring, and first-degree relatives should be tested.
- Read more
- Lipoprotein(a) blood test: what it finds, who it is for, and what to expect
10-year heart-risk estimate from your lipid panel — from 40
- When
- Whenever the lipid panel is repeated, run the 10-year risk estimate.
- Why it is worth doing
- At 40–75 with at least one risk factor and a 10-year risk of 10% or more, a statin cuts heart attacks by about a third (relative risk 0.67 across 12 trials of 76,498 people) and all-cause death by 8% (USPSTF 2022, grade B).
- What the result lets you do
-
- Normal: Under 7.5%: no statin; repeat the panel at the usual interval.
- Borderline: 7.5% to under 10%: an individual decision with your doctor (grade C); a calcium-score CT can settle it either way.
- Abnormal: 10% or more with a risk factor: a statin discussion is the guideline answer. The result is the start of treatment, not the end of testing.
- Notes
-
- Risk factors: dyslipidemia, diabetes, hypertension or smoking.
- Over 75 the evidence is insufficient (grade I).
- Read more
- 10-year heart-risk estimate from your lipid panel: what it finds, who it is for, and what to expect
HbA1c and fasting glucose
- When
- Every 3 years if normal.
- Why it is worth doing
- Prediabetes is reversible: in the trials a lifestyle program cut progression to diabetes by about a fifth (pooled relative risk 0.78), and the Diabetes Prevention Program by 58%. USPSTF grade B at 35–70 with overweight or obesity (BMI 25 or more, or 23 or more for Asian Americans); the ADA tests everyone from 35.
- What the result lets you do
-
- Normal: HbA1c under 5.7%: repeat in 3 years.
- Borderline: 5.7–6.4% is prediabetes: a structured lifestyle program, and a retest every year.
- Abnormal: 6.5% or more: one value is not a diagnosis. A second abnormal test confirms it, then treatment with your doctor.
- Notes
-
- HbA1c can mislead with anemia or a hemoglobin variant.
- Read more
- HbA1c and fasting glucose: what it finds, who it is for, and what to expect
Colorectal cancer screening (colonoscopy or FIT stool test) — from 45
- When
- A colonoscopy every 10 years, or a FIT stool test every year. At 76–85 it is an individual decision.
- Why it is worth doing
- Screening from 45 averts an estimated 24–28 colorectal-cancer deaths per 1,000 people screened, because a colonoscopy removes precancerous polyps before they turn into cancer (USPSTF 2021: grade A at 50–75, B at 45–49).
- What the result lets you do
-
- Normal: Next colonoscopy in 10 years; FIT again next year.
- Borderline: Small polyps removed: the pathology report sets the next interval — 1–2 small adenomas, 7–10 years; 3–4, 3–5 years; 5–10, 3 years; more than 10, 1 year (US Multi-Society Task Force 2020).
- Abnormal: A positive FIT needs a colonoscopy. An adenoma of 10 mm or more, villous histology or high-grade dysplasia means a 3-year repeat and a specialist plan.
- Notes
-
- Earlier and more often with a first-degree relative diagnosed before 60.
- Taiwan funds a FIT at 45–74 every 2 years.
- Read more
- Colorectal cancer screening (colonoscopy or FIT stool test): what it finds, who it is for, and what to expect
Mammography — from 40
- When
- Every 2 years (USPSTF). The American Cancer Society offers yearly screening at 45–54.
- Why it is worth doing
- Biennial mammography at 40–74 lowers breast-cancer deaths by about 15% in relative terms; starting at 40 rather than 50 averts 1.3 more deaths per 1,000 women (USPSTF 2024, grade B).
- What the result lets you do
-
- Normal: BI-RADS 1 or 2: next mammogram in 2 years.
- Borderline: BI-RADS 0 or 3: extra views or an ultrasound, or a 6-month check. Most of these are not cancer.
- Abnormal: BI-RADS 4 or 5: a biopsy decides. The breast-imaging page explains the BI-RADS ladder.
- Notes
-
- Dense breasts: the evidence for an extra ultrasound or MRI is insufficient (grade I); about half of women over 40 have dense breasts.
- At 75 and over the evidence is insufficient (grade I).
- Read more
- Mammography: what it finds, who it is for, and what to expect
Cervical screening (Pap smear; HPV test where available)
- When
- At 21–29, a Pap every 3 years. At 30–65, a Pap every 3 years, an HPV test every 5 years, or both every 5 years. Screening stops at 65 when the earlier record was adequate and negative.
- Why it is worth doing
- Regular cervical screening finds precancerous change years before cancer. In the USPSTF model it cuts cervical-cancer deaths from 8.34 to 0.76 per 1,000 women (2018, grade A at 21–65).
- What the result lets you do
-
- Normal: Next test at your interval.
- Borderline: ASC-US or a low-grade change: an HPV test or a repeat in 12 months, by ASCCP rules.
- Abnormal: A high-grade change or HPV 16/18: colposcopy with biopsy.
- Notes
-
- No screening after a hysterectomy that removed the cervix for benign reasons.
- A December 2024 USPSTF draft would make the HPV test every 5 years the preferred option at 30–65 and allow self-collection; it is not final.
- New Dawn Health offers a Pap smear; the HPV test is not in our catalog.
- Read more
- Cervical screening (Pap smear; HPV test where available): what it finds, who it is for, and what to expect
Hepatitis B blood test (three-part panel)
- When
- Once in a lifetime; repeat only with ongoing risk.
- Why it is worth doing
- The CDC recommends that every adult be tested once with a three-part panel (HBsAg, anti-HBs, anti-HBc). Antiviral treatment of chronic infection cuts the risk of death from liver disease by about 85% in the USPSTF evidence (relative risk 0.15). People born where hepatitis B is common, including most of Asia, are the group most often affected.
- What the result lets you do
-
- Normal: Immune or never exposed: done; a vaccine if you are not immune.
- Borderline: A past, resolved infection: no treatment; tell your doctor before any immune-suppressing medicine.
- Abnormal: HBsAg positive: a liver specialist, and liver-cancer surveillance with ultrasound plus AFP about every 6 months for carriers in the AASLD groups — men over 40 and women over 50 from a country where hepatitis B is endemic, anyone with a family history of liver cancer, and everyone with cirrhosis.
- Notes
-
- The USPSTF grade B covers adults at increased risk; the CDC 2023 recommendation is universal.
- Read more
- Hepatitis B blood test (three-part panel): what it finds, who it is for, and what to expect
Hepatitis C antibody test
- When
- Once; repeat with ongoing risk.
- Why it is worth doing
- A one-time antibody test at 18–79 finds an infection that modern antivirals cure in 95–99% of people in 8–12 weeks (USPSTF 2020, grade B).
- What the result lets you do
-
- Normal: Done.
- Borderline: Antibody positive: an RNA test tells a current infection from a past one.
- Abnormal: RNA positive: treatment with direct-acting antivirals.
- Read more
- Hepatitis C antibody test: what it finds, who it is for, and what to expect
HIV test
- When
- At least once; repeat with ongoing risk.
- Why it is worth doing
- The USPSTF grades HIV screening A at 15–65, because treatment started early keeps the virus undetectable and stops transmission.
- What the result lets you do
-
- Normal: Done, unless risk continues.
- Abnormal: Confirmatory testing and a same-week referral.
- Notes
-
- Not part of our standard screening panels; ask your coordinator, or test at home before you travel.
- A USPSTF update is in progress; no draft has been posted.
Comprehensive eye exam
- When
- With no risk factors (AAO 2025): under 40, every 5–10 years; 40–54, every 2–4 years; 55–64, every 1–3 years; 65 and over, every 1–2 years. Get a screening by 40.
- Why it is worth doing
- The USPSTF finds the evidence insufficient for glaucoma screening at 40 and over (2022, grade I). The American Academy of Ophthalmology still sets an interval for every age and asks for a screening by 40, because glaucoma and early retinal disease have no symptoms until vision is lost.
- What the result lets you do
-
- Normal: Repeat at the AAO interval for your age.
- Abnormal: Pressure, visual-field or retinal findings are followed by an ophthalmologist; diabetes and high blood pressure shorten the interval.
- Notes
-
- Diabetes, a family history of glaucoma, or African or Hispanic ancestry over 40 mean shorter intervals.
- Read more
- Comprehensive eye exam: what it finds, who it is for, and what to expect
Dental check-up and cleaning
- When
- The interval is set by your dentist — once or twice a year for some people, more often for others (ADA).
- Why it is worth doing
- Gum disease and decay are silent until late, and gum disease tracks with diabetes and heart disease; a check and cleaning catch both early. The American Dental Association does not set a universal 6-month rule.
- What the result lets you do
-
- Normal: The next visit at the interval your dentist sets.
- Abnormal: A treatment plan; our dental cleaning article explains what a deep cleaning is.
- Notes
-
- Dental packages are listed under Specialty Care.
Which tests depend on your history?
These depend on something about you: smoking, a family history, where you were born, or a pregnancy you are planning. Without that reason they are not screening.
Coronary artery calcium (CAC) CT — from 45
- When
- Once, when the statin decision is uncertain (a 10-year risk of 3% to under 10%); repeat in 3–7 years if the score is 0.
- Why it is worth doing
- A calcium score of 0 lets many people at intermediate risk safely defer a statin; a score of 100 or more makes the case for one. The 2026 ACC/AHA guideline gives CAC a class 1 recommendation for intermediate-risk and selected borderline-risk adults, men from 40 and women from 45.
- What the result lets you do
-
- Normal: A score of 0: defer the statin and repeat the CAC in 3–7 years — unless you have diabetes over 40, smoke, have an LDL of 190 or more, or a strong family history.
- Borderline: 1–99 and below the 75th percentile: a moderate-intensity statin is reasonable, LDL under 100.
- Abnormal: 100 or more, or the 75th percentile or above: cholesterol-lowering treatment is recommended — LDL cut by at least half and under 70; 300 and 1,000 have lower targets still.
- Notes
-
- Not for people already on a statin or with known heart disease.
- Radiation dose: see the exam page.
- Read more
- Coronary artery calcium (CAC) CT: what it finds, who it is for, and what to expect
Upper endoscopy (gastroscopy) — from 40
- When
- No US screening guideline. Japan screens from 50 and Korea from 40, every 2 years.
- Why it is worth doing
- Stomach cancer is common enough in East Asia that Japan (50 and over, X-ray or endoscopy every 2 years) and Korea (40 and over, endoscopy every 2 years) run national programs; the US has none and Taiwan has no population gastroscopy program. It is worth considering if you were born in East Asia, have a family history, or are already having a colonoscopy under sedation.
- What the result lets you do
-
- Normal: Repeat only if a risk factor remains.
- Borderline: Gastritis, intestinal metaplasia or H. pylori on biopsy: treat H. pylori; the pathology sets any surveillance interval.
- Abnormal: The biopsy result and a specialist.
- Read more
- Upper endoscopy (gastroscopy): what it finds, who it is for, and what to expect
H. pylori test (breath or stool antigen)
- When
- Once, for a reason; retest at least 4 weeks after treatment to confirm the cure.
- Why it is worth doing
- H. pylori causes ulcers and most stomach cancers. The ACG (2024) lists a family history of stomach cancer, being foreign-born from a high-incidence region and living with an infected person among the reasons to test. Taiwan now offers everyone 45–74 a one-time stool test (from 2026).
- What the result lets you do
-
- Normal: Negative: done, unless you were on acid reducers or antibiotics, which cause false negatives — repeat off them.
- Abnormal: Positive: an antibiotic course, then a breath or stool test of cure at least 4 weeks later.
- Notes
-
- A blood antibody test cannot tell a past infection from a current one.
- Read more
- H. pylori test (breath or stool antigen): what it finds, who it is for, and what to expect
Fertility check (AMH and hormone panel; semen analysis) — until 45
- When
- If you are planning a pregnancy: the ASRM says to be evaluated after 12 months of trying when the female partner is under 35, and after 6 months at 35 or older.
- Why it is worth doing
- Fertility falls with age, and the tests show where things stand before time is lost. The ASRM definition of infertility sets the clock: 12 months of trying under 35, 6 months at 35 and over.
- What the result lets you do
-
- Normal: Keep trying; return at the ASRM timing.
- Abnormal: A reproductive endocrinologist — options are widest the earlier you go.
- Notes
-
- AMH reflects egg supply; on its own it does not predict the chance of natural conception. See the exam page.
- Read more
- Fertility check (AMH and hormone panel; semen analysis): what it finds, who it is for, and what to expect
Which popular tests have weak evidence at this age?
These sell well and carry a grade I (evidence insufficient) or D (recommended against) from the USPSTF or the ACR. The result column says what a finding would mean if you have one anyway.
Full-body skin exam
- When
- No guideline interval.
- Why it is worth doing
- The USPSTF finds the evidence insufficient for routine whole-body skin exams in people without symptoms (2023, grade I). It is reasonable if you have many moles, fair skin, heavy sun exposure or a family history of melanoma.
- What the result lets you do
-
- Normal: Self-checks; see a dermatologist for a changing mole.
- Abnormal: A biopsy decides.
- Notes
-
- A full-body skin exam is listed under Specialist Care.
Thyroid ultrasound
- When
- Not recommended as screening.
- Why it is worth doing
- The USPSTF recommends against screening for thyroid cancer in adults without symptoms (2017, grade D): ultrasound finds nodules in about half of people by 60, nearly all harmless, and screening leads to surgery without lowering deaths. Thyroid function (TSH) screening is a separate question with insufficient evidence (2015, grade I).
- What the result lets you do
-
- Normal: Nothing.
- Borderline: A small nodule: TI-RADS rules usually mean no biopsy and no follow-up. See the thyroid ultrasound page.
- Abnormal: A suspicious nodule: a needle biopsy decides.
- Notes
-
- Reasonable if you had neck radiation as a child or have a family history of thyroid cancer.
- Read more
- Thyroid ultrasound: what it finds, who it is for, and what to expect
Tumor-marker blood tests (CA-125, CEA, AFP, CA 19-9) and ovarian screening
- When
- Not recommended as screening.
- Why it is worth doing
- Screening with CA-125 and ultrasound does not reduce ovarian-cancer deaths and causes surgery for false positives (USPSTF 2018, grade D); pancreatic-cancer screening is also a D. CEA, AFP and CA 19-9 rise with many benign conditions and miss early cancers, so a panel of them is not a cancer screen.
- What the result lets you do
-
- Normal: Nothing.
- Abnormal: A raised marker without symptoms usually means more tests, not cancer. See the tumor-marker page.
- Notes
-
- Different for women with a BRCA mutation or a strong family history — a genetics-clinic question.
- AFP with ultrasound every 6 months is a surveillance test for cirrhosis and for hepatitis B carriers in the AASLD groups, not a screening test.
- Read more
- Tumor-marker blood tests (CA-125, CEA, AFP, CA 19-9) and ovarian screening: what it finds, who it is for, and what to expect
Whole-body MRI
- When
- Not recommended for people without symptoms (ACR 2023).
- Why it is worth doing
- The American College of Radiology finds no evidence to justify whole-body MRI or CT screening of people with no symptoms, risk factors or family history: incidental findings are common, and each one leads to more tests before it proves harmless.
- What the result lets you do
-
- Normal: Nothing. A normal survey is not an all-clear.
- Borderline: An incidental finding: most are benign; follow the radiologist's recommendation, usually a repeat scan at an interval.
- Abnormal: A targeted workup of that organ.
- Notes
-
- The full-body MRI page lays out what it can and cannot find.
- Read more
- Whole-body MRI: what it finds, who it is for, and what to expect
Carotid ultrasound
- When
- Not recommended as screening.
- Why it is worth doing
- The USPSTF recommends against screening for carotid narrowing in the general adult population (2021, grade D): a positive result leads to procedures whose risks outweigh the stroke-prevention benefit in people without symptoms.
- What the result lets you do
-
- Normal: Nothing.
- Borderline: Plaque without significant narrowing: treat the risk factors you already know about; no procedure.
- Abnormal: Significant stenosis: a vascular specialist, but surgery is rarely advised without symptoms.
- Read more
- Carotid ultrasound: what it finds, who it is for, and what to expect
Resting ECG
- When
- Not recommended as screening in low-risk adults.
- Why it is worth doing
- The USPSTF recommends against a screening ECG in adults at low cardiovascular risk (2018, grade D) and finds the evidence insufficient at intermediate or high risk (grade I): it adds little to a risk calculation and leads to more tests.
- What the result lets you do
-
- Normal: Nothing.
- Abnormal: Most abnormal screening ECGs are benign variants; a cardiologist decides whether anything follows.
- Notes
-
- Screening for atrial fibrillation at 50 and over is also a grade I (2022).
- Read more
- Resting ECG: what it finds, who it is for, and what to expect
Home sleep study
- When
- Only with symptoms.
- Why it is worth doing
- The evidence is insufficient for sleep-apnea screening in people without symptoms (USPSTF 2022, grade I). Loud snoring, witnessed pauses or daytime sleepiness are reasons to test.
- What the result lets you do
-
- Normal: Nothing.
- Abnormal: A sleep physician; CPAP or an oral device.
- Read more
- Home sleep study: what it finds, who it is for, and what to expect
Which nutrients does the report check, and how much do you need at this age?
A screening blood panel reports a few nutrient lines, and most reports do not explain them. The table gives the recommended daily intake for women aged 40–49 (NIH Office of Dietary Supplements) and what a low value means; the nutrient blood tests page has the cut-offs, food sources and the supplement rules in full.
| Nutrient | Recommended daily intake | What a low value means | When a supplement is the answer |
|---|---|---|---|
| Vitamin D (25-hydroxyvitamin D) | 600 IU (15 mcg) | Under 12 ng/mL (30 nmol/L) is deficient; 12 to under 20 ng/mL is inadequate for bone; 20 or more is adequate; over 50 ng/mL is linked to adverse effects (NIH ODS). | The Endocrine Society (2024) suggests routine supplementation for adults 75 and over, in pregnancy and with prediabetes, and not for healthy adults 19–74; everyone should meet the RDA. The upper limit is 4,000 IU a day. |
| Vitamin B12 | 2.4 mcg | Most laboratories call under 200–250 pg/mL subnormal; 150–399 pg/mL is a grey zone where an MMA test (over 0.271 micromol/L) or homocysteine (over 15 micromol/L) settles it (NIH ODS). | For a measured low level, a vegan diet, or an absorption problem such as pernicious anemia or stomach surgery (NIH ODS risk groups). B12 has no upper limit. |
| Folate | 400 mcg DFE | A serum folate over 3 ng/mL and a red-cell folate over 140 ng/mL mean adequate status; NIH ODS gives adequacy cut-offs, not a deficiency line. | Anyone who could become pregnant: 400–800 mcg of folic acid a day from at least one month before conception (USPSTF 2023, grade A); the CDC says 400 mcg of folic acid even with an MTHFR variant. The upper limit from supplements and fortified foods is 1,000 mcg. |
| Calcium | 1,000 mg | A blood calcium level (normal 8.8–10.4 mg/dL) does not reflect your calcium status — bone holds it; the DEXA scan is the cumulative read (NIH ODS). Under 8.5 or over 10.5 mg/dL is a medical question, not a diet one. | Only to close the gap between diet and the RDA; doses of 500 mg or less absorb best. The upper limit is 2,500 mg at 19–50 and 2,000 mg from 51. |
| Iron (hemoglobin on the CBC; ferritin) | 18 mg | A ferritin under 30 mcg/L suggests iron deficiency and under 10 iron-deficiency anemia; a hemoglobin under 12 g/dL (age 10 and over) suggests anemia. Inflammation raises ferritin, so a normal ferritin with symptoms is not the end (NIH ODS). | For a confirmed deficiency, or in pregnancy (ACOG: low-dose iron from the first trimester). The upper limit is 45 mg; vegetarians need 1.8 times the RDA. |
| Homocysteine | No RDA — a marker, not a nutrient | 5–15 micromol/L is the usual normal range; above 15 suggests a B12 or folate shortfall, but kidney function and other factors raise it too. | None on its own. A high value is a reason to check B12 and folate, not a reason to take anything. |
Iron stays a priority until periods stop; calcium and vitamin D matter more as bone loss begins.
What do you do with the report?
Every row above says what its own result changes. The pattern is the same for all of them, and it is the reason to screen at all:
- Normal: the report sets the date of the next test — nothing else. Keep it; trends across years say more than any single result.
- Borderline: a repeat test, a lifestyle change with a date to recheck, or one more targeted test. A borderline value is a question, not a diagnosis.
- Abnormal: the report names the next test or the specialist. If it was found abroad, our guide to what follow-up costs explains how to take the result home.
The next decade adds: Low-dose lung CT (from 50); Hearing test (from 50).
