What changes in your 20s?
Nothing in your 20s is a cancer screen except the Pap smear, and that is the point of this decade: it is when the numbers that will drive every later decision get their first reading. A lipid panel at 19 and a one-time lipoprotein(a) test tell you how much of your heart risk is inherited. A blood-pressure reading every few years catches the one condition that is common, silent and cheap to treat.
It is also the decade that decides your bone account. Peak bone mass is reached by about 30, and what you bank now is what a DEXA scan will measure at 65. The hepatitis and HIV tests are once in a lifetime; the result changes nothing for most people and everything for a few. If pregnancy is possible, folic acid is the one supplement with an A grade.
Which screenings are recommended for women aged 18–29?
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
Cervical screening (Pap smear; HPV test where available) — from 21
- 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.
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)
- 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 18–29 (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 | 1,300 mg to 18; 1,000 mg from 19 | 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) | 15 mg to 18; 18 mg from 19 | 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. |
The Dietary Guidelines 2025–2030 put peak bone mass, iron and folate at the centre of young adulthood for women.
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: HbA1c and fasting glucose (from 35).
