Optimal, not minimum
Screening guidelines from bodies such as the US Preventive Services Task Force are written for whole populations. They weigh benefit against cost, capacity, and the harms of testing millions of people, so they often set a floor: a lipid panel at least every five years, diabetes screening every three years from 35, colorectal screening from 45. Someone who wants to stay healthy for decades, and can get care, can do better.
This guide leads with the optimal plan, drawn from prevention-focused specialty societies, trials, and clinicians who practice prevention, and shows the guideline minimum second so you can see the difference. Optimal is not maximal. When more testing finds more false alarms than real disease, as with whole-body CT or yearly thyroid ultrasounds, the guide says to skip it. See Reading the evidence for how the grades work.
The ten things that matter most
Roughly in order of how much they matter for the average adult. The chapter linked from each one explains the evidence and the details.
- Don't smoke or vape. Smoking multiplies lung cancer risk about 25-fold and damages almost every organ. Quitting helps at any age, and the earlier the better. See Avoiding harm.
- Build fitness and strength, and keep them. In a study of 122,007 people who took treadmill tests, the least fit quarter died at five times the rate of the fittest few percent. Aim for 3–4 hours of easy zone 2 work, one or two hard interval sessions, three strength sessions, and a few minutes of balance work most days, and test your VO2 max in a lab once a year. That is two to four times the guideline minimum of 150 minutes and two strength days, which is where to start, not where to stop. See Exercise.
- Keep your blood pressure under 120/80. It is the largest single contributor to heart attacks, strokes, kidney disease, and dementia, and it is almost entirely treatable. Measure it at home on a validated cuff for a week every few months. See Heart and blood vessels.
- Drive ApoB down early, and measure Lp(a). Atherosclerosis is driven by lifetime exposure to cholesterol-carrying particles, so the lower and earlier, the better. Check ApoB every year. See Heart and blood vessels.
- Protect your metabolic health. Keep your waist under half your height, and check HbA1c and fasting insulin every year to catch insulin resistance years before diabetes. See Metabolic health.
- Sleep seven to nine hours, at the same times every day. If you snore regularly, have high blood pressure, or wake up unrefreshed, get a home sleep test. See Sleep.
- Eat mostly whole foods. Protein at every meal, plenty of fiber and vegetables, little ultra-processed food, and no alcohol, or as little as you can live with. See Nutrition.
- Stay connected, and treat depression. Loneliness and untreated depression raise the risk of heart disease and early death. See Mind and connection.
- Screen early and stay vaccinated. Breast, colorectal, cervical, prostate, skin, and lung cancer screening, started at the right age for your risk, and adult vaccines are among the best-proven ways to live longer. See the prevention checklist.
- Avoid preventable injury. Seatbelts, helmets, undistracted driving, fall-proofing your home, and testing for radon. See Avoiding harm.
The numbers to know
These are the measurements worth tracking, the target to aim for, and how often to check. The guideline column shows the standard-of-care threshold for comparison. The linked chapters explain each one.
| Number | Optimal target | How often | Guideline threshold | Chapter |
|---|---|---|---|---|
| Blood pressure | Below 120/80 on home readings | A week of home readings every 3 months; most days while adjusting treatment | Treat at 130/80 or higher | Heart |
| ApoB | Below about 60 mg/dL; lower with plaque, heart disease, or high risk | Every year; 4–12 weeks after each treatment change | Measured selectively | Heart |
| LDL cholesterol | Below about 70 mg/dL | With ApoB | Goal depends on 10-year risk | Heart |
| Lipoprotein(a) | Know your number | Once, with your first adult lipid panel | Measure once | Heart |
| HbA1c and fasting glucose | HbA1c below about 5.5%; fasting glucose in the 70s to mid-80s mg/dL | Every year from your 20s; every 3 months while changing something | Below 5.7% is normal; screen every 3 years from 35 | Metabolic health |
| Fasting insulin | Single digits (µIU/mL), with HOMA-IR under about 2 | Every year | Not recommended | Metabolic health |
| Waist | Less than half your height | Every few months | Waist cutoffs of 40 inches for men and 35 for women | Metabolic health |
| Kidney function | eGFR from creatinine and cystatin C in the normal range; urine albumin under 30 mg/g | Every year | Test only with diabetes or high blood pressure | Blood tests |
| VO2 max | At or above the 90th percentile for your age and sex; the top 2.5% is the stretch goal | A lab test every year; a field test every 3 months | No target | Exercise |
| Lean mass and bone density | Lean mass in the top quarter for your age and sex; normal bone density | A body-composition DEXA every 1–2 years from your 30s or 40s; a hip-and-spine scan in your 40s | Bone density for women from 65 | Muscle, bone, and mobility |
| Sleep | Seven to nine hours asleep, with bedtime and wake time within about 30 minutes every day | Two weeks of tracking once or twice a year | Seven or more hours | Sleep |
| Steps | 7,000–10,000 a day | Track continuously | No target | Exercise |
What to start at each age
The prevention checklist has the full, personalized list with sources. These are the milestones people most often miss.
| Age | Start or schedule |
|---|---|
| 20s | A yearly lab panel with ApoB, HbA1c, kidney and liver markers, and a one-time Lp(a); home blood pressure checks; HIV and hepatitis C screening once; a breast cancer risk assessment for women by 25; cervical screening with an HPV test every 5 years from 25; the HPV vaccine; eye exams every 2 years; dental cleanings every 6 months; monthly skin self-checks; and the training habits that will carry you for decades |
| 30s | A one-time clinical-grade genetic panel for inherited cancer risk, ideally by 30; a baseline DEXA scan and VO2 max test; a written three-generation family history; a home sleep test if you snore; and lipid-lowering treatment if ApoB stays high despite lifestyle changes |
| 40s | Mammograms every year from 40; a first colonoscopy at 40, repeated every 5 years if normal, with an endoscopist who finds polyps often; a baseline PSA by 45 (40 at higher risk); a coronary calcium scan (men about 40, women about 45, earlier with family history or high Lp(a)); a dilated eye exam and a hearing test by 40; a dermatologist skin exam every 2 years; and, for women, a plan for menopause before symptoms peak |
| 50s | The shingles and pneumococcal vaccines from 50; a brief cognitive baseline test; and lung cancer screening from 50 if you have 20 or more pack-years of smoking, however long ago you quit |
| 60s and older | The RSV vaccine from 60; yearly hearing tests from 60; yearly eye exams and cognitive checks from 65; balance training and fall prevention; a yearly medication review; and an aortic ultrasound for men 65–75 who ever smoked. See Aging well after 65 |
Where to spend money, and where not to
The best-proven prevention is cheap or free. Spend in roughly this order.
- Free The yearly preventive visit, guideline screenings, and most vaccines are covered without cost sharing by most US insurance. See Building your care team.
- Under $100 A validated upper-arm blood pressure cuff, a connected scale, adjustable dumbbells or a gym membership, and walking shoes.
- A few hundred dollars a year Whatever your insurance won't cover of a yearly lab panel (ApoB, Lp(a), fasting insulin, cystatin C), a DEXA scan, a VO2 max test, and a coronary calcium scan at the right age.
- Optional extras Full-body MRI and multi-cancer blood tests cost $1,000 or more, are unproven to save lives, and generate false alarms. If you choose them, use them on top of guideline screening, never instead of it. See Cancer.
How this guide is organized
- Start here: what aging is, why it drives disease, and how to judge the evidence.
- Daily habits: exercise, nutrition, sleep, mind and connection, and avoiding harm.
- Prevent disease: one chapter for each of the conditions that end or diminish most lives.
- Measure and monitor: the checklist, blood tests, scans, wearables, and the people who help you act on them.
- Medicine: longevity drugs, supplements, and hormones, graded by the human evidence.
- Life stages: what is different for women, for men, and after 65.
- Putting it together: what I do, where to learn more, and the vocabulary.
Every recommendation carries an evidence grade, from Strong to Negative, and every specific claim links to its source.