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Preventive Health

Table of Contents

What is preventive health?
Three levels of prevention
Evidence-based screening recommendations
Lifestyle as medicine

What is preventive health?

Preventive health means taking action to avoid disease before it starts rather than treating illness after symptoms appear. The World Health Organization reports that noncommunicable diseases like cardiovascular conditions, cancers, and diabetes account for 75% of all deaths globally, yet many of these conditions can be prevented or delayed through lifestyle changes and early detection ^[1].

Three levels of prevention

Primary prevention keeps healthy people from getting sick in the first place. This includes regular exercise, balanced nutrition, adequate sleep, stress management, and avoiding tobacco. The Centers for Disease Control and Prevention identifies four key risk factors for chronic disease: tobacco use, poor nutrition, physical inactivity, and excessive alcohol consumption ^[2]. Addressing these factors simultaneously reduces risk across multiple conditions.

Secondary prevention catches disease early when treatment works best. Systematic reviews show that evidence-based screening programs significantly improve outcomes for conditions where early detection matters. Breast cancer screening through mammography, colorectal screening beginning at age 45, and cardiovascular risk assessments all fall into this category ^[3].

Tertiary prevention manages existing conditions to stop them from getting worse. This includes medication adherence, rehabilitation programs, and ongoing monitoring to prevent complications.

Evidence-based screening recommendations

A 2024 systematic review from JAMA found that screening mammography reduces breast cancer mortality, with updated guidelines recommending women begin screening at age 40 ^[4]. For prostate cancer, PSA testing shows a small reduction in disease-specific mortality but requires careful discussion of potential harms including overdiagnosis and treatment complications ^[5].

The most effective approach combines multiple screening modalities based on age, family history, and individual risk factors. Risk stratification tools help identify who benefits most from intensive screening versus routine care.

Lifestyle as medicine

Physical activity recommendations from major health organizations call for at least 150 minutes of moderate exercise weekly plus strength training twice weekly. Dietary patterns emphasizing vegetables, fruits, whole grains, and lean proteins while limiting processed foods and added sugars reduce metabolic risk factors including blood pressure, cholesterol, and blood sugar.

Sleep quality matters too. Adults need 7-9 hours nightly, and insufficient sleep links to obesity, diabetes, cardiovascular disease, and depression ^[2].

References

Move for prevention

Aim for 150 minutes of moderate activity weekly. Regular exercise reduces risk of heart disease, type 2 diabetes, and several cancers. Even walking counts.

www.cdc.gov

Track your numbers

Know your blood pressure, cholesterol, fasting glucose, and BMI. These metabolic markers predict future disease risk. Small improvements make meaningful differences.

Prioritize sleep

Aim for 7-9 hours of quality sleep. Sleep deprivation disrupts reproductive hormones in both men and women. Men produce testosterone during sleep. Women need adequate sleep for proper estrogen and progesterone cycles.

Annual checkup checklist

Beyond basics: request comprehensive blood work, check blood pressure, get skin checked for moles, and discuss cancer screenings appropriate for your age and family history.

Know your screening ages

Colonoscopy at 45 (earlier with family history), mammography at 40-50, skin checks annually, dental every 6 months. Proactive screening catches 90%+ of cancers at treatable stages.

How often should I get a physical exam?

Healthy adults under 40 typically need an exam every 2-3 years. After 40, annual checkups become more important. However, individual factors like family history, chronic conditions, or lifestyle risks may require more frequent visits. Talk to your doctor about the right schedule for you.

Which lifestyle changes have the biggest impact on prevention?

The four highest-impact changes are: quitting smoking (reduces risk of heart disease, cancer, and lung disease), regular physical activity (150 minutes weekly), eating a plant-forward diet with minimal processed foods, and getting 7-9 hours of quality sleep. Together, these address the root causes of most preventable chronic diseases.

What health screenings do I need by age?

By 20s: baseline blood work, skin checks. By 30s: comprehensive metabolic panel, thyroid, STD screening. By 40s: cardiovascular risk assessment, mammography (women), PSA baseline (men), eye exam. By 45: colonoscopy. By 50s: bone density (women), expanded cancer screenings. Earlier if family history warrants it. Proactive screening catches 90%+ of cancers at treatable stages.

What is the difference between conventional and functional medicine?

Conventional medicine focuses on diagnosing and treating disease after it manifests. Functional medicine aims to identify and address root causes before disease develops, using broader lab testing and lifestyle interventions. Neither is universally better — conventional medicine excels at acute care and emergencies, while functional medicine shines in prevention and optimization. Ideally, use both.