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Tools of Prevention


Magda Lenartowicz

, MD, Altais Health Solutions

Reviewed/Revised May 2023
Topic Resources

There are many tools of prevention, including the following major tools:

Preventive medication therapy includes the following:

Did You Know...

  • Eating a healthy diet, exercising regularly, and stopping smoking help prevent all three leading causes of death in the United States (heart disease, cancer, and stroke).

Healthy Lifestyle

Lifestyle and disease are clearly linked. For example, eating an unhealthy diet Diet Atherosclerosis is a condition in which patchy deposits of fatty material (atheromas or atherosclerotic plaques) develop in the walls of medium-sized and large arteries, leading to reduced or... read more Diet (high in calories, saturated fats, and trans fatty acids and deficient in certain other nutrients), not exercising regularly, and smoking increase the risk of developing heart disease Overview of Coronary Artery Disease (CAD) Coronary artery disease is a condition in which the blood supply to the heart muscle is partially or completely blocked. The heart muscle needs a constant supply of oxygen-rich blood. The coronary... read more Overview of Coronary Artery Disease (CAD) , cancer Prevention of Cancer Although there are many different types of cancer, which have different causes and risk factors, doctors estimate that about 40% of cancers are preventable. Also, individual people have different... read more , and stroke Overview of Stroke A stroke occurs when an artery to the brain becomes blocked or ruptures, resulting in death of an area of brain tissue due to loss of its blood supply (cerebral infarction). Symptoms occur suddenly... read more —the three leading causes of death in the United States. Changing unhealthy lifestyle habits can help prevent particular disorders and/or improve fitness and quality of life. Talking with doctors and other health care professionals can help people make good decisions and establish healthy habits. However, establishing and maintaining a healthy lifestyle can be done only by the person. Consistently eating a healthy diet and getting enough exercise are difficult for many people, but people who do so reduce their risk of developing serious disorders and often feel better and have more energy.

Physical activity and exercise Benefits of Exercise Regular exercise makes the heart stronger and the lungs fitter, enabling the cardiovascular system to deliver more oxygen to the body with every heartbeat and the pulmonary system to increase... read more can help prevent obesity Obesity Obesity is a chronic, recurring complex disorder characterized by excess body weight. Obesity is influenced by a combination of factors that includes genetics, hormones, behavior, and the environment... read more Obesity , high blood pressure High Blood Pressure High blood pressure (hypertension) is persistently high pressure in the arteries. Often no cause for high blood pressure can be identified, but sometimes it occurs as a result of an underlying... read more High Blood Pressure , heart disease Overview of Coronary Artery Disease (CAD) Coronary artery disease is a condition in which the blood supply to the heart muscle is partially or completely blocked. The heart muscle needs a constant supply of oxygen-rich blood. The coronary... read more Overview of Coronary Artery Disease (CAD) , stroke Overview of Stroke A stroke occurs when an artery to the brain becomes blocked or ruptures, resulting in death of an area of brain tissue due to loss of its blood supply (cerebral infarction). Symptoms occur suddenly... read more , diabetes Diabetes Mellitus (DM) Diabetes mellitus is a disorder in which the body does not produce enough or respond normally to insulin, causing blood sugar (glucose) levels to be abnormally high. Symptoms of diabetes may... read more , some types of cancer, constipation Constipation in Adults Constipation is difficult or infrequent bowel movements, hard stool, or a feeling that the rectum is not totally empty after a bowel movement (incomplete evacuation). (See also Constipation... read more , falls Falls in Older Adults , and other health problems. The best routine includes moderate physical activity for a total of 150 minutes per week, or vigorous aerobic activity for 75 minutes per week (or a combination of the two). Exercise periods should be at least 10 minutes long and ideally spread throughout the week. However, getting even a little bit of exercise is much better than none at all. For example, people who can devote only 10 minutes to physical activity a few times per week may still reap important benefits, particularly if the exercise is vigorous. Walking is one simple, effective exercise that many people enjoy. Certain types of exercise can also target specific problems. For example, stretching improves flexibility, which can help prevent falls Falls in Older Adults A fall is defined as unintentionally or accidentally dropping down to the ground or another lower level. Most falls occur when older adults with one or more physical conditions that impair mobility... read more . Aerobic exercise may decrease the risk of heart attack Acute Coronary Syndromes (Heart Attack; Myocardial Infarction; Unstable Angina) Acute coronary syndromes result from a sudden blockage in a coronary artery. This blockage causes unstable angina or a heart attack (myocardial infarction), depending on the location and amount... read more Acute Coronary Syndromes (Heart Attack; Myocardial Infarction; Unstable Angina) and angina Angina Angina is temporary chest pain or a sensation of pressure that occurs while the heart muscle is not receiving enough oxygen. A person with angina usually has discomfort or pressure beneath the... read more .

Quitting smoking Treatment Most people who smoke want to quit and have tried doing so with limited success. Effective tools to help quit smoking include counseling, nicotine replacement products, and medications. While... read more is important to a healthful lifestyle. A doctor can offer encouragement and advice on ways to successfully quit smoking, including information and recommendations on the use of nicotine replacement products, bupropion and varenicline (medications that help reduce cravings), and other tools.

Limiting alcohol use Alcohol Use Alcohol (ethanol) is a depressant (it slows down brain and nervous system functioning). Consuming large amounts rapidly or regularly can cause health problems, including organ damage, coma,... read more is important. The Centers for Disease Control and Prevention (CDC) recommends that adults of legal drinking age either not drink any alcohol or limit the amount to 2 drinks or less in a day for men or 1 drink or less in a day for women on days when alcohol is consumed. (Each drink is about 12 ounces of beer, 5 ounces of wine, or 1.5 ounces of more concentrated liquor, such as whiskey.) Whether drinking, even small amounts of alcohol, has any health benefits is unclear. Also, drinking even small amounts of alcohol may increase the risk of harmful effects.

Preventing injuries is crucial to maintaining a healthful lifestyle. People can lower their risk of injury by taking certain precautions, such as wearing appropriate protective equipment (including seat belts). For older people,the following can help reduce the risk of falling:

  • Removing throw rugs

  • Having good lighting at home

  • Exercising (especially to improve balance and muscle strength)

  • Having vision checked regularly, getting the correct glasses, and wearing them

  • Having a doctor, nurse, or pharmacist review all medications that can contribute to falls whenever prescriptions are added or changed

Safety 101

Simple, common-sense safety measures can help prevent injuries. The following are some examples:

General Safety

Home Safety

To prevent falls and fall-related injuries in children:

  • Install safety locks on basement doors.

  • Close and lock windows when children are present.

  • Replace or cover sharp-edged furniture.

  • Do not use baby walkers.

  • Install window guards, especially above the first floor.

  • Use stair gates at the top and bottom of stairs.

  • Never mix cleaning products.

  • Keep oven and toilet bowl cleaners, pesticides, alcohol, and antifreeze tightly sealed and out of the reach of children.

  • Keep all medications in their original containers, and use child protective pill containers if small children are part of the household or are visiting.

  • Follow instructions on how to safely dispose of expired medications and medications that are no longer necessary (see How to Dispose of Unused Medicines available at the Food and Drug Administration's web site).

To prevent fires:

  • Install operational smoke detectors on every floor in the home, including the basement, and in every bedroom.

  • Test batteries every month and install new batteries every 6 months.

  • Plan an escape route and practice it.

  • Keep a fire extinguisher in or near the kitchen.

  • Have the electrical system inspected by a professional.

  • Do not leave lit candles unattended.

  • Do not smoke in bed.

  • Ensure adequate ventilation for indoor sources of combustion (such as furnaces, hot-water heaters, wood- or charcoal-burning stoves, and kerosene heaters).

  • Clean flues and chimneys regularly and inspect them for leaks.

  • Use a carbon monoxide detector in the home.

To prevent exposure to radon:

  • Have the radon level in the home checked.

  • Ensure adequate ventilation, especially in the basement.

  • Consult the local health department and ask how to detect toxic levels of lead in the home’s drinking water.

  • Find out whether the paint in the house is lead-based (present in older houses), and if there is any question, test paint chips.

  • Test ceramic dishes made outside the United States for lead.

  • Have children tested for lead levels if recommended by their doctor.

  • Set the maximum hot water heater temperature at 130° F (54.44° C) or less.

Food Safety

  • Pay attention to “use by” dates on packaging.

  • Refrigerate perishable food immediately.

  • Do not buy dented canned goods or anything with a loose or bulging lid.

  • Keep the refrigerator at 40° F (4.44° C) and the freezer at 0° F (-17.78° C).

  • Freeze fresh meats (including fish and poultry) that will not be used in 2 days.

  • Do not let the juices from raw meats drip on other foods.

  • Wash hands before and after preparing food.

  • Cook foods thoroughly.

  • Do not use the same utensils or platters for raw and cooked meats.

  • Wash all countertops, cutting boards, and utensils in hot soapy water after use.

Car Safety

  • Obey speed limits and drive defensively.

  • Make sure all passengers wear seat belts.

  • Put children in car seats or other restraints appropriate for their height and weight.

  • Do not allow a baby or child to sit on someone’s lap in a moving vehicle.

  • Do not drink alcohol and do not use recreational drugs or medications that cause drowsiness before driving.


Vaccines Childhood Vaccinations Vaccination protects children against many infectious diseases. Vaccines contain either noninfectious components of bacteria or viruses or whole forms of these organisms that have been weakened... read more have been enormously successful. Dangerous and sometimes fatal infectious diseases such as diphtheria, pertussis, tetanus, mumps, measles, rubella, and polio have decreased by more than 99% from their peak number of cases, thanks to the availability of effective and safe vaccines and their widespread use. Furthermore, vaccinations save about $16 in health care costs for every $1 spent.

Many side effects have been attributed to vaccines (see Childhood Vaccination Concerns Childhood Vaccination Concerns Despite the strong vaccine safety systems in place in the United States, some parents remain concerned about the use and schedule of vaccines in children. These concerns can lead some parents... read more ). Actual side effects that occur depend on the vaccine, but common side effects are usually minor and include swelling, soreness, and allergic reactions at the injection site, and sometimes fever or chills. More serious side effects can occur. They include autoimmune reactions (for example, Guillain-Barré syndrome Guillain-Barré Syndrome (GBS) Guillain-Barré syndrome is a form of polyneuropathy causing muscle weakness, which usually worsens over a few days to weeks, then slowly improves or returns to normal on its own. With treatment... read more , which causes temporary weakness or paralysis). However, serious side effects are very rare if vaccines are used appropriately.

Systematic and extensive research has found no link between vaccines and other serious side effects such as autism. Reports that vaccines cause AIDS or sterility are urban legends and have no factual basis. Refusing vaccination to avoid side effects increases the risk of getting an infection, which is a much greater threat to health than are possible side effects of vaccination.

Did You Know...

  • Vaccinations can benefit people other than those receiving the vaccine.

Children and adolescents, older adults, and people whose immune system is impaired are often the most vulnerable to infections that vaccines can prevent. If these people get such infections, they are also often the most likely to have serious symptoms. For example, whooping cough (pertussis) tends to cause severe symptoms in infants but can be as mild as a cold in older, otherwise healthy people. Although it is most important to vaccinate the most vulnerable people, vaccinating other people is also important. Doing so not only prevents illness in the vaccinated person but also reduces the number of people in the community who could develop and thus transmit infection to more vulnerable people. Thus, deaths and serious complications in the community are reduced by vaccinating as many people as possible. This effect is called herd immunity.


Screening is testing of people who are at risk of a disorder but do not have any symptoms (see also Medical Testing Decisions, Screening Tests Screening tests Because many different diseases can cause the same symptoms, it can be challenging for doctors and other primary care practitioners to identify the cause. Doctors first gather basic information... read more ). Screening can enable doctors to detect a disorder early and to start treatment early. Early treatment sometimes keeps disorders from turning deadly. For example, abnormalities of the cervix or colon can be diagnosed and cured before they become cancerous.

Screening programs have greatly reduced the number of deaths caused by some disorders. For example, deaths due to cervical cancer, once the most common cause of cancer death among American women, have decreased 75% since 1955. However, the decrease varies from area to area, depending on availability and affordability of screening and other factors. Screening can also detect disorders that cannot be cured but that can be treated before they cause too much damage (for example, high blood pressure High Blood Pressure High blood pressure (hypertension) is persistently high pressure in the arteries. Often no cause for high blood pressure can be identified, but sometimes it occurs as a result of an underlying... read more High Blood Pressure ).

Screening recommendations usually come from government or professional organizations and are based on the best available research. However, different organizations sometimes make different recommendations. There are several reasons for different recommendations. Even the best research results are not always conclusive. Also, screening recommendations must take into account how much risk and how much expense people are willing to accept, factors that cannot be known with certainty. Thus, decisions about screening are individualized. People should discuss screening with their doctor to determine what is best for them.

Did You Know...

  • Some tests to diagnose disorders before symptoms occur (screening tests) can potentially cause more harm than good.

People may think that any test capable of detecting a serious disorder should be done. Screening can offer great benefits. However, it can also create problems. For example, screening test results are sometimes positive in people who do not have disease. As a result, some of these people then have additional follow-up tests and/or treatments that are unnecessary, often expensive, and sometimes painful or dangerous.

Also, sometimes screening detects abnormalities that cannot or need not be treated. For example, prostate cancer Prostate Cancer Prostate cancer begins in the prostate gland, an organ found only in males. The risk of prostate cancer increases as men age. Symptoms, such as difficulty urinating, a need to urinate frequently... read more Prostate Cancer often grows so slowly that in older men, the cancer is unlikely to affect their health before they die from another cause. In such cases, the treatment can be worse than the disease. Another example involves using whole-body computed tomography (CT) to screen everyone for cancer. This approach is not recommended because it does not have benefits (such as saving lives) that exceed the risks (such as developing disorders caused by the radiation exposure, including cancer). In addition, when people are told they might have a serious disorder, they can become anxious, and anxiety can affect health.

Because of these issues, screening is recommended only when

  • The person has some real risk of developing the disorder.

  • The screening test is accurate.

  • The disorder can be more effectively treated when it is diagnosed before symptoms develop.

  • The health care benefits of appropriate screening make it relatively cost effective.

Some screening tests (such as tests for cervical and colon cancers) are recommended for all people of a certain age or sex. For people at increased risk because of other risk factors, tests may be recommended at an earlier age or at more frequent intervals than is recommended for people at average risk, or additional tests may be recommended. For example, a person with a family history of colorectal cancer or with a disease that increases the chances of developing colorectal cancer Colorectal Cancer Family history and some dietary factors (low fiber, high fat) increase a person’s risk of colorectal cancer. Typical symptoms include bleeding during a bowel movement, fatigue, and weakness... read more Colorectal Cancer (such as ulcerative colitis Ulcerative Colitis Ulcerative colitis is a chronic inflammatory bowel disease in which the large intestine (colon) becomes inflamed and ulcerated (pitted or eroded), leading to flare-ups (bouts or attacks) of... read more ) would be advised to have a screening colonoscopy more often than is normal for people at average risk. If a woman has close relatives who have had breast cancer (family history Family history of breast cancer Breast cancer occurs when cells in the breast become abnormal and divide into more cells uncontrollably. Breast cancer usually starts in the glands that produce milk (lobules) or the tubes ... read more Family history of breast cancer ), screening for breast cancer with magnetic resonance imaging (MRI) in addition to mammography may be recommended.

Some screening measures are recommended for people with certain disorders. For example, people with diabetes should check their feet at least once a day for redness and ulcers, which, if ignored, may result in severe infection and ultimately amputation.


Preventive Medication Therapy

Preventive medication therapy (also known as chemoprevention) is the use of medications to prevent disease. For such therapy to be recommended, the person must be at risk of the disorder being prevented and be at low risk of side effects caused by the medication being considered.

Preventive medication therapy is clearly helpful in, for example, prevention of infection in people with certain disorders (such as AIDS), prevention of headache in people with migraines, and many other specific situations. Although preventive medication therapy is effective only in specific situations, some of those situations are common, so the therapy is useful for many people. For example, for adults at risk of coronary artery disease or stroke, aspirin is usually recommended. Newborns routinely receive eye drops to prevent gonococcal infection of the eyes. Women who are at high risk of breast cancer may benefit from preventive medication therapy (for example, with the medication tamoxifen).

Three Levels of Prevention

The three levels of prevention are primary, secondary, and tertiary.

In primary prevention, a disorder is actually prevented from developing.

Types of primary prevention include the following:

  • Vaccinations

  • Counseling to change high-risk behavior

  • Sometimes chemoprevention

In secondary prevention, disease is detected and treated early, often before symptoms are present, thus minimizing serious consequences.

Types of secondary prevention include the following:

  • Screening programs, such as mammography to detect breast cancer and dual x-ray absorptiometry (DXA) to detect osteoporosis.

  • Tracking down the sex partners of a person diagnosed with a sexually transmitted infection (contact tracing) and, if necessary, treating these people to minimize spread of the disease.

In tertiary prevention, an existing, usually chronic disease is managed to prevent complications or further damage.

Types of tertiary prevention include the following:

  • For people with diabetes: Control of blood sugar, excellent skin care, frequent examination of the feet, and frequent exercise to prevent heart and blood vessel disorders

  • For people who have had a stroke: Taking aspirin to prevent a second stroke from occurring

  • Providing supportive and rehabilitative services to prevent deterioration and maximize quality of life, such as rehabilitation from injuries, heart attack, or stroke

  • Preventing complications in people with disabilities, such as preventing pressure sores in those confined to bed.

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