Failure of preventive medicine is the cause of great human misery.
      Preventive medicine is widely applicable, relatively easy, and much more affordable than individual treatments, which tend to be complicated, often unaffordable, and frequently limited to the privileged few.  The vernacular wisdom that a bit of prevention is worth a lot of treatment is even truer today because industrialization and population growth are relentlessly polluting our tiny planet.
      Sanitation (clean water and sewage control) is the most essential form of prevention but, unfortunately, it is currently lacking for the majority of earth’s population.  Preventable infectious diseases such as Malaria, Tuberculosis, Bilharzia, Aids, Diarrhea, etc. kill more per year than all our wars combined.  Malnutrition is still a major threat to population health and so is illiteracy and, although both are preventable, they continue to be widely prevalent in spite of technological progress.
      As for enlightened individuals living in more affluent microcosms, there are other preventable diseases that are commonly neglected even though they are readily detectable with annual physical examinations:
      1.  High Blood Pressure is a silent killer because it causes no symptoms.  When untreated, it is the commonest cause of strokes and heart failure; moreover, it increases the incidence of heart attacks, ruptured aneurisms, and renal failure.  It can only be detected by measurement and the best measurements are those performed at home by the vigilant individual because they avoid the common pitfalls of White Coat Hypertension (i.e. doctor’s office) hypertension.  If the average of many home-blood-pressure measurements is >130/80, this is considered pre-hypertension and requires treatment before it gets worse and more difficult to control.  Home blood-pressure monitors are widely available and quite reliable.  Declining treatment because the individual feels well is the commonest argument used by those who are not medically enlightened.  Reducing salt intake and walking an hour a day may be all that is needed when pre-hypertension (BP>130/80 and <140/90) is first diagnosed.  Beyond that point, medications are usually required.
      2.  Obesity and overweight have reached epidemic proportions especially in affluent societies.  Although treatments abound, there are no long-term effective medications that have stood the test of time and science.  Overweight causes a progressive increase in many diseases such as cancer, diabetes, high blood pressure, high cholesterol, high triglycerides, sleep apnea, heart failure, back, knee, and hip arthritis, frequent falls, poor surgical outcomes, and slower recovery from myriad illnesses and infections.  Prevention rests on Cognitive Behavior Therapy, which teaches the individual to exercise daily and to think and prepare his mind before engaging in any form of eating.  Unfortunately, success depends on the individual’s abilities to learn new, life-altering ways.
      3.  Diabetes (fasting blood sugar >125mg/dl) begins as pre-diabetes (fasting blood sugar 100-125mg/dl).  During this early stage, it is entirely preventable with exercise and weight loss.  If the individual will just walk one hour a day and reduce his weight, his pre-diabetes may never progress to diabetes.  Exercise and weight reduction reverse insulin resistance, which is the most important metabolic derangement in early diabetes.  Preventing diabetes also prevents all its well-known complications such as blindness, gangrene of digits, and renal failure.
      4.  Hyperlipidemias (high cholesterol & triglycerides) are major causes of heart attacks, strokes, and poor blood supply to the vital organs and extremities.  They, like high blood pressure, cause no symptoms and are not detectable without blood tests.  Cholesterol lowering medications are safe and very effective in preventing the many types of vascular obstructions caused by hyperlipidemia.  Resistance to treatment is based on irrational fears of medicines.  There is clear scientific evidence that medical treatment saves, prolongs, and improves the quality of life and has no long-term side effects.  In spite of that, medical therapy is often resisted by those who can easily afford it.  Such fears of medicines are major obstacles against disease prevention.
      5.  Prostate cancer becomes common after age 50.  Most cases are detectable at an early stage by physical examination of the prostate and the PSA (Prostate Specific Antigen) blood test.  The science of prostate cancer is still in evolution and, consequently, it is not yet known which form of treatment gives the best results.  Moreover, prostate microscopy (pathology) is not always capable of telling us which cancers will be aggressive and which will be passive.  This presents another therapeutic problem because the passive cancers may be compatible with a normal life span and may not require treatment.  It is well known that as men age, more and more of them will harbor small prostate cancers that may not affect the longevity or quality of their lives.  Until more scientific studies are completed, opinion will remain divided about what constitutes the best treatment approach.
      6.  Colon cancer, a major killer after age 50, is 90% preventable with colonoscopy.  It tends to begin in polyps and it takes an individual polyp 5-10 years to become cancerous.  Colonoscopy at age 50, if it finds polyps, classifies the individual as a polyp maker, excises the polyps, and places the individual under appropriate surveillance.  Smokers, individuals with family history of colon cancers, obese individuals, and sedentary individuals are at an increased risk of developing colon cancers.  All those who can afford a colonoscopy should have it done when they turn fifty.
      7.  Ovarian cancer is another major killer but, unfortunately, remains undetectable in its early stages.  Pelvic examination, pelvic ultrasound, pap smears, and the CEA blood test do not find it early enough to save lives.  The CEA blood test is especially inadequate because it has too many false positives and false negatives and should not be utilized as a routine screening test because it causes confusion and worry.  Even surgical removal of the ovaries does not totally prevent ovarian cancer.  Unless a test is developed that can detect ovarian cancer in its early stages, this disease will remain largely unpreventable.
      8.  Breast cancer is relatively preventable with mammography but mainly between the ages of 50 and 75.  We are not sure that mammography done between the ages of 40 and 50 or after 75 saves enough lives to make it mandatory.  Breast self examination, which is how many cancers are discovered, often finds them too late.  The mammography age rules may not apply to women with a strong family history of breast cancer.  Certain blood tests that detect such breast cancer genes may guide such women to have their breasts removed as a preventive measure, even though such surgery may not give perfect results.
      9.  Cervical cancer is readily preventable with Pap smears that are done during pelvic examinations.  It is a sexually transmitted disease caused by certain strains of the HP virus.  A Pap smear is not necessary in women who have never had sex or in those who have had an elective hysterectomy (surgical removal of the uterus) because they no longer have a cervix.  However, women who have had a hysterectomy because of a cervical malignancy will still need to have Pap smears.
      10.  Lung cancer is common in smokers and is seldom detected at the stage when it is curable.  Chest x-rays, which were thought to be sensitive detectors, have proven inadequate and useless.  Scientific studies have shown that doing annual chest x-rays on smokers does not detect lung cancers early enough to save or prolong lives and seems to do more harm than good.  Hence, a chest x-ray should only be done for symptoms and not for prevention.  Other more sensitive tests such as CT scans are under study but the results are not out yet.  At present, the most important preventive measure against lung cancer is to stop smoking.  Stopping smoking also reduces cancers of the mouth, larynx, esophagus, stomach, kidneys, and urinary bladder.  Moreover, it also reduces the incidence of heart attacks, strokes, aneurisms, pneumonias, asthma, and progressive lung damage.
      11.  Osteoporosis, the leading cause of vertebral, hip, and other arm-and-leg fractures is easily preventable.  In women it begins after menopause and in men, after age 65.  Vitamin D deficiency is a common cause and so is sedentary life (i.e. not taking daily walks) and inadequate intake of calcium.  A bone density is diagnostic and therapy is quite effective.  An adequate intake of calcium (1200 mg/day), vitamin D (1000 u/day), and daily one-hour walks are essential for those at risk.  Specific medications are available that can reverse osteoporosis but their use in the pre-osteoporosis stage (i.e. osteopenia) has not been shown to reduce fractures and is not universally recommended.

      12.  Vaccines have great preventive powers and all modern vaccines are safe, effective, and should be given as recommended to both children and adults.  There are no scientifically rational arguments against vaccines and those who refuse them do so because of imaginary fears.  The one annual vaccine that everyone should take is Influenza because epidemics occur annually and cause a pronounced rise in mortality and morbidity worldwide.  The myth that the Influenza vaccine can cause Influenza is unfounded because the vaccine does not contain any living virus.  Patients who say that every time they are vaccinated they get influenza should be informed that the vaccine takes 3-4 weeks to become effective and that, during this vulnerable period, they may actually succumb to other viral illnesses including Influenza.  Moreover, many patients think that every viral infection is the flu.  In fact, the flu only refers to Influenza, which is a severe illness marked by very high fever, severe chills, severe body aches, and a slow, protracted recovery.  Most patients who assume that they have had the flu will have actually had one of the lesser, seasonal respiratory viral infections.  On the other hand, patients who have had the real flu (i.e. Influenza), never forget their horrible experience as long as they live.
      To conclude, while medical treatments help individuals, preventive treatments save millions of lives and are epidemiologically crucial for the health of nations.  Like unhealthy individuals, unhealthy nations slowly die, and history abounds with such examples.  Moreover, with modern advances in technology, global health has become inseparable from national health and, therefore, if we allow entire nations to succumb to preventable diseases, planet earth will be our next victim.  Sir Winston Chruchill was right when he said, "Healthy citizens are the greatest asset any country can have."