Many people assume that if they have not been diagnosed with hypertension by the time they are 65 years old, they are out of the woods. Not so, according to a new study. Americans in their 50s, 60s and 70s who still have normal blood pressure should not feel very confident that hypertension is not in their future. What do we know so far? Earlier studies have shown that about 70% of all women age 65-75 have already developed hypertension, and by age 65 almost 80% of black women in the US have hypertension.1

New study shows 90% of Americans destined to develop hypertensionA recent study examined the residual lifetime risk of developing hypertension in men and women with normal blood pressure at age 55 or 65. Table 1 below shows the results of this new study.2 Consider these statistics:• For people whose blood pressure is still within the normal range at age 55, over half will develop hypertension in the next 10 years and over 90% will develop hypertension in the next 25 years.• For those lucky enough to make it to age 65 without being diagnosed with hypertension, about two in every three will develop hypertension within the next 10 years.This data should serve as a wake-up call to many older Americans who have become complacent about their chances of developing hypertension. What is the source of this false complacency?Much of the confusion about the lifetime risk of developing hypertension can be traced to distorted information from the Salt Institute. The Salt Institute has claimed for many years that only about 20 to 25% of Americans have hypertension. This is true in a narrow sense, but very misleading since most of those without it today will eventually develop it.They also claim that people do not need to avoid salt unless they already have hypertension and are also "salt-sensitive.” They maintain that most people with hypertension are not "salt-sensitive." This implies that about 90% of Americans have nothing to worry about when it comes to dietary salt. This is false.The simple truth is that in every human population studied in which little or no salt was added to their diet, there was a virtual absence of hypertension.3 By contrast, in every human population group ever studied in which salt is customarily added to the diet, hypertension is common. Wherever salt is added to the diet, most people develop hypertension by the time they reach their 60th birthday.4The rise in blood pressure with age in the US and all other modern societies led most doctors to believe that this was a normal part of the aging process. For many years doctors told their patients that a systolic blood pressure of up to 100 plus one's age was "normal." By contrast, most doctors always suspected that cigarette smoking caused most lung cancer and emphysema because these illnesses were far less common in their non-smoking versus smoking patients. However, nearly all Americans consume far too much salt. This means that doctors in the U.S. never see patients who don’t consume excessive salt. Further, the few doctors that did travel to far away lands were so struck by the absence of hypertension in older people where salt was not used that they came to believe that salt must be the primary causal agent causing hypertension.5 The bottom lineThe more added salt from the saltshaker or processed foods is reduced in the diet the healthier Americans will become. Excessive dietary salt has been linked to hypertension, strokes, heart attacks and kidney failure but also to stomach, esophageal and kidney cancer. Osteoporosis, kidney stones, and headaches have also been tied in part to excessive dietary salt. The DASH-2 study proved that reducing sodium to 1500 mg per day reduced blood pressure more than reducing it to only 2400 mg in both normal and hypertensive subjects. The good news is that dramatically reducing salt intake will slow, stop or often reverse the cellular damage leading to these all too common health problems. The reduction in disease risk for those who cut out all salty foods can be as dramatic as the reduced risk of lung cancer, emphysema and heart disease in people who quit smoking.For more detailed information and CPE courses on salt intake, visit us online at www.foodandhealth.com.By James J. Kenney, PhD, RD, LD, FACNReferences:1. Harvard Women's Health Watch. 1996;III:2-32. JAMA 2002;287:1003-103. Hypertension 1985;7:628-374. Am J Clin Nutr 1979;32(suppl):2659-625. The Hague: Martinus Nijhoff 1980:489-508