In general, the more sodium in an individual’s diet, the higher an individual’s blood
pressure is. One such study, the Trials of Hypertension Prevention (TOHP), showed
a linear 17% increase in cardiovascular disease risk per 1000 mg per day increase
in sodium from levels starting at 1,500 mg per day. The average of 3,500-4,000
mg of sodium a day in the typical American’s diet far exceeds the American Heart
Association (AHA) recommendation of a limit of 2,400 mg (5.8 gm salt), or even
better a 1,500 mg of sodium (3.6 gm salt) per day for everyone including children.
There is considerable individual variation in if and how much salt increases blood
pressure. Some people are “salt resistant,” the sodium content of their diet has little
or no effect on their blood pressure. Some research suggests that very low sodium
consumption will increase the risks of death from CVDs and all causes, but most
research supports the current recommendations to limit sodium.
The Institute of Medicine (IOM) examined research on dietary sodium intake and
health outcomes in the general U.S. population and among individuals with hypertension;
prehypertension; those 51 years of age and older; Black Americans; and
those with diabetes, chronic kidney disease, and congestive heart failure. The 2013
report from the Institute of Medicine concluded that existing evidence suggests
• Consuming more than 2300 mg of sodium a day increases the risk of high
• There is not enough evidence to say that eating less than 2,300 mg of sodium
a day benefits cardiovascular disease outcomes for the general population.
• In people with known cardiovascular disease, diabetes, or chronic kidney
disease, there is some evidence that a diet of 1,500 to 2,300 mg of sodium a
day may have negative health effects compared with higher-sodium diets.
However, this evidence is not strong enough to say that these individuals
Since the release of the report, a study among individuals with chronic kidney disease
(about 11% of U.S. population) suggests that reductions in sodium intake to
the 2,300 mg/day level would have considerable benefit in preventing heart failure,
myocardial infarction, and stroke.
The IOM report led to confusing news reports with headlines like “Doubts About
Restricting Salt” and “Study finds Low-Salt Diet Poses Health Hazard” that inaccurately
suggest there is no health benefit from decreasing salt intake. Because most
Americans consume far more than 2300 mg of sodium a day, a decrease in sodium
intake to an average of 2,300 mg per day would be beneficial to most people. Some
observers would say that there is not enough evidence that further decreasing sodium
intake to 1500 mg a day has additional benefit for the prevention of cardiovascular
disease—or is harmful. However, a very careful analysis published
in the New England Journal of Medicine in 2016 concluded that there is strong
evidence that there is a strong linear dose-response effect of sodium reduction on
blood pressure and CVD risk down to 1,000 mg/day.
Because salt is added to so many processed foods, including canned foods, bakery
goods, soups, snack foods such as chips, and fast foods such as pizza, it is difficult
to limit intake of sodium. As a result, 90% of Americans exceed the 2,400 mg/day recommendation. Note that 1 gram (gm) of table salt contains 413.19 milligrams (mg) of sodium.
According to the AHA, reducing daily sodium intake to less than
1,500 mg per day is particularly important for persons who are age 51 and older and
those of any age who are Black or have hypertension, diabetes, or chronic kidney
disease. The 1,500 mg recommendation applies to about half of the U.S. population,
including children, and the majority of adults.
For most people, there is little need to worry about not getting enough sodium.
Even in the probably unlikely instance that it did turn out to be harmful, the CDC
estimates that fewer than 1% of Americans reach the 1,500 mg daily limit—our
food supply is just too loaded with sodium. In fact, one large international study of
17 countries found that, as measured by sodium excretion, only 4% of study subjects
ingested sodium in the U.S. recommended ranges. Only 3.3% of those studied
consumed sodium as low as 2,300 mg per day, and just 0.6% of those studied
reached 1,500 mg per day.
A low sodium diet is even more effective in lowering blood pressure when it is combined
with measures to increase fitness through appropriate levels of physical activity, attaining and maintaining a healthy weight and managing stress. Alcohol and cigarettes also contribute to hypertension. More than one drink of alcohol a day
can raise blood pressure, and the chemicals in cigarette smoke raise blood pressure
and damage blood vessels.
This blog presents opinions and ideas and is intended to provide helpful general information. I am not engaged in rendering advice or services to the individual reader. The ideas, procedures and suggestions in that are presented are not in any way a substitute for the advice and care of the reader’s own physician or other medical professional based on the reader’s own individual conditions, symptoms or concerns. If the reader needs personal medical, health, dietary, exercise or other assistance or advice the reader should consult a physician and/or other qualified health professionals. The author specifically disclaims all responsibility for any injury, damage or loss that the reader may incur as a direct or indirect consequence of following any directions or suggestions given in this blog or participating in any programs described in this blog or in the book, The Building Blocks of Health––How to Optimize Your Health with a Lifestyle Checklist (available in print or downloaded at Amazon, Apple, Barnes and Noble and elsewhere). Copyright 2021 by J. Joseph Speidel