Salt and hypertension have been linked in the public mind for decades. Over the past 50 years, hundreds of thousands of doctors have pounded on millions of patients to stop eating salt.
Yet growing evidence suggests that for people with normal blood pressure (and possibly even those with high blood pressure), reducing salt intake may not be the best strategy.
Not only do findings presented at a recent conference indicate this, but a new book by a leading cardiovascular research scientist warns that restricting salt can seriously harm our health in multiple ways.
This is what these scientists had to say. . .
Salt up – blood pressure down
A research team from Boston University School of Medicine enrolled a group of 2,632 people aged 30 to 64 with normal blood pressure readings at the start of the study. The researchers checked in with the participants every four years for 16 years, and recorded their salt intake.
The findings were that both upper (systolic) and lower (diastolic) readings increased as salt intake declined.
Do you feel the earth shaking under your feet? You should. Doctors have made “no salt” the eleventh Commandment.
Dr. Lynn Moore, associate professor of medicine, presented the findings at the Experimental Biology 2017 meeting in Chicago last April. She said, “It’s hard to tell whether higher sodium intakes are beneficial, but for generally healthy people, we saw no evidence of harm in consuming the average American intake of 3.6 grams a day.”
That’s well above the current guidelines of 2.3 grams a day (a teaspoon of salt) for people under 50 and a mere 1.5 grams a day for those older. The researchers found very little evidence to support these recommendations which, they say, “may be misguided.”
Their study demonstrated that eating foods rich in potassium, magnesium and calcium is more important in reducing blood pressure than focusing on salt.
Dr Moore continued, “Many people with high blood pressure are sensitive to salt, and for these people, lowering their salt intake will lower blood pressure,…however, the assumption that everyone should consume less sodium to lower their blood pressure is not supported by our study or previous studies.”
She also explained that a low-sodium diet can raise cholesterol and triglycerides (blood fats), have adverse effects on the kidneys leading to higherblood pressure, and could potentially increase the risk of heart disease.
It’s all a myth
Her findings are echoed strongly by Dr. James diNicolantonio, a scientist based at Saint Luke’s Mid America Heart Institute, Kansas City, Missouri. He serves as Associate Editor of the British Medical Journal’s Open Heart and is on the editorial advisory board of several other medical journals.
For his book The Salt Fix, published just a few weeks ago on June 6, he examined more than 500 medical papers. He found no solid evidence to support restricting salt; on the contrary, he found cutting back on salt to be detrimental.
The salt-blood pressure myth started over a century ago, but was perpetuated in the 1950s by New York scientist Lewis Dahl.
Since the blood pressure of rats was not increased by consuming salt, he engineered them over several generations to be salt sensitive.
When baby food with a high salt content was fed to the rats, it killed them. He then proclaimed that salt would be lethal to babies. This misinformation took hold and the myth came to be accepted that salt was harmful.
In reality, for four out of five people, blood pressure remains normal even with an increased salt intake. Even for those with hypertension, over half (55%) are exempt from salt’s effects on blood pressure.
If you have been diagnosed with high blood pressure, the prudent approach would be to cut back on salt for a couple of months and see if your blood pressure drops (it probably won’t, at least not due to salt). If you don’t have high blood pressure, you probably don’t have to worry about salt intake.
The Korean paradox
Dr. diNicolantonio points out that the Japanese, French and Koreans eat a high salt diet but have low rates of cardiovascular disease. The Koreans in particular consume 4.3 grams of sodium a day, on average, yet have some of the world’s lowest rates of hypertension; it’s called the Korean Paradox.
According to his research, a low salt intake can:
- cause obesity
- raise cholesterol
- elevate heart rate and risk of heart disease
- compromise the kidneys
- promote an underactive thyroid
- heighten insulin to raise diabetes risk
- reduce sex drive
- increase the risk of erectile dysfunction
- create feelings of fatigue
- cause dehydration
Even if blood pressure does increase with a higher salt intake, the author asserts it is offset by a reduced heart rate, lower insulin levels, better-balanced adrenal hormones and improved kidney function.
Dr. diNicolantonio states that an optimal sodium range for healthy adults, according to the research, is between 3 to 6 grams a day (about 1⅓ – 2 ⅔ teaspoons of salt).