How to Control Your Blood Pressure: The Truth About Salt

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Hypertension. It’s been called “the biggest killer in the American diet.” Also known as high blood pressure, hypertension affects one in three adults in the United States. Even more alarming, it’s showing up in more and more children. Often called a silent killer, the condition may be asymptomatic while quietly raising the risk for potentially deadly disorders like kidney disease, stroke and heart disease.  So, how do you control your blood pressure?

Most Americans consume too much salt, an indulgence linked with runaway rates of hypertension. And the simple solution is eating less salt.

Most experts recommend this approach because it makes sense from a plumbing perspective. Excess sodium draws water into your bloodstream. This increases both blood volume and pressure on blood vessel walls.

The problem is, studies linking reduced salt intake with lower blood pressure have been inconsistent. Moreover, recent research has thrown conventional wisdom about dietary sodium into question. A number of studies indicate that people react differently to excess salt. Current findings also suggest that existing guidelines may be too restrictive for healthy people and that the so-called Standard American Diet may be the heart of the problem.

Here are some takeaways from that research that may help you to assess whether you are consuming too much salt.

Everyone Isn’t Sensitive to Salt

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Birth size impacts your ability to process sodium. Low birth weight has been linked with a higher incidence of hypertension later in life. One study found that elderly people who weighed less than 6.7 pounds at birth were more likely to be salt-sensitive and to suffer from hypertension.

When fetal growth is restricted because the mother is undernourished, developing organs such as the kidneys, liver and pancreas may be affected, altering the baby’s metabolism. Children born with a low birth weight who gain weight rapidly between the ages of three and fifteen are particularly vulnerable to developing hypertension as they age.

Sodium Is an Essential Nutrient

As an electrolyte, sodium supports numerous bodily functions, especially those that keep you hydrated. Studies have not been able to connect current recommendations (slightly less than a teaspoonful of salt daily) with positive health outcomes.

One analysis concluded that not getting enough sodium (less than 3 grams a day) may be as risky as getting too much (more than 7 grams.) Sodium deficiency can actually raise the risk of developing heart disease. These researchers concluded there is no value to reducing sodium intake unless you already suffer from high blood pressure and consume too much salt.

Other Nutrients Balance the Effects of Sodium

Some research indicates that when sodium is consumed along with high amounts of magnesium, calcium, and especially potassium, lower blood pressure levels likely result. It’s worth noting that ultra-processed foods are notoriously high in sodium and sadly lacking in magnesium, calcium, and potassium.

Processed Foods Linked with Hypertension

Black Americans are more likely to develop hypertension than their white counterparts. A recent study that looked at more than 30,000 people found that a diet high in fried and processed foods and sugar-sweetened beverages played a key role in Black Americans’ increased risk of developing hypertension. 

Whole Foods Diet Supports Healthy Blood Pressure Levels

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A number of dietary patterns, including the Nordic and Portfolio diets, have been linked with healthy blood pressure levels. The DASH (Dietary Approaches to Stop Hypertension) diet is probably the most studied: It has been shown to lower blood pressure levels within two weeks, Like other effective diets, it outlaws nutrient-deficient processed foods (high in salt, sugar and unhealthy fats) and prescribes nutritious whole foods (high in fiber and rich in micronutrients like potassium, calcium and magnesium.) 

While the DASH diet initially focused on improving and reversing hypertension, subsequent studies have shown that if followed over the long term, it can have multiple health benefits. It promotes weight loss (a risk factor for hypertension) and reduces the risk of stroke, heart failure, osteoporosis, kidney stones and some types of cancer.

A key message from current research is that when it comes to hypertension, salt may not be guilty as charged. It’s more likely that the major perpetrator is a high intake of ultra-processed foods, which are deficient in nutrients that can keep hypertension in check.

Potassium balances sodium in the blood while relaxing blood vessel walls and it is a well-known warrior against hypertension. Magnesium and calcium have strong supporting roles in this disease-fighting brigade. Other nutrients provided by whole foods like antioxidants, fiber, and healthy fats work together to help keep blood pressure in line.

Most Americans get far fewer of these nutrients than they need, even though potassium, in particular, is plentiful in many whole foods. But the research is clear: If you already suffer from high blood pressure, eating a nutritious diet known to combat hypertension can help to lower those troublesome levels. And if you don’t have high blood pressure, it can help you to keep the condition at bay.  


About the Author

Judith Finlayson is the author of You Are What Your Grandparents Ate:  What You Need to Know About Nutrition, Experience, Epigenetics, and the Origins of Chronic Disease. Visit her at www.judithfinlayson.com.

 


How to Control Your Blood Pressure — Sources

JAMA 2018.
The Lancet 2018
FASEB Journal 2017.
The American Journal of Clinical Nutrition 2010.