Tuesday, 25 April 2017

How Much Salt Are We Supposed to Eat?


Salt is tasty, but is it good or bad for us?
Public domain photo by hansbenn

Nutritionists and health practitioners have been telling us for many years to limit our salt (sodium chloride) intake. One reason for this recommendation is to reduce the chance of high blood pressure, or hypertension. High blood pressure can in turn increase the chance of a stroke, heart disease, and a heart attack. Now the results of a study of sodium intake and blood pressure are calling into doubt the benefit of the reduced salt recommendation. The results were announced in April 2017 in the Experimental Biology meeting in Chicago.


The Research


The study was performed by the Boston University School of Medicine and was called the Framingham Offspring Study. It involved 2,632 people aged 30 to 64 and lasted for 16 years. The participants all had normal blood pressure at the start of the study. The researchers found that consuming less sodium wasn't linked to a lower blood pressure. In fact, they found that people eating less than 2,500 milligrams of sodium a day had a higher blood pressure than those who ate more sodium. The researchers also stated that other large studies in the past have discovered that both people with low sodium intake and those with a very high intake have an increased risk of heart disease.

The researchers say that the current recommendation for a low sodium intake may be "misguided". Their study suggests that most people with an average sodium intake - 3,400 mg a day according to the American Heart Association - don't need to worry about sodium and actually have the lowest risk of heart disease. One of the researchers does say that there is "likely a subset of people sensitive to salt who would benefit from lowering sodium intake", however.


Heart Association Recommendations


A representative of the heart association disagrees that their recommendations for sodium intake are misguided and has criticized the protocol followed by the new study. This study says that less than 2,500 milligrams of sodium a day is unhealthy; the American Heart Association says that more than 2,300 milligrams a day is unhealthy and that 1,500 mg a day is a better goal for most adults. Clearly we have a problem.


Should a salt shaker be on the table?
Public domain photo by Ben_Kerckx

Other Important Minerals

As is often the case, it's hard for the average person to decide what to do when the experts can't agree. There may be a way out of this conundrum, however. An interesting discovery in the recent study was that people who had higher intakes of potassium, magnesium, and calcium as well as an average intake of sodium had lower blood pressure. The lowest blood pressure of all was found in people who ate 3211 mg of potassium a day and 3717 mg of sodium a day - an amount of sodium that the heart association considers dangerous.

Many nutritionists say that it's important to eat enough potassium and magnesium, so that's a goal that I'm aiming for. The minerals are abundant in green, leafy vegetables. Since nutritionists seem to agree that green vegetables are healthy foods in many ways, I'm going to try to keep my intake high.

As far as the sodium level in foods is concerned, I'm still going to avoid foods with a very large amount of added salt, such as some varieties of prepared soups and some canned vegetables and meats. I don't feel comfortable about deliberately eating salty foods when the topic is controversial amongst health researchers. Other than reducing the foods with the highest salt content, I'm not going to worry too much about sodium, though, as long as I keep eating vegetables. I hope the experts soon reach a consensus about what we should do with respect to our salt intake, as long as this consensus is good for our health.


References



Low sodium diet and blood pressure from Science Daily
A high sodium diet from the San Diego Tribune