Does your age make any difference as to whether you should cut back on sodium? A study published yesterday in the journal JAMA Internal Medicine looked at the effects of three different sodium levels among more than 2,600 people ages 71-80. The three levels were 1) less than 1,500 mg, 2) 1,500-2,300 mg, and 3) more than 2,300 mg.
In the 10 years that the study participants were followed, the death rate was lowest (30.7 percent) for those who ate 1,500 to 2,300 mg sodium per day. People who ate around 1,500 mg a day had a death rate of 33.8 percent. People who ate more than 2,300 mg/day had the highest death rate - 35.2 percent. However, the researchers said that the findings were not statistically significant, which means they could have resulted by chance. A conclusion of the study was that sodium intake did not affect death, heart disease, or heart failure over the 10 years researchers followed the participants.
For reference, the American Heart Association and American College of Cardiology guidelines for prevention of cardiovascular risk state that reduction of sodium down to 1,500 mg/day can result in greater reduction in blood pressure (a major risk factor for heart disease and death) than higher levels.
The American Heart Association examined the new study and found several limitations (discussed in a blog post by the association's president). Ultimately, there is nothing in the new study that will cause the association to change its sodium recommendations.
Here are a few other points from the study:
- The study wasn’t designed to identify a goal number for how much sodium to eat. On average, Americans are eating more than 3,400 mg sodium/day. We should focus on reducing from this high level (especially when the levels compared in the study are so much lower than what we’re eating now!).
- The group eating 1,500 mg of sodium a day was also eating considerably fewer calories and was more likely to be taking medications than the other groups. This means that they may have had worse results because of other health problems they had, not because of the amount of sodium they ate.
- The study participants were Caucasian and African-American adults ages 71-80, so the results may not apply to people of other ages or races.
- The people in the study were considered relatively healthy, so they might not be representative of others who would fall into the same population group but might have existing heart disease or be at higher risk for it. Almost half of the nearly 86 million American adults who have some form of cardiovascular disease are older than age 60. And two-thirds of people age 60 and older have high blood pressure, which is a major risk factor for heart disease.
- An important limitation of the study is that the participants' sodium intakes were estimated based on a questionnaire they filled out about their eating habits. This is not as accurate as using multiple days’ worth of urine samples.
As always, it’s important to keep the big picture of a healthy diet in mind. Sodium reduction is one component of an overall heart-healthy eating pattern that emphasizes intake of vegetables, fruits, and whole grains; includes low-fat dairy products, poultry, fish, legumes (like black beans, kidney beans, etc.), non-tropical vegetable oils (like olive and canola), and nuts; and limits intake of sweets, sugar-sweetened beverages, and red meats. This week, the World Health Organization urged action on its goal of reducing the population's salt intake by 30 percent as part of its goals to reduce premature death from illnesses like heart disease. Read our article on reducing sodium to get tips for cutting back.
Have you taken the pledge to reduce the sodium you eat?