Salt, or sodium chloride, is our current dietary Darth Vader, excoriated soundly by many as causing almost all the high blood pressure so common in our society, traffic woes aside. And as we all know, uncontrolled high blood pressure is a major underlying issue when it comes to heart attacks and strokes. In this week's podcast I call sodium the villain of the decade, and now a study in Archives of Internal Medicine may have identified its Luke Skywalker: potassium.
The study looked at data from a very large, ongoing series of studies known as 'NHANES.' That stands for National Health and Nutrition Examination Survey. The third of these surveys reported on here assessed diet and many other variables among over 12,000 US adults in a nationally representative sample from 1988-2006. As part of dietary data crunching, estimates of sodium and potassium consumption were calculated. The study found that when the population was divided into quarters, those who consumed the lowest amounts of potassium along with the highest amounts of sodium had almost a fifty percent increased risk of death and cardiovascular disease compared with those who consumed the inverse of high potassium and low sodium. The risk remained the same regardless of race, years of education, body mass index, physical activity, sex, or whether high blood pressure was present.
As Rick points out in the podcast, when people consume more potassium they tend to consume less sodium, so clearly, increasing potassium consumption seems like the thing to do. He also says, however, that supplements are not recommended. Rather, foods that contain higher amounts of potassium should be chosen in lieu of those with a lot of sodium, including fresh veggies and fruits, and avoidance of canned and processed plant foods, which almost always are manufactured with large amounts of sodium chloride. In fact, the vast majority of sodium consumed by Americans is that found in processed foods, not added via a salt shaker at the table.
I point out in the podcast that the federal government has already stepped into this fray with new food manufacturing guidelines regarding sodium addition to be phased in over time. It's also my personal experience that as I've decreased my own addition of salt to my food, I miss it less and am more sensitive to smaller amounts. As a salt addict, I encourage all who are considering such measures that it can be done!
Rick also recalls that we have discussed in a recent podcast at least one study offering the contrary conclusion that sodium is not the villain much of research concludes it is. Our primary criticism of that study was the subjects: young men, who might be expected to experience little if any high blood pressure, even with a lot of salt consumption. We do feel confident that some groups of people really are disproportionately sensitive to sodium, including many African Americans, and we are generally in support of efforts to reduce sodium as much as practical.
Other topics this week include maternal smoking and birth defects in Human Reproduction Update, placebos and asthma treatment in NEJM, and changing family cancer histories and screening in JAMA. Until next week, y'all live well.