Sodium is an essential nutrient that plays key roles in nerve signaling, muscle contraction, and fluid balance. The average person living in the United States consumes approximately 3,400 milligrams of sodium per day in table salt, roughly 50 percent higher than recommended intake. Getting too much sodium can increase a person’s risk for high blood pressure, heart disease, and stroke. Findings from a new study suggest that lower salt intake increases blood levels of short-chain fatty acids in people with high blood pressure.
Short-chain fatty acids are fatty acids that contain fewer than six carbons in their chemical structure. They are produced by gut microbes during the fermentation of dietary fiber and reflect the overall health of the gut microbiome. Short-chain fatty acids play critical roles in many aspects of health, including the maintenance of healthy blood pressure.
The randomized, double-blind, placebo-controlled cross-over trial involved 145 men and women (average age, 50 years) with untreated high blood pressure. The participants were asked to limit their sodium intake to 2,000 milligrams per day for six weeks. During that time, the participants took either nine sodium tablets (providing 10 mmol sodium per tablet) or a placebo daily and then crossed over to receive the other tablets for another six weeks. The low-sodium diet plus the slow sodium tablets represented typical sodium intake, and the low-sodium diet plus the placebo represented a low-sodium intake. The authors of the study measure levels of short-chain fatty acids in the participants' blood and monitored their blood pressure.
They found that reducing sodium intake increased the levels of short-chain fatty acids in the participants' blood, and these increases were associated with reduced blood pressure and improvements in arterial compliance, especially among women. These findings suggest that lower salt intake can have beneficial effects on blood pressure and support public health recommendations for reducing salt intake.