From these results, the researchers from Tel Aviv University argued that an increase in dietary potassium consumption is a previously unrecognized predictor of BMI reduction in a weight-loss oriented intervention.
“It is notable that the increase in dietary potassium was a stronger predictor of weight loss in this study than such well-established factors as a reduction in sugar consumption and in overall caloric intake,” they wrote in their report, published yesterday in the journal Nutrients.
As the link between potassium intake and weight loss is still novel, the researchers said that “prospective trials in which dietary potassium content is set a priori at low versus high levels will be needed to determine whether or not an increase in dietary potassium intake can be used to improve weight outcome.”
The findings may affect how weight loss clinical trials or diet programs to tackle obesity and metabolic syndrome account for potassium content.
In an attempt to lose weight, many individuals focus on reducing carbohydrate, fat, and caloric intake. “Less attention has been given to the possibility that other dietary components could be related to the achieved reduction in BMI during caloric restriction,” they argued.
The link between increased potassium intake and an above-average decrease in BMI came through a post-hoc analysis of nutritional data from an ongoing study, in which participants with metabolic syndrome (a suite of metabolic abnormalities associated with the development of cardiovascular disease and type 2 diabetes) go through an intensive year-long intervention.
Sixty-eight participants with a mean age of 51 years follow a nutritional recommendation based on the low calorie, high protein Mediterranean diet.
One reason why the researchers focused on potassium intake was because two widely recommended diets entail an increase in the consumption of potassium, they wrote, namely the Mediterranean diet and the DASH (Dietary Approaches to Stop Hypertension) diet.
“In one study of the Mediterranean diet, better compliance with the diet was linked to higher consumption of dietary potassium as well as calcium and magnesium,” they wrote.
While many reports have focused on how potassium intake is linked to blood pressure reduction when individuals follow the Mediterranean or DASH diets, “the potential role of potassium intake in weight loss has thus far generated little interest.”
To assure compliance in the present study, participants had a weekly meeting with a dietitian for the first three months, every other week during months four to six, once a month during months seven to nine, and every six weeks during the last three months of the study.
Data from the current report came from participants who have completed the full year of intervention, which also included a guide for physical activity in addition to the diet plan. Lipid and blood pressure lowering drugs were still used throughout the ongoing study.
Confirming previous studies
Though the body of science around potassium and obesity is still scarce, the researchers wrote that their results agree with some previous studies.
“In three different reports from Korea and Japan, there appeared to be a trend for lower prevalence of obesity or metabolic syndrome with higher consumption of potassium,” they wrote, citing study published in Atherosclerosis in 2013, PLoS ONE in 2013, and British Journal of Nutrition in 2015.
“The mechanisms through which higher dietary potassium may facilitate weight loss remain elusive,” the Tel Aviv researchers added. “Putative effects might involve a reduction in inflammation and improvement in insulin sensitivity, subtle effects on serum potassium which modulate energy balance or neural routes which depend on gut sensing of potassium with beneficial effects on fat deposition/mobilization or energy balance.”