We often hear about “functional food.” But what does that mean? And how do high potassium foods fit in? Functional foods are those with health benefits beyond the basic nutrition they provide. The term is used a lot in marketing, but often the health benefit is not as definite as the advertisement claims. Among the most well established groups of functional food are the high potassium foods.
A number of studies show the reduction of hypertension, cardiovascular disease, osteoporosis and kidney stones in populations on a high potassium foods diet. Many epidemiological studies show populations on high potassium diets have less of these conditions. Multiple experimental human and animal studies show this improvement.
And there are multiple studies shedding light on the way these conditions improve. A great number of laboratory studies show the metabolic pathways that give these results. This is really the amount of work that needs to be done before considering a type of food as functional. One or two limited studies showing good results are not enough.
Food Component Versus Food
Many studies are based on the speculation that a single component of the diet is responsible for a particular favorable or unfavorable effect. One component strongly shown to be unfavorable is saturated fat. But a problem with studies showing harm is that they just result in recommending elimination of the food from your diet. What most people want to know is what they should eat. This is more important than what to avoid.
Only a small selection of food contains many of the food components that researchers study, such as resveratrol or each vitamin. Often when researchers separate the component from the food, the supplement does not give the anticipated effect. Many vitamins and antioxidants fall into this category. But that does not mean that the food component has no effect. There is a big difference between failing to show an effect and showing no effect.
Some Studies' Shortcomings
The researchers' suspicions are often based on good evidence, but the bench top procedures, or the procedures for data analysis, are not adequate to show the effect. For antioxidants, the ORAC test did not correlate with what was happening in the cell. It was not the right bench top procedure for what people want to know about these foods. So the conclusion should not be that antioxidants are useless. It should be that the jury is still out. We discussed this antioxidant problem in a prior post.
Metanalyses are a very popular way now to study data. Many of these studies fail to show the same effect for a food component that smaller studies showed. Metanalyses include methods and procedures to correct for the differences in the studies used in the metanalysis. But the failure to show an effect may be because the methods and procedures may not be the right ones. We discussed an interesting set of metanalyses here.
Cardiovascular disease is the leading cause of death globally. Many studies have attempted to find functional foods to reduce the amount of cardiovascular disease. High potassium foods are the major component of diets designed to reduce this disease. There are other factors to consider besides potassium. But none are more important than the potassium sodium ratio.
Just taking a supplement containing a large load of potassium does correct some aspects of cardiovascular disease. But there are other factors to also consider. By getting potassium from several food groups rather than from a pill of potassium salt, you take care of those other factors. In upcoming posts we will discuss the functional food considerations of high potassium foods. And we will consider what else each of the high potassium food groups can provide beyond the favorable effect of potassium.
The “Links to Food Potassium Tables” on the tab at the top of the page has links to all the tables of nutrient and potassium values on this site.