POTASSIUM
Definition
Potassium is a mineral found in varying amount in most foods such as bananas, cashew nuts, spinach and lima beans.1 Within the body, potassium is an electrolyte that is critical for the normal functioning of the muscles and major organs, such as the heart, within the body. The level of potassium within the body may vary throughout the day and is dependent on a person’s dietary intake.2 Some population studies have found that persons eating a highly processed diet may become deficient in dietary potassium.3
The potassium test measures the total amount of potassium in the urine that has been excreted from the body at the time of the test. Research has shown that low levels of potassium can contribute to developing chronic diseases such as cardiovascular disease, diabetes and kidney disease.1,2
Population
Potassium results were obtained for persons aged 5 years and over, who agreed to participate in the National Health Measures Survey (NHMS) and provided a urine sample. Fasting was not required for this test.
Methodology
A spot urine sample was collected from participants and urinary potassium levels were measured at the Douglass Hanly Moir (DHM) laboratory.
There is no consensus of epidemiological cut off reference values for measuring potassium excretion from spot or estimated 24 hour urine collections, as such no cut off points have been defined in the NHMS.
Further information about the analysis method and machines used to measure potassium levels are available in Excel spreadsheet format in the Downloads page of this product.
Data items
The data items and related output categories for this topic are available in Excel spreadsheet format from the Downloads page of this product.
Interpretation
Points to be considered when interpreting data for this topic include the following:
- The urinary excretion of potassium varies significantly with dietary intake and there is no method to determine expected values based on a spot urine collection. It should be noted that other studies and research may have collected and measured 24 hour urine potassium excretion. The data from this topic should therefore be used with caution when comparing spot potassium excretion data with measured or estimated 24 hour urine potassium excretion data.
- There are a number of different test methods to measure potassium levels and each test method may produce different results. The data from this topic should therefore be used with caution when comparing potassium results from other studies using a different test method.
Comparability with other surveys
The NHMS is the first ABS survey to collect biomedical data on potassium levels.
Potassium data has been collected in other non-ABS surveys. However, caution must be taken when interpreting results due to the differences in scope, assay and instrument, and any thresholds applied in the final analysis.
ENDNOTES
1 WHO, 2012,
Guideline: Potassium intake for adults and children, Geneva, World Health Organisation.
http://www.who.int/nutrition/publications/guidelines/potassium_intake_printversion.pdf>, Last accessed 13/11/2013.
2 Gibson RS, 2005,
Principles of Nutritional Assessment, 2nd ed, New York: Oxford University Press.
3 Pan American Health Organization/ World Health Organization, 2010, 'Protocol for population level sodium determination in 24‐hour urine samples' ,WHO/PAHO Regional Expert Group for Cardiovascular Disease Prevention through Population-wide Dietary Salt Reduction, <
http://new.paho.org/hq/dmdocuments/2010/pahosaltprotocol.pdf>, Last accessed 14/04/2014.