Color of Urine Strips for Ketosis

Ketosis occurs when the body runs out of carbohydrates for energy. As a result, the body begins to process dietary and bodily fat to carry out necessary functions; the presence of ketones in urine thus indicates the metabolism of fat. Ketone testing strips evaluate the presence and concentration of ketones using a urine sample. Ketosis is evidenced by the a chemical reaction on the testing pad, which will change colors based on the concentration of ketones.

Presence of Ketones

The presence of ketones in urine may be surmised by a simple urinary test. Some test strips offer further evaluation of the presence of glucose, proteins or other material in urine. However, in testing for ketosis, strips need only to test for the presence of ketones.

Use of Test Strip

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Urinary ketone test strips (or reagent strips) are simple to use. The testing pad, on one end of the test strip, is exposed to urine; it can be passed through a urine stream or dipped into a urine specimen. The testing pad contains a chemical that reacts in the presence of ketones, changing color depending on concentration.

Ketone Readings

For utmost accuracy, ketone readings should be conducted exactly 15 seconds after exposure to urine. On the testing bottle will be a small selection of colored squares demonstrating (in ascending order) what colors the test pad will turn in the event that ketones are present.

Test Strip Readings

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Ketone test strips generally have five categories associated with ketone concentration in blood. A negative reading indicates no ketones are present in urine 1. Trace (5 mg/dL), small (15 mg/dL), moderate (40 mg/dL) and large (80 to 100-plus mg/dL) are the four positive ranges, indicated by a pale pink (trace) through deep burgundy (large) color on the test pad.


The testing pad may not necessarily accurately reflect the concentration of ketones in the urine. Various conditions--such as dehydration or dietary fluctuations--may alter the results of a urine reagent test. While ketosis is generally safe for a healthy individual, ketoacidosis may occur if ketones build up in a diabetic's system.