We are frequently asked questions about how to use the urine ketone test and especially how to interpret the data. Often the hue that is more or less purple can make us paranoid, which leads us to believe that we are out of ketosis. Even if it is not possible to establish strict rules, we try to explain and understand the best way to interpret the ketone test.
What Is the Keto Test?
The urine ketone test is the most widely used instrument for detecting ketosis due to its extreme practicality and low invasiveness. These are strips that must be immersed in urine, using the ability of the substance nitroprusside to respond to the presence of ketone bodies, acetoacetate. Depending on higher or lower concentrations in urine, Ketotest shows different colors, from darkest purple to pale pink.
But are we sure that a bigger color is better than pale pink? Let us try to explain the most common analyzes of urban legends.
If the Stripe Does Not Turn Purple, They Are Not in Ketosis: FALSE
Let’s be clear: the keto test is an indirect way of measuring ketosis. Technically, ketosis is determined by the presence of ketones in the bloodstream (ketonemia). Ketones in the urine (ketonuria) simply represent an overproduction of ketones, the excess of which can be found in the urine. So you may have ketosis, but the stick is barely tintable.
If I Drink More Water the Strip Becomes Less Colored: TRUE
The keto test only records relative concentrations, not the absolute number of ketone bodies. This means that changes in hydration state can affect the concentration of ketones found. When you drink a lot of water, the ketone levels in the urine tend to be diluted, resulting in a lighter color. However, this does not mean that you have a lower absolute level of ketone bodies in your blood.
Ketone Levels Do Not Vary Throughout the Day: FALSE
The concentration of ketone bodies can vary throughout the day due to varying hormone levels. Ketone levels are usually lowest in the morning and highest in the evening, peaking around midnight. Don’t obsess over this data, however, because the subjective component always plays a big role.
MCTs Can Color the Strips More: TRUE
Some people have higher levels of urinary ketones, especially medium-chain triglycerides (MCTs), after a high-fat diet. This may mean that dietary fat is converted into ketone bodies (helps reduce keto flu symptoms); For the same reason, this does not mean that body fat deposits are used for energy purposes. In other words, you increase exogenous ketosis.
If the Strip Is Darker I Am Burning More Fat: FALSE
Urinary ketone excretion can account for 10 to 20% of the total amount of ketones produced in the liver, which is about 10 to 20 grams per day. Since ketones have a caloric value of 4.5 kcal / g, the calorie loss in urine is only 45-90 kcal per day, which is irrelevant for losing body fat. Conversely, it appears empirically that higher urine ketone levels may indicate slower fat loss due to increased insulin production, which slows down the release of free fatty acids from fat cells.
Some Supplements and Medicines Can Falsify the Test: TRUE
N-acetylcysteine, a well-known antioxidant with mucolytic properties (known commercially as Fluimucil), can give false-positive results, as can some drugs, such as valproic acid, captopril, levodopa, and meat. In contrast, ascorbic acid (vitamin C) and nitrates can give false-negative results.
As Ketosis Progresses, I Should Find Darker Colors: FALSE
If ketones find a too dark color after keto adjustment, it may mean the kidneys are producing ammonia (which requires nitrogen) to balance the acidic properties of the ketones and prevent urine acidity. Therefore, increased ammonia (and ketone) excretion can mean protein loss. When the ketone concentration in the blood increases, the kidneys increase ketone absorption. If this increased uptake is accompanied by increased ketone excretion after keto-adaptation, additional nitrogen loss arises from ammonia production.
So What Color Should the Ketone Test Be?
The ideal situation seems to be one where we detect traces of ketones (light pink color) or one of the lowest ketosis levels in the gang, while also confirming that ketosis is present. This should indicate a blood ketone level that is not high enough to affect lipolysis or maintenance of muscle mass.