Sicking to any diet is hard, but the high-fat keto diet is particularly challenging. That’s because it requires maintaining ketosis, or fat burning mode. Typically, you’ll need to eat less than 50 grams of carbs per day and ensure that 80 percent of your daily calories come from fat to maintain this state
If you’re going to eat bunless burgers, then you’ll want to be sure the payoff is worth the sacrifice. This can be done by measuring ketones, an acid made by the liver when your body burns fat. A higher level of ketones indicates you’re in ketosis.
Thankfully, there are at-home tests that make it easy to determine ketone levels. These are particularly helpful for those struggling to lose weight onthe diet. Small errors like eating too many blueberries can knock you out of ketosis, and regular testing can reveal whether it’s time to lower carb intake.
Not sure which method is right for you? These are your best options.
Urine Ketone Testing
First off, there are three different types of ketones: acetone, acetoacetate, and beta-hydroxybutyrate. Each ketone has a different method of testing, says Drew Manning, keto expert, personal trainer, and New York Times best-selling author.
Keto beginners should start with a urine-testing strip, the most common and affordable option that identifies acetoacetate in pee.
Global integrative nutrition health coach and keto expert Karissa Long explains to that your body creates an excess amount of ketones when it stops using glucose, or carbs, as energy. “These excess ketones are removed from the body via urine,” she says.
As a bonus, this method is easy: pee on the strip, wait for about 15-20 seconds, and the results will magically appear.
“The darker the result the more ketones that are in the urine,” Manning explains. There are usually guidelines on the package that explain how to use these strips, which can be purchased at almost any drug store.
After a while, your body becomes keto adaptive and fewer ketones are excreted in your urine, says Long. This means that you may be in ketosis but show low levels of urine ketones. However, a blood test would accurately reveal high blood ketones, so urine strips can be very deceiving, she says.
Blood Ketone Testing
This method to test beta-hydroxybutyrate ketones, found in the bloodstream, is your best bet, says Long.
“In my opinion, testing the blood for beta-hydroxybutyrate is the most accurate approach. You can buy a Blood Ketone Meter for around $25-60 with individual strips costing about $4 each,” she says.
To reach nutritional ketosis, your reading should be in the 0.5-3.0 mmol/l range. Don’t get discouraged if it takes a few weeks to hit this number as every body differs.
Testing at the same time each day provides a baseline for you to compare your progress, so try and test morning and evening at two specific times.
“Morning and night testing is recommended because ketone levels are normally lower in the morning and higher at night so you can get an idea of your ketosis range throughout the day,” she says.
Breath Ketone Testing
The last way to test is through the breath–and it’s pricey, but accurate.
“There are some good breath ketone monitors out there like LEVL, but they can be expensive up front” says Manning. Expect to pay around $400-$500 for one of these devices.
The benefit is you don’t have to prick any fingers or keep buying strips, but you’ll want to make sure you’re dedicated to keto first.
“They come with some pretty cool tracking technology via apps and Bluetooth, which makes it convenient,” says Manning. The apps can give you an idea of where your numbers are day-by-day or hour-by-hour with some pretty cool graphs.
You’ll want to look for a different reading in the breath compared to the blood, says Long.
“A zero or low value PPM (Parts per Million) means you are out of ketosis,” advises Long. You want to be between 8 and 40 PPM to make sure you’re within ketosis.
Not ready to spend shell out money on ketone tests? There are physical cues that your body is in ketosis, like bad breath and muscle cramps, but these are far less accurate.
This article originally appeared on Men’s Health