If you’ve looked into keto online you’ve probably seen people testing ketones either with urine strips or a blood monitor. Is this necessary? Typically I’d say no. I always just urge people to eat whole foods and low carb and not worry about ketones. It is not necessary to be in ketosis all the time – cycling in and out of ketosis is good for metabolic flexibility. I know that some people like to have that reassurance of seeing the colour or the number. It can become obsessive (and hella expensive!)
There are 3 ways to test for ketones: breath, urine, and blood. There are 3 types of ketones: acetone (released in your breath), acetoacetate (released in the urine), and b-hydroxybutyrate (in your blood). So you can get a breath monitor, urine strips, and a blood monitor. The breath monitor is not the most accurate. The urine strips are accurate until your body starts to effectively use ketones, at which point you’ll no longer be peeing them out. The most effective way to test is the blood monitor. Similar to a diabetic testing glucose you prick a finger and use the device to measure ketones in the blood. However the device can cost $30-50 and each strip can cost $3-5! So daily testing adds up!
After over a year of eating ketogenic (not in ketosis all the time but most of the time) I decided to get a blood monitor to see where I was at. I was coming at this from a place of intrigue – how does fasting affect my levels? What about exercise? How do I feel when I’m sure I’m in ketosis?
First I found it incredibly interesting how long it took me to get into ketosis! After two days of eating more carbs it took me three days to be in nutritional ketosis. I did plan it that way on purpose – I wanted to know how long it would take my body to get back into that state after a carb heavy weekend. I truly expected it would be a day or two! That really interested me. I’ve been eating low carb for years, ketogenic for a year, so I honestly thought it would be faster!
I had my highest ketone levels after a good workout (30 minutes of weight lifting and hiit) and a long fast (I think 20 hours). It’s funny because I know this. I know the three ways to reach nutritional ketosis is through carb restriction, fasting, and exercise. Yet it wasn’t until I saw those numbers that I realized the effect they can have for me personally. I always tend to feel my best when I fast longer (18-20 hours) and obviously I love exercising. So seeing how it affects my ketones makes sense and makes me pretty happy 😉
I did find that because I knew I would be testing I was a bit more focused on what I was eating than normal. And I felt amazing. I truly feel so good in ketosis! So it was a handy way of holding myself accountable.
So, should you measure? It’s up to you. Be honest with yourself as to why you want to measure. I honestly came at this to learn about my body, not to chase ketones. If you’re someone who has a poor relationship with the scale, weighs daily, and allows that number to dictate how they feel then it’s probably not a smart choice for you. If your simply interested in what affects your ketone levels and you don’t mind the cost then go for it!
I’ll personally go through times when I choose to use it but most of the time I’ll just do my thing. Eat real food, keep carbs low, and move my body.