Keto made easy

How to Read Ketone Strips in One Minute: Ignore the Colour, Check It Reacts

2017-07-19

A one-minute phone clip from July 2017, about five weeks after I started keto in mid-June (video cTGYIFOTPl8). It covers the one thing most beginners get wrong about urine strips. It was never uploaded to YouTube.

In this recording

Watching this in 2026

The advice still holds, and it's still the advice people need most. Beginners post photos of dark purple strips as if darker meant better, then panic when the strip fades in month two. One minute was enough to cover both mistakes.

The prices are 2017 prices, from me, at the time. Check current ones before you buy anything.

What I'd add is the other half of the story, the part I only got to later. In a video uploaded two weeks after this clip, I called keto sticks my favourite keto item (video DWI8qQl5BbY). By 2019 I was telling people they don't need a monitor at all, and that a meter is mostly trivia (video 1JbK1_ClDmY). Those fit together. A strip is useful when you're new and want proof the change is working. After that it tells you less and less, which is exactly what this clip says.

The claim worth unpacking: "a negative strip can still mean ketosis"

I said that once you're heavily fat-adapted, ketones stop spilling into urine even though you're still in ketosis. Here's what the evidence pages support.

The liver makes three ketone bodies: acetoacetate, beta-hydroxybutyrate (BHB) and acetone (StatPearls, Ketogenesis). As I said in the clip, a urine strip picks up only one of them. A blood test is a separate measurement of what's circulating.

The adaptation part fits the classic fasting research. In Owen et al., 1967, after weeks of fasting, BHB and acetoacetate replaced glucose as the brain's main fuel. No study on the evidence pages tracks strip colour over months of keto directly, so "six months to two years" was my estimate, not a measured figure.

"If it reacts at all, you're in ketosis" is a reasonable rule for a healthy person eating low carb. It is not a rule for someone with diabetes. Ketone levels in nutritional ketosis and in ketoacidosis are very different, and monitoring in diabetes is its own subject (Laffel, 1999). If you have type 1 diabetes, take insulin or other glucose-lowering medication, or are pregnant, your doctor decides what a strip reading means for you.

Key points