You might not have kicked yourself out. Ketone test strips only detect EXCESS ketones. So if you are using them all up, you wouldn't change color. Conversely, you can show pink but be out of ketosis. 37g is a lot to have in one sitting. You might find it is easier to get back in though.

If you're really interested in testing your ketone levels, get a blood glucose / ketone meter. The results can be very enlightening. The meters are practically free, but ketone strips are fairly expensive (~$3 each in the US, though I've heard they are cheaper in England). A bit pricey, but in my opinion investing a few bucks / quid to find your optimal carb and protein levels is money (and blood) well spent.

Plus it's actually pretty damn fun. And if you're American you get to relate to the tons of commercials we have over here targeted at diabetics and trying to get them to switch meters. "Our meter uses less blood!" "Our meter hurts less!" "Our meter reduces grey hairs!" Your mileage may vary on that front.

At any rate, 37g of carbs over the course of a day shouldn't significantly affect your ketone levels the following evening. It's probable that this particular event was due to the lack of correlation between blood and urine ketone levels. Especially if you colored a stick in the morning, when ketone levels tend to be lowest. Though of course the sticks don't tell you your ketone levels at the time, and you may have dumped a bunch of ketones hours before but subsequently gone into a reduced level of ketosis which lead to a dilution of the ketone concentration in your bladder.

Or you may be eating excess protein that is going towards gluconeogenesis.

If you want to be sure, get an actual meter.

Hi there

I've had a peek at your diary too, and if you are only just starting out low carb it is perhaps best to avoid the processed 'low carb' things like the granola, tortilla wraps etc.... Nuts and berries are good low carb snacks but are usually eaten after several weeks on low carb.

My advice- up your calories (You had your goal set to 1000???) and up your fat. Eat more good fats and protein and less atrificial sweetners for the next couple of weeks and I'm sure you'll see an improvement.

and how much is the machine thing that tests ur levels i might invest in one of those?

The meters are basically free, the business model is to give them away and make money off of the strips. I use a Nova Max Plus, which the company will send you for free if you fill out a form on their web site, at a drug store / online for $15-20, or thrown in for free if you buy enough strips. The other popular brand that tests both glucose and ketones is the Freestyle Precision Xtra, which costs about the same.

Of course, ketone strips are about $3 / each, and glucose strips are $0.50 / each, so if you test frequently it can add up. I used to test a couple of times a day when I first got mine, but as I learned how different meals and exercise patterns affected my readings, I've tested less and less. Now I generally only test if I do something unusual food or exercise wise, if I feel excessively tired or energetic, or just for fun.