Large unexpected Spike. Any Thoughts ?

Last week, as an experiment....and probably due to pure greed !.....I ate 2 Magnum minis after having some roast pork and salad for my evening meal. I tested at 5.6 mmol/l before eating but two hours later had a reading of 11.0 mmol/l. two hours after that it had dropped to 8.2 mmol/l and a further two ours later I got 6.7 mmol/l.
OK, so that's my career as an ice cream eater finished !

But today, before my evening meal, I read 5.2 mmol/l and had about 150 gms of roast chicken, some tomato, some red pepper, some cucumber and some cornichons. I then had a small pot of full-fat home-made yoghourt with 60 gms of blackberries. two hours later I tested at 9.5 mmol/l. This wasn't a fluke as I retested immediately to get 9.3 mmol/l. An hour later it was 6.2 mmol/l and another hour later it was down to 5.4 mmol/l
I was surprised to see such an increase as the previous night I'd had a similar meal and recorded readings of 5.4 and 7.3 mmol/l before and after eating.
Today, the only thing I ate was a peach at midday and yesterday I'd eaten nothing till my evening meal.
Yesterday, I'd taken no real exercise but had been fairly active all day. Today, I'd cycled steadily for two and a half hours non-stop before my evening meal.
I'm classed as prediabetique and take no medication whatsoever. I'm following the LCHF regime as best as I can....apart from the ice cream business !....and I'm steadily losing weight.
Is a rise and drop like tonight's out of the ordinary ? So what could have caused it ?

I'd appreciate any observations from you people out there who have a real depth of knowledge about these things.

Thanks again...

bulkbiker said:

Was the chicken mainly breast or did you have the legs and thighs?
Only because when I did my one month zero carb experiment I found that lean chicken caused a spike whereas fattier parts didn't. The blackberries are pretty low carb unless there was something in the yoghurt?

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Mainly breast, but with skin. Yoghourt was home-made full fat.
I re-tested today with the same amount of blackberries and yoghourt only and got readings of 6.1 before, 7.5 an hour later and after two hours, 5.9.
That's more like it ,isn't it ?

Thanks for the reply.

pleinster said:

I'd say tomatoes are nasty things. While the two hour reading was high, the one an hour later was fine. I have found, personally, that my system works a little slower than average ( and I am hardly alone in this) and that it takes closer to three hours for my blood sugars to come right back down, so I generally test before and about two and half to three hours after. I would be a bit concerned if I hit a spike of over 9mmols in between if my meal was very low on carbs...but not as much as I would if it was that high at three hours. We differ..the two hour "border" is not set in stone. However, don't forget that all kinds of things from small infection to stress or dehydration can increase our blood sugars, not to mention the impact of certain other meds we might take...and there are "blips" with testing strips and the odd inaccurate reading. I would worry more if it is a pattern.

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Thanks for the reply pleinster.
I think that my system is a bit slower than others, like you. I do tend to let meals....well to be exact, my only meal !....drag out a bit, so I usually test 2 hours and 15 minutes after the first bite.
And yes, you could be right there, as it was really quite warn yesterday and I was out on the bike a bit longer than usual. I thought that I had kept myself well enough hydrated but later yesterday evening I managed to get through 2 litres of water.
My results today are reasonable enough so I'll just keep testing and watching the pattern.

bulkbiker said:

Yes that sounds much more like what I would expect.. did you double check the previous rogue reading you could have had a contaminated finger or strip.. or it could jus be your body taking you for a ride..

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Hi, bulkbiker,
Yes, I did double check that high test yesterday. Re-washed hands and used a different finger and got more or less the same reading.
...or maybe my body was taking me for a ride ? Distinct possibility with my body !
Still, I won't die of boredom.

Thanks again.