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What counts as a blood sugar ‘spike’

If it was only the two hours after from pre meal, I would say, that the reading would be borderline, and with glucometer not being as accurate as you would wish, it in my opinion too high. I would be looking at much nearer the pre meal.
Along with that view, the spike is relatively high at the hour mark.
It is the abnormal spikes that is the ones to avoid.
You have a normal pre meal reading, but the spike reading is too high, that to me for the food you have had is an abnormal reading. And to be avoided, either by portion control, having some good fats, or by avoidance.

It is a huge learning curve and you will learn so much from all the experiments you do.
I would agree with everything above, excellent advice.
And add, that I used a food diary to help with my discovery of what I should eat, and those I shouldn't.

my spike is around 45 minutes to an hour after first bite, if I have one, out of normal levels, but because I have knowledge of what my body can tolerate. And I don't want to have spikes higher than 7mmols. But that is me.
it will be different for you.
so keep asking, keep testing, start recording your meals and results.
best wishes.
 
If it's any consolation, I became obsessed for a while too. In all honesty, if you're going for the diet managed T2 route, I think you kind of have to become obsessed while finding your way with a new diet. I used to test first thing in the morning, before and 2 hours after every meal, sometimes I'd also test during and after the 2 hour window too, then I'd even test before bed to see what was going on. I was burning through up to 10 test strips a day at points for at least 2-3 months, testing everything I ate and tracking trends. Armed with this information, I reduced my hba1c from 83 in July 2023 to 29 in my latest blood test, however for the last 6 months I've been in a more settled routine with diet (thanks to the testing marathon in the first 3 months) and I don't test anywhere near as often.
 
In my limited experience, blood glucose levels can vary depending on what I eat, how much of it I eat (portion size) and when I eat it - morning, afternoon or evening.

For example, it looks as if you monitored after having one slice of bread. I have found that one slice of wholemeal bread is fine (ie a rise but no big spike), even at breakfast time. However, two slices, such as a sandwich, can cause a spike, even later in the day - but not always. I haven't tried potatoes or rice yet as I only started monitoring in late February and have been avoiding those foods. As another example - I can't eat a large portion of sweet potato in the evening (say 350g), but I can eat a smaller portion (<170g) with greens and steak for example.

What I'm saying is that it might be down to portion size and time of eating. That is, provided you keep the portions within the above limits they may be fine in your diet.
 
I’m going to try testing at these intervals tonight with a mediumish amount carbs meal (200g potatoes) and then Saturday evening with a very low carb meal (under 30g) to see what happens.
I’ll keep testing in the hopes one day I can stop testing
Thanks for your reply.
 
Your favourite food is something I haven't ate for about nearly fifteen years ish.
And I do understand why.
Anything with chips, was my diet, feeding four children and a busy working life.
And how I miss a chip doorstep.
Spuds are full of starch, which is just another example of a carbohydrate.
And it is the carbs and sugars that spike you.
You may not have to give them up totally, but be prepared to reduce the portion size, to help with controlling your blood glucose levels, and reducing your spikes.
Best wishes.
 
I tested with lunch since I had a McDonald’s: Big Mac and fries with 6 nuggets.

before - 6.1
30 mins after - 6.4
60 mins after - 8.8
90 mins after - 8.3
2 hours after - 6.9

Seem to respond less to the carbs in McDonald’s than the carbs in the pastry of the spring rolls last night. Don’t think I’ll be eating pastry again.

The more I’m testing the more I think I’m just getting obsessed over it. Spend that last 10 days doing nothing but obsessing over blood sugars and reading diabetic forums. Think I’ll just stay with post 2 hours meal and go from there. I’ll also see what my diabetic nurse suggests at the next appointment.
 

McDonald's is high fat and high protein, so that causes slower digestion of the carbs when it all mixes together in your stomach. If the carbs are digested at a slower rate, it can have the positive benefit of allowing the resulting glucose (carried by insulin) to be absorbed at a rate where your insulin resistance doesn't cause a build up of glucose in your bloodstream.

Spring rolls (and pastry products generally) are quite a high proportion of carbs to any other macronutrient, so there's not much chance of carb digestion being slowed. Pastry has a significant impact on my blood glucose levels and I seem to remember @KennyA saying on another thread previously he'd experienced the same with it too, so you're not alone with it.
 
If I was doing this experiment (which I would never do as it would make me feel so yucky) the following would be my testing regime
Test at first bite
1 hr
2hr
3hr & depending on the 3 hr reading possibly 4hrs too

I bet you a chicken nugget to a chicken breast in a cream sauce my readings at 1 & 2hr I would see pretty much what you have, my 3hr & 4 hr would continue to rise again probably into double figures and stay up probably in the high 6s to 7s for a while after that too

as @Paul_ says it’s high fat as well as high carb so the fat will have slowed down the absorption of carbs.
 
I think it was this thread, someone said about pastry. Glad I’m not alone in that. Knew I should have had rice instead of the spring rolls. Definitely will be avoiding pastry products from now on!!
 
I don’t have any foods that make me feel yucky. I’m quite lucky in that respect. Very lucky to not have any symptoms (yet) either.
I did test after 3 hours but it was reading the same 6.8.
Had done my blood sugar about an hour ago (4 1/2 hours after the McDonald’s) before some toast for dinner and reading was 5.9.
So I should be trying to include some fats into my diet?
 
The reason that the food would make me feel yucky would be the high BS not the food itself, high carb high fat isn’t a great diet for anyone never mind someone with T2, if you reduce your carbs then including more good fats in your diet would keep you fuller but I wouldn’t recommend upping your fats if you are still eating lots of carbs.

I eat 20g or less of carbs a day and I eat normal fat not high fat
 
Should you Emilymay be going low/no carb. Your BG will not improve if you eat lots of carbohydrates.
 
Picking up on an old thread here after doing a search. @KennyA apologies (kinda) for tagging you directly, but your knowledge in this area is far greater than mine, but I wanted to pick up on the mention of alcohol and ask a question. I like a glass of wine or three a couple of times a week, namely Friday and Saturday. I've noticed that my 2hr readings are on the lower side when doing so. I understand that alcohol can lower the readings, however for clarity (and I'm still trying to get my head round it despite reading numerous articles, papers etc.) are we saying that though alcohol gives lower BG readings that the BG is actually likely higher and still doing damage? Also how would that show later when HbA1c tests are done?

I've potentially not phrased that exactly right, but hopefully you understand what I mean?

Many thanks
 
Hi @Keith Saunders

As a T2 on keto I’ll give you my experience with alcohol, if I have a couple of drinks and stick rigidity to keto then I see no markable changes, BUT if I have the same amount of alcohol and go off plan a little, only when I’m eating out do I maybe have a few carbs, maybe a few chips or onion rings or very occasionally a bit of hubby’s pudding.

When I test on these occasions my BG can more often than not be lower than expected, but I will see a rise a few hours later & my BG will be slightly higher, and it will run a little higher than normal, though still in my acceptable range for a couple of days.

Alcohol is technically a poison so your liver will work hard on that first to get rid, pushing the carbs to a back seat, once the alcohol is dealt with then it deals with the carbs which can result in the bit higher readings for a while. Alcohol doesn’t negate only delays the outcome from carbs
 
My understanding (albeit from a T1 perspective), is that our livers are single minded - they can only focus on one thing at a time. Or rather only one thing that can affect our BG if we are being pedantic.
Most of the time, this one thing is a constant drip of glucose. In an ideal world, this would be the same amount of glucose dripped 24 hours a day. However, there are some ups and downs, most noticeably the morning dawn phenomenon glucose dump to give us the energy we need to start our day.
A healthy pancreas will release the required insulin to convert this glucose to the required energy. So most people are completely unaware of this.
To my understanding, our livers do nothing with the carbs that we eat apart from storing some of the glucose to drip later.

The other thing our livers do which affects our BG indirectly is to dispel toxins like alcohol. And when it is sorting out these toxins it does not drip glucose. Hence, we see a reduction in BG whilst our liver is focused on the toxin.

A bit of Type 1 treatment explanation (I promise this is relevant): most people with Type 1 take two types of insulin - a fast acting which we take with food and a background (slow acting) insulin that only works with this liver drip. Because the slow acting is usually taken once a day (unless using an insulin pump but let's not get into that here), it designed in the assumption that our background insulin needs are constant throughout the day. Once the slow acting insulin is injected, it is left to work over the next 12 or 24 hours and we cannot do anything to speed it up or slow it down. So, if we drink some alcohol and our livers stop dripping, we have too much insulin un our bodies and we are at risk of hypo (low BG). This can last up to 24 hours.
(Back to the stiff for everyone regardless of Type 1ness) Once our livers have finished dealing with the toxic alcohol, it goes back to dripping glucose in its usual merry fashion. It does not drip extra glucose to make up for the stuff it missed earlier. So, there is no later rise from alcohol when it then "deals with the carbs". Our livers do not "deal with carbs", they continue to be digested in the same way as they would if we weren't having alcohol. The only difference is the lack of drip from the liver.

It is interesting that @lovinglife experiences a later BG rise once the alcohol has been dealt with. I am not sure why this is. Maybe (and this is pure speculation), it is a result of the other negative affects of alcohol (feeling lousy, less exercise, etc. ). It is nothing to do with a delay in dealing with the carbs.
 
I understand the question (or I think I do).

I can't give you a definitive answer. My take on it is that the carbs go in and still have to be dealt with as they would in the absence of alcohol. Because what we're seeing from alcohol is an impact on the liver's making of glucose, rather than any impact on the glucose deriving from eaten carbohydrate, the blood glucose level post-food is automatically lowered because we're shutting down one (but only one) of the sources of blood glucose. Although carb from food is generally accepted as the single biggest impact on BG levels, it's the liver that sets and maintains what it decides are the current requirements.

It's a bit like counting up how many goals your crack centre-forward scored over the last season and noticing he scored fewer when you artificially excluded goals scored in the Cups from the calculation... but while fewer overall it doesn't alter how many were scored in the league.

In my case I also consistently see lower +2hr figures than I would normally expect - this has included having a very carby meal on one notable occasion and winding up with a lower BG than I started with.

What no-one seems to have done any work on is what happens to the glucose from digested carb after a meal with alcohol. Until recently not all that much work had been done on what "normal" BG levels looked like, and the advice from health services is always to reduce or stop alcohol intake. This seems to lead on to a belief that it's not therefore necessary to find out what happens to blood glucose etc when people don't follow the no drinking advice. A CGM might be the best way to get some personal data but given the inherent inaccuracies of all the home testing I'm not sure it would be able to pick up impacts consistently.

So - the BG is not (I think) "really" higher - it is, after food with or without alcohol, what the glucometer or CGM measures it at. The glucose presumably winds up (as it would without alcohol) either in stores in muscle and the liver, or in fat, or being used immediately by central nervous sytem or elsewhere. As there is a significant amount of energy derived from digested alcohol (7 kcal per gram) my bet would be that much of the glucose is being stored, and once the liver and muscle stores are full it will be going to bodyfat. That might also mean a higher insulin level for longer (again a guess) which is not something I'd want.

The HbA1c counts the number of a particular type of blood protein that's glycated - had a glucose molecule attached to it - which is a proxy for blood glucose levels over the last 3-4 months. The more glucose there's been in the blood during that time, the more likelihood that red blood cells have been damaged in this way. From what I read, it's elevated levels over time that do the most damage, rather than short term rises such as you'd see after a meal your system can handle.

I don't know, and I'm not about to find out, whether this alcohol impact on the liver might fade (or get worse?) after consistent and prolonged alcohol intake, meaning the rest of the body adjusts and glucose levels return to where they would have been or higher.

A further point that I can't stress enough is that if you're running low BGs anyway (via low carb or equivalent) completely shutting off the glucose supply from your liver through alcohol can be positively dangerous. It has happened to me once, and once is more than enough. I hadn't eaten, and was more worried about the level of carb in the beer - my big mistake. It led to a full-blown hypo. Please never do that.

Sorry I can't be more definite, but there seems to be a marked lack of research in this area.
 
Definitely not the negative affects of alcohol- I only have 2 or 3 drinks at the most and I don’t feel lousy, do less exercise etc - no changes except if I have more carbs than normal, don’t have those carbs & drink and I see no difference than without the alcohol.

My reply was to a T2 diet only same as myself, I’ve no idea how alcohol affects someone with T1

Edited to add more info
 
Just popping in to support @KennyA in his discourse about digested carbs in the presence of alcohol. There are quite a lot of these kind of blind spots in the literature, and it makes learning as a layman really tough. The accepted position is that the Liver prioritises metabolising alcohol first, as it's the only organ in the body that can, and otherwise alcohol is toxic. This, interestingly enough, is exactly the same for Fructose, which of course, is only alcohol that has not been fermented (to be clear that is a definite over-simplification, but it bears repeating that alcohol does a bunch of additional things, but at the base level, is just another form of sugar).

But - as @KennyA says - if the liver is busy dealing with the alcohol, the digested carbs don't just disappear, they will be broken down into base sugars and transported to the liver as normal, then what happens can only really be this;

We talk about the liver "prioritising" - because we are human, and tend to explain things by personifying. The liver is of course, not deciding or prioritising anything, just sending signals to the Pancreas to stimulate the hormones to manage sugar levels, Insulin if high, Glycogen if low.

Reading through the thread again, (and I'm casting no stones here at all, I'm certainly a slave to data, obsessed with measuring everything until I feel that I understand a process, it's literally what I've trained to do my entire life) there is a danger in focussing on Glucose. Blood Glucose levels are of course a problem as a diagnosed Type 1 or 2, but it's really a question of Insulin. Wearing a CGM, you can definitely learn a lot about your body's response to different foods, but in the end it's about reducing the repeated, elevated levels of insulin which is the major (but not only) driver of Insulin Resistance.

Coming back to the specific topic (and I promise there was a need for the detour) - what happens to the digested carbs ... depends on your current response to insulin.

A younger person (and we know this instinctively) with a "good, sensitive" response to insulin, will have a flood of insulin, that will kick off a bunch of processes, leading to the alcohol and sugar being metabolised quickly and packed away in the muscles and fat storage tissue, often leaving a lower BG than the starting point (this is normal, and again, we instinctively know this, with the morning after cravings). But - a person with insulin resistance will have an even higher flood of insulin, but not nearly the same effect. Don't want to get into more detail than that, but for sure, a CGM will give you insight, and for sure, at least in my experience, not having that alcohol or carbs makes this all much easier, and you don't have to worry about the numbers, because it turns out that the liver is super effective if you give it a chance (and for me that means accepting that I really have been making things difficult for my liver for several decades, and it deserves a break)

Just to add, in case I sound like a prissy teetotal convert - I've had a whole bunch of fun in my life related to alcohol, I'm not in any way judging - just that as I reduced drinking in the last couple of years, my tolerance reduced as well, to the point that I now get a headache and my head starts to buzz even with a single glass of fizz. I've just gotten to the point where I'm happier overall not drinking anything.
 
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