• Guest - w'd love to know what you think about the forum! Take the 2025 Survey »

Spike at 30 minutes

S

Sapien

Well-Known Member
Messages
140
Location
United States
Type of diabetes
Prediabetes
Treatment type
Diet only
I had a fasting blood glucose of 5.8 mmol (105 mg/dL) on a lab test. Two tests were both about the same level. My A1c was 5.0%. My doctor says I have impaired fasting glucose. I got a meter and have been testing my response to carbs, protein and fat.

Today I ate breakfast which included a veggie omelet, about a cup of beans (pinto) and some sweet potato. I tested at 1/2 hour 9.6 mmol (172 md/dL), 1 hour 6.7 (120) and 2 hours 5.7 (102). At 3 hours I was back to 4.7 (88) which was about the same as fasting upon waking 4.9 (89).

I have read that most people only test at 2 hours (sometimes at 1 hour). If I only tested at 2 hours I would have never seen the big spike. I would have thought the carbs didn’t have such a big effect- only +0.7 mmol (13 mg/dL).

How concerned should I be with the spike at 1/2 hour?

It seemed really high to me. My understanding is any time the blood sugar goes over over 7.8 mmol (140 mg/dL) not normal and can lead to damage. It isn’t clear for me if a short spike like that if really bad or not. It makes me want to test simple carbs at 1/2 hour to see how high they would send me. I have normally not seen any numbers over 8 (144) at one hour or 6.7 (120) at two hours.

I have noticed that when I eat more carbs than protein/fat that the spike is quick and when I eat mostly fat/protein with only relatively little carbs that the rise is of course much less but takes longer to peak - usually closer to the one hour mark.

One other thing I have noticed is that when I wake up my blood sugar is usually between 4.5 (81) and 5.1 (91), if I don’t eat for a couple hours it rises sometimes as much as 0.8 (14). If I eat just a little fat/protein (e.g. a bit of cheese), it will drop a bit from the wake up reading.
 
Testing just 30 minutes after eating won't tell you much. It's better to go by the test at least one hour after eating, which was fine in your case.
The beans and sweet potato aren't good, and best avoided.
 
I am trying to find which carbs (or quantity of carbs) make my blood sugar go over 7.8 mmol (140 mg/dl) at any time. Aren’t short spikes also damaging?

My target is to get my fasting to 4.6 (82) consistently and see no 1 hour over 6.6 (120) and stay under 5.5 (100) most of the day.

I have been trying too stay low carb but I have found that I have lost too much weight. I want to add more carbs back in but keep the spikes as low as possible.

Maybe I should try another strategy to keep from losing more weight?
 

The best strategy to stop losing weight is to NOT increase the carbs, but to increase the fats and protein. You can increase the number of eggs you eat, put generous knobs of butter on your vegetables, increase your dairy foods in general, eat avocados if you like them (I don't), eat more cheese. I was in a similar position to you in 2014. I actually lowered my carbs to help the blood sugars and increased my fats and protein. It took a while to find the right balance, but once I did, my weight stayed stable and has been ever since.
 
I think adding carbs back into your diet would be counter productive. To halt your weight loss add a little more fat to your diet. You shouldn't need much maybe a little extra olive oil on your salads or a hand full of nuts. It will take some trial and error but you will eventually find the right balance.
 
Prem51 said:
Testing just 30 minutes after eating won't tell you much. It's better to go by the test at least one hour after eating, which was fine in your case.
The beans and sweet potato aren't good, and best avoided.
Click to expand...
Doesn't testing at 30 mins compared to 1 hour also give an indication of a fast or slow insulin response? I read somewhere that a high spike at 30 mins might show your insulin response is sluggish and not dealing with the carbs, whereas a spike at an hour shows a healthier response. I could be wrong but I think.I read that somewhere.
This article has something about it I think https://www.diabetesselfmanagement....glucose-management/manage-high-blood-glucose/

It could be talking about insulin dependent diabetics though and their (in)ability to match their insulin doses to the carbs they eat. I'm not sure. I still want to know whether a higher spike at 30 mins Vs 1 hr has more to do with what you eat (ie, mostly carbs VS carbs with protein and fats) and which one is the more healthy response. Anyone else know?

Could also be the response to High GI carbs VS low GI carbs that I was thinking of where High GI spike hard and fast (by 30 mins), then drop off and sometimes end with the BG being too low, whereas Low GI carbs spike lower and slower (by one hour) and don't drop your BG as much afterwards.
 
Last edited:
Jenny Ruhl writes in chapter four of her book “Blood Sugar 101” that testing at 30 minutes frequently will show a higher peak than testing at any other time, but that research shows that blood sugar spikes that resolve before one hour don’t seem to damage organs or even out raise A1c. She didn’t cite the specific research. I wonder how true that is.

I guess it makes sense to test at one hour to see important spikes from carbs or two hours to see if blood sugar drops back after eating or remains elevated.
 

Everyone’s blood sugar increases after they eat. It’s how the human body works. But in normal people their sugar at 2 hours would return to normal levels. A spike is when it stays too high because the insulin hasn’t worked properly to bring it into normal range.
So a spike at 30 mins is normal because thats how the body works.
If I tested st 30 mins I wouldn’t be able to eat anything!
 

Why wouldn't you be able to eat anything if you tested at 30 mins?

The thing about the spikes is that the foods that cause higher spikes in everyone, even non-diabetics, are probably the foods that damage our bodies and eventually lead to insulin resistance and T2 diabetes. Isn't that how it works? If someone eats a diet that only includes foods that cause spikes to say 6 or 7 mmol vs someone who eats foods that regularly cause spikes to 8, 9, 10 and into the teens, the extra insulin required by the body to deal with those spikes is problem, isn't it? And your overall blood glucose average would surely be higher too, wouldn't it?
T2 diabetes is not something you are born with, is it? So when you start out your life eating the foods that cause high spikes, your body can handle it for years, with less severe spikes and a faster return to a normal level of 4 or 5 mmol, but after years of this it starts to fail and the.spikes get higher and the returns creep up as well. Please correct me if I'm misunderstanding the way it works...
 

I was being facetious.
 
Did you test before eating that breakfast? Not sure if I just missed it? Personally, if I saw a 9.6 after breakfast I would of retested, sometimes the reading can be wrong (Bad strip, contaminated strip etc). Or if you didn't test before breakfast, then you can't know how much it actually spiked.

As has been pointed out, eat less carbs is a good idea. It's a balance you just have to figure out and it takes time.
 
Cocosilk said:
I understood that you mean you'd prefer not to know how high your spikes are at 30 mins because you're eating naughty things
Click to expand...
I think we all spike whether we eat naughty foods or not. As OP said some protein such as eggs and some beans does raise the BG ever so slightly. I too spike a little with eggs and we all experience to some extent dawn phenomena.
 
Cocosilk said:
I understood that you mean you'd prefer not to know how high your spikes are at 30 mins because you're eating naughty things
Click to expand...

No.
I think when I first got diagnosed whatever I ate I was at the 20s within half an hour. Spike to nurse and she said it’s pointless because everyone goes up that’s how the body works.

My duet is very good.
The very odd mistake but 99% very good.
 
MeiChanski said:
I think we all spike whether we eat naughty foods or not. As OP said some protein such as eggs and some beans does raise the BG ever so slightly. I too spike a little with eggs and we all experience to some extent dawn phenomena.
Click to expand...
We all spike but to different levels depending on our insulin sensitivity though, right? We could do an experiment and ask a number of us to do it, say, eat a 3 egg omlette fried in butter and tell us your 30, 60 min and 2 hour spike, and then do the same with a small banana (say 150g) and measure the same times. Also get your non-diabetic friend or partner to do it as well. Then we'll really see the variation. I might ask my hubby to do it with me. He's scared of having his finger pricked though so I'll probably have to chase him around the house
 
Last edited:

I made my own beans (fres tomato, garlic, parsely with tinned white beans) but I limit it to only half a cup as a side to my scrambled eggs.
I can get away with either half a cup of legumes OR a small slice of my husband's homemade sourdough rye or spelt bread, or half a small banana or better, 3/4 cup of raspberries, and add that to my morning eggs. The spikes might be high 7s and come back to low 6s, which is still a little high. If I try to combine any of the above two carbs, bread and banana, or have a whole cup of legumes or a whole banana, I'd spike into the 8s and still be in the 7s at 2 hours. Thats just me though. Ideally once I finish breastfeeding, I'll probably move away from carbs altogether. Prefer to have 4 - 6 mmol most of the time.
 
Last edited:

For me your number is very good. The spike after carb meal always happens. I know a guy who are perfectly healthy who once did this banana test. His blood sugar after eating five large bananas was 5.5 at 1 hour mark. After that it went down to 4.8 (after two hours). Curious, he did the same test the next day. Only now he tested his sugar at 30 minutes. The result was 11.1 (200mg/dl)!

So I think you need not be so concerned about that one very short spike. I'd be happy if can have numbers like yours.
 
You must log in or register to reply here.
Menu
Log in
Register
Cookies are required to use this site. You must accept them to continue using the site. Learn More.…