2 hour readings after dinner - questions

[Dougie22]

The story so far.

Diagnosed at Easter and reasonably successful so far at getting HbA1c under control. have been on this forum since diagnosis, read a couple of books and been on DESMOND course. Frequently self testing but paying for my own strips. Happy that my understanding is growing and I now have quite a long list of breakfast and lunch food combinations that I can tolerate. Generally, I'm following a reduced carbs, calorie controlled, low GI style diet and going to the gym three times a week. Lost about 2.5 stones to date, mostly in the early months. Fall off the wagon once in a while.

Having followed the "Fasting level this morning" debate and experienced big differences in readings seemingly more dependent on when I get up than what I've eaten the day before, I've decided to reduce the frequency of fasting testing and concentrate on post dinner readings for a while.

Two weeks ago, I started using an on-line calorie and carb tracker (Myfitness.com) and I've been religiously recording absolutely everything I'm eating.

Although my testing has been patchy (so, for example, I may have tested 2 hours after dinner but not had a pre dinner reading for comparison), the results haven't been as predictable as I thought they'd be.

Perhaps optimistically, and all things (GI especially) being equal, I'd expected my 2 hour readings to vary more in less in line with the grams of carbs consumed. Results so far don't seem to show this happening and readings seem to range from around 8.5 to around 10 with similar carb loads?

I'm now going to start a more rigourous before and after set of tests and I'll report back the results in more detail when I get them.

I'd be interested in what the more experience carb watchers/self testers think.

Is their a direct (linear) relationship between carbs consumed and BG level?

(Sorry for the long post)

 

[hallii]

I find that there is not a direct relation between carbs consumed and BG levels.

Some carbs in some foods seem to have little effect on my BGs whilst others have a dramatic effect.

It all comes down to the fact that we all vary, you have discovered foods that you can eat and some that you cannot, it is the same for all of us.

Why I can eat chips ( yes good old fried potatoes) without major problems but not boiled potatoes escapes me, but it is so. I just have to accept it (not that I mind ).

I can eat pupadoms (a couple) but not bread and so on.

So eat what you can cope with, don't eat the things that affect you.

H

 

[Dougie22]

On another note but completely related, where does GI come into it.

Obviously, If I eat the same amount of carbs (of very similar foods), then if they are low GI they give out their BG effects over a longer period (sometimes much longer) than would a high GI type.

Yet we all talk about (and the NICE guidelines discuss) the 2 hour after eating results.

My guess is that it's safer to have a slow release than a fast, peaky one but then maybe I shouldn't be concentrating on a 2 hour reading.

A case in point is my wholegrain rice, chicken and chorizo dinner tonight, wher the readings went as follows:

Before meal (at 5.40) BG 5.5
2 hours after (at 8.30) BG 8.9
(at 9.00) BG 9.9
(at 9.30) BG 8.2
(at 10.00) BG 7.0

I can't possibly test as frequently as this, it's a one off due to cost but quite revealing in that the 2 hour reading was well below the 2.5 hour reading).

So what test do I use to determine what I can eat and what I can't.

Until now I've used two hour reading less than 8.5 as my indicator , without taking a pre- eating reading.

Is this still a valid measure?

The more I find out, the more complicated it gets.

 

[the east man]

Ive posted this web site on a few threads, and so far I have found, for me,these are the readings that I aim to achieve. As you will see the targets are lower than our NICE targets, maybe thats why so many T2s end up on medication. Have good look through the site, I have found it very helpful, but again, as Ive said this is what suits me, everyone is different.
http://bloodsugar101.com/

 

[Dougie22]

Hi East Man,

I've not had a good look round the web site yet but will do.

I have, however, bought and read the book and I'll re -read it over the next couple of weeks.

At the moment, these targets are too strict for me and would be wholly impossible to reach without a dramatic change to my diet and, indeed, life. It may be that I eventuually come to the conclusion that these changes need to be made but I'm not there yet.

I'm lucky that I seem to be able to get my HbA1c down with less drastic changes and at the moment I'm concentrating in gradually losing weight and reducing my carb intake while learning more.

But regardless of how tight a target you set, the questions remain the same, namely:

* Why are some foods ok for an individual and some aren't - it's more than just carbs (see below) - has anyone done any studies to determine whether there's any consistency across the T2 population?

* How can one timeline cover high GI and low GI foodstuffs when we know they supply their energy at different rates.

* What science/studies lie behind the two hour recommendations (Nice at 8.5 for example)? I'm not aware that there have been any detailed studies that would indicate that, say, 8.5 after two hours gives better long term control than a higher number after 2 hours or another number after 3 hours. I will re-read Jenny's book to see if I missed this first time through (quite possible).

I'm currently measuring very carefully over dinner and will post some results here when I get them.

As an example, I had a large dinner tonight, 1022 cals and 113g of carbs. This on a big full day of 2005 cals and 251g carb (a bit more than normal). My readings were 8.2 after 2 hours and 7.4 after 2.5 hours (within the range I'm currently aiming for - unexpected!).

By comparison, last night's dinner was 834 cals and 85g carb, on a day totalling 1777 cals and 182g carbs, yet my readings were 8.9 after 2 hours, 9.9 after 2.5 hours, 8.2 after 3 hours and 7.0 at 3.5 hours (well over the range I'm currently aiming for).

As it turned out, the dessert was the same both days and I had chocolate with my coffeee today so it looks like the rice I had yesterday was much worse for me than the potatoes I had today.

More worryingly, the numbers are so different that it doesn't seem that I can even predict what will happen using any of my measures - meal cals and carbs or total day cals and carbs.

What's special about rice and why would it raise my BG so far? What other foods are special in this same way?

This was wholemeal rice. Do I now try other types? Could be testing a long time!

 

[the east man]

I think you are 100% correct. This illness is far from being an exact science, thats why I when I post I write "this is what works for me". I'm pretty much a creature of habit, and I like to plan and think ahead, but with this disease its just mostly trial and error, and really takes me out of my confort zone. I thnink unless we eat the exact same things every day, at exactly the same time every day, go to bed and sleep at the exact same time every day, and sleep for the exact same length of time every day, excercise the exact same time every day, and do the exact same workout everyday, there will always be ups and downs in our BG levels for no apparent reason. It's just about controlling it as best as possible to cut down your chances getting the side effects of bad sugar levels :?

 

[phoenix]

I'll answer a couple of questions about GI

Why are some foods ok for an individual and some aren't - it's more than just carbs (see below) - has anyone done any studies to determine whether there's any consistency across the T2 population?

Many of the GI tests have been done on people with T2, in fact the very first tests were done on people with T2, but the rankings are averages of the people tested. Some people will inevitably have higher glucose spikes and others lower and we will all differ from day to day.
There are lots of reasons for that eg: prior exercise, amount of insulin resistance, the type of flora you have in your intestines, how long it takes the food to pass through your stomach (this varies and many people with D have some degree of autonomic neuropathy which can slow this).
The GI ranking of a food can help you choose which is most likely to be a better choice but experience will tell you if some are better for you as an individual than others.

*

How can one timeline cover high GI and low GI foodstuffs when we know they supply their energy at different rates.

In a mixed meal the overall GI can be worked out according to a formula ie multiply the percent of total carbohydrate of each of the foods by its glycemic index and add up the results to get the glycemic index of the meal. In trials this has been shown to be a good indicator of overall effects on glucose levels.. The University of Sydney describes a low GI diet as being one that has an overall GI of 45 and below.
Most people using the GI as a basis don't do lots of complicated calculations but lower the overall GI by choosing lower GI starchy carbs over high ones and for the most part avoiding highly refined, high sugar foods.
They may also take into account the glycemic load (ie take into account the amount of the carb and the GI) You can do that by conciously using moderate portions of starchy carbs (I still weigh them at home, but I have T1 and need to inject)

What's special about rice and why would it raise my BG so far? What other foods are special in this same way?

Rice is a natural product with many different varieties. There are 2 types of starch, one of these breaks up very easily during cooking and during digestion. Rice containing a lot of this type of starch ends up soft and fluffy, even sticky (jasmine rice) These rices can have very high GIs, some are higher than glucose. Others have higher levels of another type of starch which breaks down less easily. These rices are lower in GI. Basmati is one of the rices with a lower GI, as surprisingly, is Uncle Ben's converted rice (not very low but ones with very low GIs aren't easy to find).
Any rice will have a higher GI if it is cooked beyond al dente(same with pasta), the cooking process will have made the rice easier to digest.
Personally I go for a mixture of wild, basmati and 'brown.

There are lots of answers about the GI here in the FAQs. There is a database of GIs.
http://www.glycemicindex.com/
The newsletter is also a good resource

 

[Dougie22]

Phoenix,

Thanks for this. This is exactly the kind of response I was hoping for.

I'll read up on your link when I get the chance.

 

[didie]

I do eat the same things every day, do the same exercise every day and go to bed at the same time and my readings still fluctuate, though they are dropping.

 

[jowatkins]

Thanks for your question. I am newly diagnosed type 2 and am having exactly the same reponses as you and my BG levels are very similar to yours. I can even get totally different BG levels after 2 hours on different days after eating the same meal.

It seems to me that the saying `it works for me' is the key. Everyone reacts differently to foods and we just have to find out what meal combinations work for us. I cut out bread entirely at first but just recently have had a few slices of `good' bread which does not seem to have had much effect on my BG levels but has stopped me losing weight this week.

It's interesting to hear that someone can have chips but not boiled potatoes!

I am getting frustrated as nothing seems to be consistent with my BG levels and meals. All I am doing now is trying to stick to a low GI carb (and low carbs in general) diet and see if losing weight gives any improvement.
Jo

 

[Grazer]

Hi Dougie, following on from Phoenix's excellent reply, the 2 hour thing is really a best-guess average to use, to axchieve some sort of consistency for comparing measurements. You'll never get a time scale which is spot on for recording peaks, even if you eat the same food stuffs. As phoenix says, the activity before or after will affect the rate of rise and fall, and the duration of a rise, as will many other factors like GI and the mix of foods. Some nuts with a meal will change the GI for the whole meal. A glass or two of wine will have a major impact on the BG for the same meal (much lower with wine) Some reports show that strong black coffee, with zero carbs, raise BG as the caffeine increases insulin resistance. Green tea, however, despite a heavy caffeine content, reduces BG. The reports aren't clear if this is a long term consumption affect, or short term, but show that there are factors on top of carbs that affect things potentially. Even with all factors being the same, results vary as our perhaps slightly dodgy pancreas fires up inconsistently. All we can do is try to get a reasonable figure consistently at a fixed stage to keep our overall averages down.I've found it easier as time has gone on, and my BGs seem to become more settled and consistent.
The rice thing is the same for me; Sainsbury's easy-cook basmati is rated by some sites as the best GI rice. I use it with good results. One site shows it with a GI of 48 compared to one make Jasmine rice at 86! HOW you cook food is also important. The use of fat slows down the rate of production of sugar, so I find that the same amount of old potatos pan-fried are much better than boiled for BG. Same carb count, same Glycaemic load, (GI x grams) New potatos boiled are fine, but old ones release starch as they boil (hence the fluffiness) and are a killer. Ditto jacket potatos.
In terms of consistency between T2s - there isn't much! Not even on time of day affecting BG. I can eat a load of carbs at breakfast with very low 2 hour readings, but the same amount later in the day will send my BG high. Others are worse in the morning and better later.
I tried to be overly scientific with exact timings of peaks, difference between before and after, but ultimately, our meters (unreliable in themselves) are only there to give us a guide., Big rise, bad, small rise, good!
But you're right - the more you learn, the more you realise how complicated it is, and the more there is to still learn!

 

[Etty]

Another thing to consider is the high level of carbs you are eating. If you lower the carbs, your readings will be more stable.

 

[Dougie22]

Thanks for these really informative comments which really do help me to put my readings in context.

My intention is to concentrate on dinner readings and continue to try to get to 2 hour readings less than 8.5 (obviously lower if I can).

Where suspicious, I'll take extra readings to see what's happening if I can.

Will try and isolate rice as an issue and try different types.

My main aim at the moment is to continue slowly losing weight and get my HbA1c below 6.0 if I can.

I'm also kind of setting a solid baseline of information that I can refer back to in years to come if my general BG control becomes worse over time.

 

[Dougie22]

Tonight was a bit strange when I fell off the wagon (agian, I'm afraid).

Total of half a bottle of wine and a feed of chocolate with my coffee.

So interestingly 5.6 after 2 hours, 8.6 after 3 hours.

I'm assuming the 5.6 was a result of the alcohol, and the 8.6 the underlying reading coming through.

Not that relevant because I don't want to do it often but interesting in its own right.