When To Test After Meals

When we first received our brand new blood glucose meter the majority of us were told by our doctor or qualified diabetes educators to test twice daily - before breakfast, also known as "fasting" and before the evening meal. Some, not many, of us were also told to test occasionally two hours after meals.

The "us" I speak of are the thousands of newly diagnosed type 2's I've met in cyberspace over the past four years. Over that time, in three diabetes usenet newsgroups, eight Yahoo diabetes newsgroups and a couple of others via the web, I have yet to meet a single newby who was told by their doctor to test one hour after every meal or snack. In fact I've only recently met a few who were advised to test one hour after any meal at all.

So, why do I recommend that we should? Well, I must admit - it wasn't my idea; I learnt it from Jennifer and her Test, Test, Test advice. I also learnt from Derek Paice and his e-book Diabetes and Diet

Any test is wasted if it neither informs nor confirms some information. The tests prescribed by your medics are designed to help them analyse your progress, to assist in their decisions for your treatment - but they do very little to help you personally manage your diabetes. The doctor wants to see your "static" numbers, not the ones that might be very high or low as a result of the carbs you ate, or ignored, at your last meal.

And that's why I add those one-hour post-prandial (after-eating) tests - they help me directly. They are the "dynamic" numbers that showed the direct effect of the food I ate and the exercise I did. I call them one-hour, but the real term should be "peak" or maximum "spike"; mine is one-hour but you'll have to find your own.

I don't think the timing of the spike is as important as it's peak level and duration.

Think about it logically. Why would a spike of 10(180) affect you any differently if it occurred at 30, 60, 90 or 120 minutes? It's duration would be a factor - but post-prandial timing of the actual peak should be irrelevant. It still got to that peak, no matter when it occurred.

So, I learned to find my peak. That is slightly different, but reasonably predictable, with different foods and meal mixtures. Drinks, like OJ, spike me very quickly within 30 minutes and drop just as quickly. Which is why some people use them as hypo treatment. Starchy carbs, without much fat, will spike me in 30-45 minutes. But add fat - and it's about 60 minutes. A normal meal combining moderate fat, protein and low GI carbs leads to a peak at 45-75 minutes for me, and so on. That's why I settled on using the 1hr post-prandial test as my guide, but I occasionally do a 30 minute one if the food was low-fat and high-GI.

As to whether a brief spike causes damage - not enough research has been done. There appears to also be a possibility that spikes have a damaging effect at lower thresholds for type 2 than type 1, partly from anecdotal discussions I've followed over the past four years and partly from the slight differences in results in studies like the DCCT and UKPDS. Let's face it - only type 2 have beta cells to lose anyway. Therefore I am swayed by the reports here, on Jenny's excellent web-page; there is enough evidence to convince me that staying under 8(140) is worth the effort - no matter when it occurs: Blood Sugar Levels and Organ Damage (lottadata.wixsite.com)

Of course, I tend to always aim a little tighter, so these days I set the level at 7(126) for my one-hour post-prandial maximum. What you do is up to you.

Cheers, Alan

Everything in Moderation - Except Laughter.