High Blood Sugar After Meals And What To Do About It


I will admit to having a bit of a diabetes crush on Gary Scheiner, MS, CDE, Type 1, and founder of Integrated Diabetes Services, LLC. And you know what? I’m not the only one. 

I recently saw Gary give a talk called “Strike the Spike” at the American Association of Diabetes Educators’ (AADE) 2013 conference to a room packed with diabetes educators. The point was to help CDEs understand why managing/avoiding post-meal blood glucose spikes is important – and to learn new techniques for how to do so. 

I was there because I am constantly struggling with post-meal spikes. I appear to digest food quickly and absorb insulin slowly — that’s why I’m on Symlin, which helps slow down the emptying of my stomach so I’ve got some chance of having my insulin start working by the time my food makes it to my blood. (I love my Symlin.) But I wanted to hear what other tips Gary might have, and what the responses might be. 

Gary started with a seemingly simple question: why should anyone care about post-prandial (i.e. post-meal) spikes? At first this question made me furrow my brow — I can’t imagine that anyone wouldn’t care about post-meal blood glucose spikes — but I guess that in some cases, health care providers stress the A1c average more than they do the swings in between. Anyway, the audience slowly warmed up, and reasons started pouring in, mostly having to do with complications. Gary nodded along, affirming each one. 

I was still struggling with the whole concept of not caring, and so I was caught off guard — as was most of the audience — when he pointed out a very important reason that post-prandial spikes matter, one that none of the certified diabetes educators in the room had pointed out (and, oddly, which I myself hadn’t even thought of): because they make patients feel like crap. 

I mean, think about it. As he pointed out, having high blood sugar: 

  • makes you tired
  • makes you irritable
  • makes it difficult to think and concentrate
  • impedes your athletic performance (strength, endurance, flexibility, etc — even if the high blood sugar is only for a short period of time)
  • irritability/mood shifts
  • increased hunger (ironic, isn’t it, that high blood sugar can make you want to eat more?)


“So imagine what it would be like to feel like that after every meal,” said Gary, going through some research studies showing results from studies showing how often people with Type 1 — even when they had decent A1cs — spent over 200 or 250 mg/dl an hour after eating. 

Just as I was absorbing the oddity of what had just happened — the entire room, myself included, missing that incredibly important and obvious conclusion — he pointed out something else. The chart we were looking at showed the patients’ blood glucose levels before and after each meal. In most cases, the patients’ glucose levels were very high (like, high 200s, even 300s) one hour after meals. But by the time they ate their next meal, they were relatively close to 120 mg/dl, despite not having given themselves any corrections. Gary’s point? If they had given themselves a correction, they would have gone low. 

I was incredibly affirmed by this point, since it’s something I, like many people on insulin, deal with all the freaking time:  rapid insulin just isn’t that rapid. Gary even made a joke about it: “It shouldn’t be allowed to be called ‘rapid,'” he said. “It should be called ‘rapider than regular.'” 

His point was that whereas naturally produced insulin can begin to affect your blood glucose within seconds, today’s “rapid” insulins take some 15 minutes before they start working at all. (For some people, myself included, they can take even longer.) It’s unrealistic, therefore, to expect that so-called rapid insulin taken at meal time will be able to work fast enough to catch your blood glucose spike from the food.

What’s more, no one really knows why hyperglycemia causes all these effects. Maybe it changes coagulation properties in the blood. Maybe it’s a result of oxidative stress or endothelial dysfunction. The question “makes the best scientific minds in the country cringe a bit and scrunch their eyebrows,” said Gary.  

So what’s a diabetic to do?

As Gary pointed out, there are two main approaches to this problem: either slow down your digestion (giving your insulin more time to catch up), or speed up your insulin (so that it better matches the spike caused by the food). Let’s start with the first approach. 

Techniques to slow down your digestion: 

  • Pay attention to the glycemic index (GI). Generally speaking, the higher a food scores on the glycemic index, the faster it will hit your blood sugar.
  • Combine high GI foods with foods that can help slow your digestion. These include high fiber foods and foods that have a fair amount of fat. Also worth noting: cold foods absorb more slowly than hot foods, and solids absorb more slowly than liquids. (This makes intuitive sense: your body has to warm things up and break them down before absorbing the nutrients, so if it’s cold and solid, it’ll take more time.)
  • Exercise. This does not have to be intense — a simple walk will do. Basically, anything that gets you moving will divert blood from your digestive system to your muscles. And the less blood you’re using to digest, the slower that digestion will be. 
  • Medications. His favorite was Symlin (which slows down the emptying of your stomach and also limits the amount of glucagon — and thus glucose — your body releases at mealtime, both of which help control spikes). He also mentioned alpha-glucosidase inhibitors and Dipeptidyl peptidase-4 inhibitors.
  • Try not to go into a meal low — having a low sugar before a meal can make your blood sugar spike even higher than normal after you eat.
  • Split your meal. In other words, take your full mealtime insulin dose, but only eat part of your meal. Wait fifteen minutes of so, and then eat the rest of it. Spacing it out like this (with your full bolus up front) will help give your insulin a chance to catch up. 
  • Eat your meal in a particular order. (No, this does not mean dessert first.) Gary said that there is research showing that eating (non-starchy) vegetables before eating starchy carbs seems to produce a gel matrix of sorts that slows down absorption. You also might want to try to have your highest carb meal for lunch, when you’re likely to have been the most active before and after (and so that you have ample time to correct).
  • Eat acid. (No, I didn’t say “take.”) This is a truly weird one, but apparently there is credible research suggesting that acidic foods (in the case of the study, 2 tbs of vinegar) slow down absorption and help reduce spiking after meals. You don’t need to eat straight vinegar, but things like tomatoes or lemons might be worth incorporating into meals. Incidentally, this may explain why my blood sugars appeared to be better when we received a jar of sauerkraut in our vegetable share box and I, struck by an odd, non-pregnancy-related desire to binge eat pickled cabbage, began eating it straight out of the jar — and noticed that my blood sugars seemed to be better than normal. 


Techniques to speed insulin action:

  • Take “rapid’ analog insulins — Novolog, Humalog, etc. (Many of us are likely on these already, but if you’re still doing Regular or trying to use NPH spikes to cover meals, you should consider switching.)
  • Pre-bolus. As Gary put it, “Giving insulin right before eating is like playing baseball and swinging after the ball’s in the catcher’s glove.” Experiment with taking your meal bolus 15 or 30 minutes before you actually eat. 
  • Heat the injection/infusion site. This may be a tricky one to figure out on your own, but basically, you want your circulation at your injection site to be as good as possible, and heat is one way to achieve this. Another is to exercise the muscles directly underneath your injection site — so if you inject in your stomach, try a couple sit-ups. if you inject in your hips or butt, try a flight or two of stairs, or some Jane Fonda-style leg lifts. I have done this myself and it works.
  • Similarly, try some post-meal exercise (interestingly, this both slows down digestion and speeds up insulin — among all its other benefits). According to Gary, even a 30-minute casual walk with your dog resulted in an average 30 mg/dl blood glucose reduction; people’s post-meal peak was 45% higher when they weren’t walking. (If you try this, make sure to bring glucose tablets and your glucometer with you, though, since, in my experience, sometimes this technique is TOO effective!)
  • Consider medication, including meglitinides.  


If you want to learn more, I suggest contacting Gary Scheiner directly (if you’re not convinced of his amazingness by now, I will point out that he was also recently awarded the honor of being AADE’s diabetes educator of the year). He practices in the Philadelphia area but also works with people from afar via phone or Skype, and specializes in intensive insulin therapy (MDIs, pumps, etc), as well as special populations/situations, including pregnancy and Type 1, and athletes with Type 1. He also is the author of Think Like a Pancreas: A Practical Guide to Managing Diabetes With Insulin. Whether you have Type 1, Type 2, gestational diabetes — or if you’re a CDE looking for new techniques to try with your patients — I really can’t recommend him highly enough. 

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9 years ago

Just now reading this piece–I can be a little slow–but found it absolutely great, full of excellent ideas. I’m a “Type 1.5” or “LADA” diabetic (which I refer to as “Type Weird”) and managing it is truly an experimental process. I’m grateful for new ways of thinking about it and ideas which can, perhaps, be modified and/or usefully combined. This was a keeper, and one for the printer, to be read again. Thank you, Catherine!

9 years ago

AWESOME article re Gary Guru – our CDE in 1996 three months after our then 13 yr old started pumping….also great to see Gary getting long overdue recognition for not only explaining diabetes 101 but doing so in a humorous & understandable way! 

9 years ago

I’ve had diabetes for over 20 years (and I’ve been on a pump for about 10 years) and I am JUST now getting the hang of this. I recently got my first {very good} sensor, and it has helped me see how these spikes happen! Also, I have stopped eating carb heavy meals, so I think that this has helped with those spikes as well! It’s so hard to know when to give an extra correction and when to just let it ride. I’m the same as you-my body takes a lot longer to use insulin, and it’s been really… Read more »

9 years ago

Great advice! We’ve been needing a kick in the butt to get back to our routine of taking a walk after dinner. This will help.

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