This section is for everyone. If you are managing successfully on your pump you may skip this section and proceed to the How To: Cover a Strict Low Carb, Moderate Low Carb, and High Carb Diet with Insulin section.
Well, of course, you can’t really change your pen into a pump. But what you can do is look at why pumpers often get better meal coverage than the injectors.
Pumpers can do several things with their pumps to get better meal coverage.
They can pump in several units at once – an immediate bolus.
They can give the dose over a few hours – an extended bolus.
They can programme the pump to give two smaller boluses within a short time of each other – dual wave bolus.
Fortunately you can get the same results with your pens and vials.
Pumpers are told that to avoid a lump of insulin under the skin they need to pump 5 units or less at an immediate bolus whether for correction doses or for covering meals. They may go on to cover the meal with a dual wave or extended bolus if they need more insulin than this for that meal.
The absence of the lump of insulin under the skin makes its absorption much more predictable. Did you know that 70 units of insulin injected under the skin takes a week to fully absorb?
Dr Bernstein has found that 7 units injected at once is the absolute highest amount of insulin per shot that will ensure accurate enough absorption of that insulin. Otherwise the insulin you think is going to cover that meal won’t work as well as you expect and it is likely to release when you don’t really want it to.
Now the 7 units per shot tip is something that often fills newcomers with dread. They say things like, “You mean I’ll need four jags to cover one meal! You have got to be kidding!”
Why is this? It’s not just because they can’t divide by 7. It’s not just because they object to the slightly increased time the injection procedure will take. It’s because up until now they have been having injections that are really quite unpleasant and often painful. They also worry about the lipoatrophy at their injection sites. Does this mean more of these?
The answer is no. Not only do the smaller amounts give you an insulin that “does what it says on the tin”. They give you a lot less discomfort per shot and virtually no lipoatrophy at all.
You will have noticed that I almost expect that you will be eating a high carb/low fat diet right now. Let’s face it, you are only doing what you have been told to do by your doctors and dieticians. As you get further into the low carb way of eating you will find that you need less and less insulin to cover your meals. And that means many fewer injections as time goes on.
When someone goes from a multiple daily injection regime to a pump they need to cut down on the total daily amount of insulin they go on with the pump. This is usually a decrease of 20%. This is because the slow leakage of insulin under the skin is more efficient at getting the insulin into the body. Its not just sitting in a big lump doing nothing any more.
The 7 unit per shot system is not quite as efficient as a pump but gets you results that can be pretty close. I therefore recommend that you also reduce your bolus amounts by 15% to start with. You do this for your current basals as well as for your current meal boluses. This would not apply if you inject 7 units or less at that time normally of course.
Dual wave bolusing can be done by two or more injections to cover a meal of the more slowly digesting type such as meaty dishes, pizza, and pasta with creamy sauces. You simply need to remember to give the second or third jag at the time you planned.
Fortunately there are different durations of insulins that can be used that can give you the same effect as an extended bolus.
Most insulin users have been put on rapid acting analogues for meals. Novorapid and Humalog. These peak at about 70 minutes and last about 3 and a half hours with a tail to about 5. What the usual blurb says is that they cover “most meals” and so this is all you need.
Before analogues were invented however the older regular insulins were used to cover meals. These peak at about 2 and a half hours and last 5 hours with a tail to about 8 hours. What the usual blurb says is that these take longer to work and are less convenient than analogues to cover meals.
These characteristics are however just what you want to cover higher protein, higher fat, and more low glycaemic carbs. Its rather wonderful in fact.
When you give these regular insulins on their own to cover carb you need to remember two things. Firstly they do take longer to work so you need to inject them optimally 45 minutes before eating that carb. 30 minutes will do but is not optimal. The second thing to remember is that these are less potent insulins and you need to give a third more of them than with analogues for the same amount of carb. Actrapid would cover 8g of carb compared to one unit of humalog that would cover 12g.
When you use these insulins to cover protein and more slowly digesting meals the fact that they take longer to start working becomes an advantage and you can get on with injections optimally 15 minutes before a meal. Just before you eat will often do.
Quick Quiz:
1.The same amount of insulin to cover the same high carb meal at the same time of day can have a varied effect on your blood sugars by:
a 5%
b 15%
c 30%
d 90%
2.Insulin effect predictability can be improved by one of these…
a Keeping injections to 7 units or less.
b Having regular snacks.
c Having a low fat/high carbohydrate diet.
d Taking plenty of aerobic exercise.
Have you got it?
1. C is correct. The Joslin Institute have put it as high as 30-50%.
2. A is correct. The other options are likely to make blood sugar control more difficult.
Reference Info:
- Acknowledgements: Dr. Bernstein’s Diabetes Solution and Dr Gary Scheiner’s Think Like a Pancreas.
- The presentation by Dr. Katharine Morrison How you can achieve normal blood sugars with diet and insulin is a good summary of the points that you need to know.
Where to Next?
Please now continue to the How To: Cover a Strict Low Carb, Moderate Low Carb, and High Carb Diet with Insulin section.