Understanding why you might have high blood glucose after eating is a hurdle that others without diabetes might not need to think about.
However, once you have that knowledge under your belt, you will have the confidence to know that you control your diabetes – not the other way round!
To get control of that blood sugar level after eating, we should first look at what happens with the body. From this we can get an understanding of different approaches to handling that after-meal spike, as well as some often overlooked aspects.
Postprandial Blood Sugar and the Body
If you have diabetes, you are probably already very aware that your body doesn’t naturally transport glucose to the cells. But let’s do a quick run-through, so we’re certain we know what the body is up to.
Easily plot your after-meal spike with HDA's Diabetes Dashboard. Try it on our app at Google Play or the App Store!
Quite simply, blood glucose – or, more informally, blood sugar – rises when food is consumed because food is converted into glucose. Specifically, carbohydrates are converted into glucose. So, eating results in more glucose in the bloodstream. This is called postprandial blood glucose/sugar. (Post means after and prandial means meal. Essentially: after-meal blood sugar.)
In those without diabetes, postprandial blood sugar is not a great concern because the glucose doesn’t stick around in the blood. Instead, the pancreas releases insulin whose job it is to allow glucose to enter the cells to be used as energy. This is done automatically and continuously.
Of course, those with diabetes are either partially or completely unable to produce enough insulin, or are less sensitive to the effects of insulin. While insulin injections or certain drugs remedy this situation, they do not have the benefit of the instant and continuous quality of a fully-functioning pancreas. As a result, it is typical for those with diabetes to have blood sugar spikes after a meal. Find the target postprandial blood sugar levels in the image below.
These numbers are recommendations from both the American Diabetes Association (which gives general numbers for both type 1 and type 2 diabetes) and the National Institute for Clinical Excellence (which gives different numbers for type 1 and type 2 diabetes). While these are general target numbers, a doctor will recommend personalised numbers for a person with diabetes.
Measuring Carbs and Insulin for Blood Sugar Level After Eating
Reaching those target levels is definitely easier said than done. To get greater control of blood sugar after eating, we should think about it in a comprehensive way. First, let’s look at food in relation to insulin.
Food is where it all begins; make sure you are eating fibrous and nutritious kinds of carbohydrates. Examples of food containing the kind of carbohydrates which are beneficial are whole-grain bread or pasta, legumes like chickpeas and lentils, grapefruit, pears, apples, and potatoes.
But how does a person with diabetes control what their body does with that food? Getting the right amount of insulin is important. While insulin injections are usually a matter for those with type 1 diabetes, many with type 2 also benefit from insulin treatment. Understanding insulin injections is helpful for all people with diabetes, and people in their support network.
The insulin dosage taken at a mealtime is called a bolus. The calculations for the bolus vary from person to person – this is where a doctor will help. The insulin to carbohydrate ratio will be established. This will help you understand how many grams of carbohydrates are covered by one unit of rapid-acting insulin.
Hedia’s page about our app, “Carb Calculator and Diabetes“ gives explanations for these calculations. Find a snippet of that page below for the calculation of the 500 rule.
The 500 rule is a standard way of calculating your insulin to carb ratio which takes into account the total daily dose. The total daily dose is the total amount of insulin taken in a day including: a combination of long-acting and fast-acting insulin.
Even seasoned carbohydrate counters will know that the calculations are never that straight-forward. Some guesstimations can be off. Sometimes you forget what you ate. Sometimes the roller coaster ride came out of nowhere and you have no idea why
This is where I really believe that Hedia’s insulin calculator can help with dealing with that postprandial spike. Hedia assists with the three areas of blood sugar after eating:
1) Knowing what carbohydrates you’ve eaten. While reading food labels will give you the information you need, this can be tedious or sometimes not even an option. Hedia’s food database has over 1500 food items: get the information and let Hedia do the carb counting for you!
2) Remembering what you’ve eaten. Use the app’s diabetes logbook to keep track of food.
3) Knowing how much to inject. Based on the information from the food database (and other factors, such as exercise, insulin on board (IOB), and insulin to carb ratio), the app will suggest an insulin dosage.
Different Approaches to Managing Blood Sugar After Eating
Each person’s body is different, and responds to insulin in a different way. There is no one-size-fits-all insulin treatment.
So, even after you’ve counted your carbs and figured out how much to inject, there is still another way to influence your blood sugar level after eating. Namely, try different methods and time-periods for injecting.
The common method is to inject before eating. Rapid-acting insulin requires injections 5-15 minutes before eating. Those minutes are the time it takes for insulin to enter the bloodstream. That way, your body will be ready for digestion once eating has begun.
After entering the bloodstream, rapid-acting insulin peaks after 1 hour – this is when it is most effective at lowering the blood sugar level after eating. This insulin will remain effective for 2-4 hours in the body. Find out whether those minutes and hours work best for you by trial-and-error and consulting with a doctor.
If not, splitting the bolus is another route to more efficient insulin treatment. This is especially useful if eating fatty food, such as takeaway pizza or curry. This means taking a portion of the insulin before eating, and a portion after eating. Again, this is trial-and-error. Experiment and speak to a doctor.
It’s always good for a person with diabetes to know what is going on with their body. So, when trying different methods, remember to keep testing. And keep testing even when sticking to the same routine. This is especially the case after a meal: you need to know how those blood sugar spikes are doing. Test the blood sugar between 1 and 2 hours after eating to know what the insulin has been up to.
You can adjust your insulin treatment according to the numbers you get from your blood glucose meter. Keep track of the spikes on the Hedia app by transferring blood glucose measurements wirelessly to the logbook with your NFC or Bluetooth glucose monitor. This way, you can easily look for trends with a doctor.
Also, if you have access to a continuous glucose monitor (CGM), take advantage of it. The CGM is precisely for the purpose of more frequent testing over time, rather than a single test with the traditional lancet and test strips. So, you can keep testing without getting a full constellation on your fingers from all the finger-pricking.
Don’t feel Disheartened
If, after all the above has been considered, remember to not be disheartened when the blood sugar after eating is still haywire.
There are other factors which can make the blood sugar numbers surprising. Three common overlooked aspects to bear in mind:
1) Stress decreases insulin sensitivity
2) Exercise increases insulin sensitivity. Exercise can influence insulin sensitivity for up to two days! Find out more at “Does Exercise Lower Blood Sugar?“.
3) Don’t forget how long the insulin remains active in the body after injecting. If you have a snack a few hours after eating, then you might need to inject slightly differently, depending on the blood sugar.
These aspects of life do not need to feel out of your control. If you know when you will eat or exercise, you can plan in advance. Consider taking half-units if you feel that your insulin sensitivity is changing. Meanwhile, try and identify what causes stress to avoid it. Learn more about the impacts of stress by checking out the articles under 'Stress & Diabetes' on the Help Centre.