Takeaways causing blood glucose spikes? Here's what I do.

Updated: Feb 21

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The information in this article is based on my own knowledge and experience. Please consult your healthcare professionals before making any changes to your usual plan.

Carbohydrates, proteins and fats are regarded as macronutrients. This is a term used to describe a nutrient which is used by the body in order to obtain energy (calories). Macronutrients are essential for the body to function properly and must be obtained through diet. Each of these macronutrients have important functions in the body.


Carbohydrates are classed as simple or complex. The main difference between the two is how quickly the sugar is absorbed and digested into the blood. When digested, carbohydrates are broken down into sugars. Simple carbohydrates contain only one or two sugars and so therefore are digested and absorbed by the body very quickly.

Complex carbohydrates on the other hand, have three or more sugars and can be referred to as ‘starchy foods’. If you’ve ever wondered why children go a bit hyper after having sugary foods, it’s caused by the quicker rate of sugar absorption which leads to bursts of energy.

Simple carbohydrates:

  • Sweets

  • Fizzy drinks (regular)

  • Fruit juices

Complex carbohydrates:

  • Bread

  • Pasta

  • Oats

Carbohydrates and blood glucose

It’s quite obvious that if you neck a bottle of regular coke or eat a family pack of tangfastics, your blood glucose is going to hit the roof. It’s why we use small amounts of sugary carbohydrates to raise our glucose when we’re in hypo or about to do strenuous exercise.

They absorb quickly into our blood and increase its concentration of glucose. Complex carbohydrates on the other hand don’t work as fast. Don’t get me wrong, if you eat an entire loaf of bread, you’ll still see your blood glucose on a steady rise, but it just won’t be as fast as if you downed a bottle of coke. Sugars still have the same effect on your blood glucose, they just increase it at different speeds.

Fats & Carbohydrates

How to stop a delayed spike…

After many years of trial and error, I can successfully say I have finally cracked how to inject for fatty foods such as takeaways and pizza. If you’re newly diabetic, you’ll soon discover the mystery of hyperglycaemia several hours after eating these types of foods. It’s a phenomenon which has led to me rising from the dead at 4am with a sandpaper tongue and a shrivelling body from dehydration. I would test my blood sugar in a haze and find the reading to be between 16 mmol/L and 28 mmol/L.

I was completely clueless about why this was happening. I’d have the pizza, pasta or takeaway at around 7-8pm, inject a shockingly large amount of bolus (up to 20 units) and go to bed on a blood sugar of 5.4 mmol/L.

Arrogance would consume me as I whole heartedly believed my carbohydrate counting was beyond perfect. This was always followed by a fit of rage when I’d have to drag myself out of bed to avoid wetting it only hours later.

I decided to do some research on why fatty foods was causing this annoying situation time and time again. What I found was that foods high in fats, such as pizza or takeaways delay stomach emptying and increase insulin resistance. In the end, this ultimately results in a delayed rise in blood glucose hours after you’ve eaten.

Take this example. Below is a snapshot of my glucose over a six-hour time period following eating an Indian takeaway. I had my food at around 7pm before going to bed on 5.0 mmol/L at around 10pm.

As you can see my blood glucose steadily increased for hours over the night, reaching almost 20 mmol/L in the early hours of the next morning. My body woke me up and I corrected to bring my glucose back down to the normal range.

How to stop a delayed spike…

Injecting with pens is slightly more complicated than on a pump, especially when it comes to spreading the bolus out over a long period of time. However, if you’re on a pump with muti-wave abilities, here’s what I do to avoid those night time spikes.

My golden method (based on my ratio's)

  1. Immediately before or after eating the food, I inject half of the total bolus dose. For example, If a pizza came to 15 units of insulin, I’d inject 7.5 units straight away. If you’re on a pump, I'd set the remaining 7.5 units to trickle out over around 5 hours through the use of multi-wave/dual wave.

  2. When I was on pens, I injected the other half around 3-4 hours later.

  3. Once the entire bolus has been administered (first and second half), I test blood glucose to see where I stand.

  4. I tell my insulin pump that I'm consuming half the original carbohydrates for the meal. For example, in this case I’d tell the pump I’m eating 75g of carbohydrate (equates to 7.5 units of insulin - half the original dose from the pizza). Set the bolus to multi-wave over a 4-5 hour period. This way the 7.5 units of insulin will administer over night, buffering my blood glucose.

  5. When I was on pens I never did the third and final dose before bed. Only since starting a pump have I had more flexibility in experimenting with my insulin.

Total insulin:

1.5 X total amount of insulin required to cover the food

My golden results…

With this strategy, I have managed to maintain stable blood glucose over night after eating a fatty meal. Below is another one of my blood glucose snapshots after using this method of mine.

Note: I am not a healthcare professional or a dietician. The information in this article is based on my knowledge and experience. This is not designed to be a substitute for the advice your healthcare team provide you with.

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