After the success of our first Masterclass with Prof. David Segal, we had to have another one. Here are all the highlights (and a recording if you want to watch it!)
The Masterclass was broadly about how to interpret and improve glucose reports – that is, how to improve blood glucose control! Glucose reports are the detailed reports you get from your FreeStyle Libre or CGM, that give a picture of what your blood glucose has been doing.
We asked Prof. Segal for his top five tips for people living with Type 1 diabetes. Here goes!

1. Timing
Timing your insulin is so important – if you take it at the right time, you can see much flatter lines in your Libre graphs. The general advice is to inject about 30 minutes before you eat, but that depends on the rate and direction your blood sugar is going – if it’s heading down towards a hypo, you don’t need to wait or you’ll go low. If your blood sugar is high or the arrow on your Libre is pointing up, you’ll need to wait till it starts coming down before you eat. The best approach is to inject and then scan your FreeStyle Libre to see when your blood sugar graph starts flattening or starting to dip down, then eat.
2. Eat less carbs
In general, Prof. Segal recommends eating less carbs. This depends how active you are – if you are more active you can get away with more carbs, but in general he advises 90g to 120g a day. That’s 6 to 8 portions of carbs a day (here is how to carb count, and a list of carb portion sizes).
3. Site migration rather than site rotation
It’s really important to rotate your injection sites every day, so that you don’t inject into the same spot and develop lipohypertrophy. (Here’s all the info you need about lipohypertrophy.) But Prof. Segal recommends site migration rather than site rotation: moving all your injection sites to one site for the day (for example, left thigh) and moving to another site the next day (for example, right thigh).
He explained that because insulin is a hormone that grows fat, injecting into the same site will increase the growth of a fat lump under the skin – which can reduce the insulin dose by up to 25%!
The skin is 3mm thick all over the body, regardless of an individual’s age or weight. You can inject anywhere in the body, but avoid muscle because insulin will absorb quicker in muscles because the blood flow is faster and it will bruise and be painful.
Good sites are the butt, thighs and tummy. It also depends on what activities you do after injecting, if you are an athlete or exercise a lot, then avoid the thighs because they will absorb much quicker and faster.
4. Glycaemic impact
Before you can understand glycaemic impact, it’s important to understand the Glycaemic Index: how quickly a carb breaks down to get absorbed. This is variable from person to person, but you can read up on the basics about low GI (Glycaemic Index) here.
Then there’s the glycaemic load: how quickly food gets into your blood stream multiplied by the amount you ate.
And finally, glycaemic impact: which includes all carbs, proteins and other things that can make your blood glucose go up – stress, high intensity exercise, hormones, etc.
So what can you do about glycaemic impact?
- Inject earlier (see point number 1!)
- Pay attention to your food order: eat your protein and vegetables first, then your carbs so that their effect on blood glucose is delayed.
- Put vinegar on your food, or have one glass of diabetes-friendly alcohol before you eat, as alcohol can slow down the rate of absorption of carbs. Here’s some advice on alcohol and diabetes.
“If you can spend less time being variable, then you spend more time with normal blood sugar.”
Prof. David Segal
5. Routine, Routine, Routine
Prof. Segal’s fifth and final tip for Type 1s is to stick to a routine as much as possible. Check, analyse and adjust. Do things that work and throw away those that don’t.
The goal is to improve your glucose variability (the differences in your blood glucose – displayed as a percentage on LibreView). Opportunities for improving variability include fixing the five points above: fixing the timing of injections, routine and site changes.
But then we kept getting more and more questions, and the great tips kept coming!
How to fix consistent blood sugar spikes after breakfast
If you’re struggling with consistent blood sugar spikes after breakfast, limit your carbs significantly. Consider intermittent fasting, if you aren’t hungry first thing in the morning.
Reasons for a blood sugar spike
It’s likely that your blood sugar spiked for one of the following reasons:
- Timing of your insulin injection.
- Change in routine
- Injecting in the wrong site (one you’ve over-used)
- Portion size or food choice
- Glycaemic impact – could it be stress, the weather, hormones, lack of sleep?
“Eat breakfast like a pauper – something simple, the same thing every day, and limit your carbs.
Prof. David Segal
Eat lunch like a king – experiment with new foods and increased carbs.
Eat dinner like a prince – something simple with reduced carbs for steady overnight blood sugar.”
How to fix low blood sugar
Sweets (jelly sweets) are a good choice. One equation to work on is 0.3g per kg to fix a low, but it’s a good idea to do it slow and measured: check after 10 minutes and re-treat (eat more sweets) if it’s still low or not changing. If it stabilises, just wait. This is obviously much easier to do when you have a flash glucose monitor like the FreeStyle Libre to show you a graph of which direction your blood sugar is going in!
Low blood sugar before breakfast is generally a matter of your night-time (long-acting) insulin.
If you go low before a meal, fix the low blood sugar with a small amount of glucose and still inject before the meal – don’t eat your meal to correct your low.
Try to figure out why you went low, so that you don’t repeat the same behaviour consistently.
How to fix the dawn effect:
It can be difficult to fix the dawn effect (also known as ‘feet on the floor’ syndrome – when your blood sugar starts rising as soon as you wake up). Moving long-acting insulin later at night can help (as can moving to an ultra long-acting insulin). Otherwise, it’s important to take a small dose of fast-acting insulin when you wake up, and another small dose before breakfast.
Photo by Scott Graham on Unsplash
What to read next
How to interpret your glucose reports: highlights from a Masterclass: Endocrinologist, Prof. David Segal explains how to interpret your glucose reports
What is a CGM? Flash glucose monitoring and CGM: Not sure what the difference is, or what these words mean? Read this article.
Everything you need to know about the FreeStyle Libre: We gathered all your questions and answered them – here’s all you need to know about the Libre.
The low carb diabetic pantry: We asked a dietician how to stock your kitchen for low carb cooking – here’s what she said.
Discover more from South Africans with Diabetes
Subscribe to get the latest posts sent to your email.
Be First to Comment