Carbohydrate counting: the skill that makes bolus insulin usable

Overview

This might surprise you: despite being a diabetes dietitian, this is one of the shortest pages on the site. That’s because the real teaching lives in the Interactive carb-counting guide. Once you’ve worked through it, carb counting becomes straightforward — and you’ll be able to calculate your bolus insulin accurately enough to act, then refine using real-world CGM patterns.

Prefer video? Here you go:

The detail

What the interactive guide gives you

The Interactive carb counting guide is packed with videos, worked examples, and short tests. Complete that, and you’ll be able to:

• work out the carbohydrate content of any meal,
• calculate your meal bolus,
• then adjust intelligently using CGM trends and experience.

Here’s a taster of what’s inside.

Basic table of what to count

How flexible can you be with carbs?

If some of the carb amounts in the guide feel high, that’s normal. The range is wide — from very low carb through to high carb — and the point is competence across the spectrum, not a single “correct” intake.

GNL has explored this directly, including a 120-day low-to-high carb experiment. Many people start by capping carbs because it makes glucose management easier.

With Dynamic Glucose Management and a strong grasp of FAST movers between meals, you can often be more liberal without sacrificing control. The limiting factor isn’t willpower — it’s whether the foundations and between-meal strategy are in place.

Working out carbs in real life

Using Carbs & Cals resources

Reading a food label

Using labels expressed per 100 g

My honest take on carb counting

The pros

• It helps you calculate a meal bolus that is close-ish to the glucose you’re about to absorb.
• It’s simple and teachable to family members.
• Children can get involved in insulin decisions early, which builds skill and confidence over time.

The cons

• The key message of three balanced meals often gets replaced by “eat what you like, just count and dose” — which is reductive and usually backfires.
• It’s too simplistic on its own.
• It creates false certainty: you can count perfectly and still get it wrong.
• It ignores the insulin-resistance impact of high-fat meals and other factors covered in the Mealtime Insulin Guide.
• It nudges people towards processed food because it’s easy to count, not because it’s good for them.

Rant over.

What’s next

Next step: Three balanced meals.

Foundations / related content

The order shown below is recommended, but navigate as you see fit.

• What is Diabetes?
• Continuous glucose monitoring (CGM)
• Basal insulin
• Bolus insulin
• Correction insulin
• Carbohydrate counting
• Three balanced meals
• Hypoglycaemia
• Measuring success

References

• Interactive carb counting guide (PDF)
• Bolus insulin
• Mealtime Insulin Guide
• Dynamic Glucose Management
• 120-day low-to-high carb experiment