Overview
This page gives you three practical options for tackling high-fat meals with carbs — the meals that look “fine” at first, then hit you 2–4 hours later with a second rise.
Examples: full English breakfast; buttery pancakes with maple syrup; thick cheese on toast; cheesy pizza; fish and chips; fast-food burger and chips; lasagne with chips and garlic bread.
There are more than three ways to do this. These are the approaches that consistently work in the real world for the people I teach — and they give you a clean starting structure to experiment from.
The detail
What happens after a high-fat meal?
High-fat meals often create a delayed second rise. You can look “sorted” for the first 1–2 hours… then glucose climbs later and needs much more insulin than you expected.
Why does glucose rise hours later?
Two things tend to collide:
- Delayed digestion (fat slows gastric emptying), so carbohydrate arrives later.
- Temporary insulin resistance after high-fat intake — the “DAG effect” described by Shulman and colleagues.
The Drive: Episode 140 – Gerald Shulman’s deep dive into insulin resistance.
Here’s the mechanism in one image:
A necessary warning
It’s possible to “win” against high-fat meals by using a lot of extra insulin. But that often means running high insulin levels in the bloodstream more of the time — which is not how physiology is designed to work (people without type 1 diabetes run high insulin mainly in the portal vein, not the systemic circulation).
So yes: you can manage takeaways with enough insulin. But if high-fat meals become frequent, it’s worth tracking the bigger picture — especially total daily dose and units per kilogram — alongside glucose metrics.
Use this as your reality check: Measuring success.
Option 1: split and extend the insulin
This is the default approach: you add extra insulin and spread it out to cover the delayed rise.
How much extra, and how do I spread it out?
Based on the research and the longer teaching in the detailed module, here is a safe way to experiment without guessing wildly.
- A meal is only “high-fat enough” to need this approach if your CGM has shown the delayed rise before. That’s the entry criterion. The Glucose Never Lies.
- Next time you eat that same meal:
- Count carbs and calculate your usual mealtime dose.
- Increase the dose by 25% to start (simple maths: dose × 1.25).
- Split the total dose roughly 50/50:
- Pump: 50% up front, 50% extended over 2 hours (adjust the duration based on your CGM pattern).
- Injections: 50% before the meal, 50% about 1 hour after.
- If possible: add ~15 minutes of moderate activity at around 2 hours after eating.
- If glucose is still high 6 hours after the meal, next time increase the extra insulin by another 25% and repeat.
Be prepared to need more than 25% extra. Research and clinical reality often land nearer ~50% extra on average for classic high-fat + carb meals — and some meals (pizza…) can require more.
Option 2: use activity as an insulin sensitiser
This option is simple but demanding: be very active after the meal to:
- Make insulin stronger and last longer.
- Open “side doors” into cells that don’t require insulin.
- Burn up DAG inside the cell for energy so insulin signalling works again.
Companion listen: Activity Snacking podcast.
The result of that “triple threat” looks like this:
Option 3: accept the rise, then use GAME
If the meal is going to do what it does, you can choose a controlled response: set your high alarm and use GAME to stop the high without stacking repeated corrections.
What’s next
If you want all three meal types on one page, use the Mealtime insulin infographic.
Mealtime insulin / related content
Navigate as you need.
- Mealtime insulin guide (hub)
- High-carbohydrate meals
- Balanced meals
- High-fat meals
- Mealtime insulin infographic
