🍽️ Warsaw Method Calculator

Balance insulin for carbohydrates, fat, and protein using the Warsaw School method and fat-protein units (FPU).

The Warsaw method converts calories from fat and protein into “fat-protein units.” Each FPU represents roughly the insulin needed for 10 grams of carbohydrate, typically delivered as a delayed/extended bolus for high-fat meals.

Also called insulin-to-carb ratio. If unknown, use your standard meal ratio or consult your diabetes educator.

Many clinicians ignore fat-protein insulin if FPUs are below 0.5. Adjust the threshold per your diabetes team’s advice.

Warsaw method: 1 FPU = 100 kcal from fat + protein ≈ insulin for 10 g carbohydrate (delivered as extended bolus).

How to Use This Calculator

1

Count carbs, protein, and fat

Determine grams of carbohydrate, protein, and fat in the meal. Accurate nutrition labels or weighed portions give the best results.

2

Enter your carb ratio

Use the insulin-to-carb ratio provided by your diabetes team. Adjust the FPU threshold if your clinician recommends ignoring small amounts of fat/protein.

3

Deliver the bolus thoughtfully

Combine the immediate carb bolus with an extended bolus for FPUs if recommended. Monitor glucose trends and adjust with your healthcare provider.

Formula

The Warsaw method (also called the Warsaw School or Polish FPU method) uses the following steps:

  • Caloric load from fat and protein = (Protein grams × 4) + (Fat grams × 9)
  • Fat-Protein Units (FPU) = calories á 100
  • Each FPU is treated with insulin equivalent to 10 g carbohydrate using the individual’s carb ratio
  • Total insulin = carb insulin + FPU insulin

Pump therapy often pairs FPUs with extended bolus delivery over 3-8 hours, matching the slower glucose rise from fat and protein metabolism.

Full Description

High-fat or high-protein meals can trigger prolonged postprandial hyperglycaemia despite accurate carbohydrate counting. The Warsaw method extends bolus dosing by converting calories from fat and protein into supplemental insulin, smoothing late glucose rises, especially in insulin pump users.

Each 100 kcal from fat/protein equals one FPU. Because fat and protein are digested slowly, FPU insulin is typically delivered as a dual or extended bolus. For injections, some clinicians split the FPU insulin and deliver a portion immediately and the remainder 1-2 hours later.

The Warsaw method requires individualisation. Sensitivity to fat-protein insulin varies with activity, gastric motility, pregnancy, age, and insulin action profiles. Keep detailed glucose logs and collaborate closely with a diabetes educator or endocrinologist when adopting this method.

Frequently Asked Questions

How does Warsaw differ from the Pankowska or Dublin method?

The Warsaw method equates 1 FPU to 10 g carbohydrate. Other methods use different calorie-to-insulin conversions or timing rules. Follow the protocol endorsed by your care team.

Do I always need FPU insulin?

No. Many clinicians recommend ignoring FPUs below 0.5 or when meals contain minimal fat/protein. Adjust thresholds based on personal experience and professional guidance.

Can people on injections use the Warsaw method?

Yes, but timing is challenging. Some split boluses or use intermediate-acting insulin. Insulin pumps make extended delivery easier.

How do I adjust for exercise or alcohol?

Exercise and alcohol can lower glucose hours later. Coordinate FPU boluses with activity plans and monitor closely to avoid hypoglycaemia.

Is Warsaw method safe for children?

Many paediatric diabetes centres in Poland use FPU calculations, but dosing must be tailored by paediatric endocrinology teams. Never alter a child’s insulin regimen without professional oversight.