NfE calculator cat: Calculate carbohydrates in cat food
The NfE value is a mathematical approximation for carbohydrates in cat food. Enter the crude protein, crude fat, crude ash, crude fiber and moisture from the label. The calculator shows you the NfE value in the original substance and in the dry substance so that you can compare wet food and dry food more fairly.
What does NfE mean for cat food?
NfE stands for nitrogen-free extractives. In everyday life, the NfE value is used as an approximation for the carbohydrates in the feed, especially for soluble sugars, starch and other calculated residual components. It is not measured directly on the label, but is calculated from the analytical components.
Important: A low NfE value is a helpful indication, but not a complete judgment of quality. Protein quality, fat content, minerals, energy content, acceptability and whether it is a complete feed that meets requirements also remain decisive.
What values do you need from the label?
- Crude protein
- Crude fat or fat content
- Crude ash
- Crude fiber
- Moisture
You will find this information in the analytical constituents. If the moisture is missing, the calculation becomes more uncertain. It is often significantly higher for wet food than for dry food; this is precisely why the subsequent conversion to dry matter is so important.
NfE formula: Calculate carbohydrates in cat food
Sample calculation
A wet feed has 10 % crude protein, 5 % crude fat, 2 % crude ash, 0.5 % crude fiber and 82 % moisture. In the original substance, this results in 0.5 % NfE. Because only 18 % of the feed is dry matter, this corresponds to 2.8 % NfE in the dry matter.
Why dry matter is crucial
The values on the label are usually in the original substance, i.e. including water. As a result, wet food often looks less nutritious than dry food at first glance. Only the conversion to dry matter removes the water content and makes food types with different moisture levels more comparable.
The US FDA also explains this logic for the comparison of wet and dry food: nutrient values should be converted to dry matter if the moisture content is very different, otherwise you are comparing water content instead of nutrient content.
What NfE value is good for cats?
For cats, the NfE value in the dry matter is of particular interest. The following values are practical orientation ranges, not medical limit values:
| NfE in dry matter | Classification |
|---|---|
| 0-2 % | very low |
| up to 6 % | low |
| up to 10 % | moderate |
| over 10 % | more closely, especially for Diabetes, overweight or very carbohydrate-conscious feeding |
Cats are nutritionally specialized in animal nutrients. According to the Merck Veterinary Manual, carbohydrates are not considered essential nutrients for adult, non-reproducing dogs and cats. At the same time, cats can utilize appropriately processed starch. A sober classification is therefore useful: fewer carbohydrates can be a sign of quality, but is no substitute for looking at the whole food.
NfE for diabetes or obesity
With diabetic cats a high-protein, low-carbohydrate diet is often recommended. In addition to insulin therapy, the Merck Veterinary Manual recommends a high-protein, low-carbohydrate diet for cats with diabetes; Wet food is often preferred.
Please do not change a diabetic cat's food on your own if they are on insulin or diabetes medication. Changing to a lower carbohydrate food can alter blood sugar and insulin requirements and should be discussed with your veterinary practice.
Common errors in the NfE calculation
- Confuse original substance with dry substance: The dry matter is almost always more meaningful for comparison.
- Appreciate humidity: This may be necessary with dry food, but makes the result less accurate.
- Overinterpret negative values: Negative NfE values usually result from rounding or declaration inaccuracies.
- Equate grain-free with low-carb: Potato, pea, sweet potato or other sources of starch can also increase NfE.
- Use NfE as the sole quality criterion: A food with a low NfE must also suit the cat as a whole.
Find the right cat food
If you want to compare a food after calculating, start at Wet cat food, Dry cat food or the selection for carbohydrate-conscious feeding. For many products, you can find the analytical ingredients directly on the product page and check the NfE value.
Tested examples from the store
| Product | NfE in dry matter |
|---|---|
| Lucky-Kitty Beef - 200 g | 0 % |
| Lucky Lou POULTRY with parsnips - 300 g | 8.5 % |
| THE GOODSTUFF Duck & Chicken - 200 g | 10 % |
| THE GOODSTUFF Chicken with herring - 200 g | 5.71 % |
| TUNDRA Salmon & Duck - 200 g | 6.5 % |
| MjAMjAM Juicy Chicken & Wild Salmon - 125 g | 4.76 % |
Important: These examples are not medical recommendations. In the case of diabetes, insulin therapy, severe obesity, kidney problems or regular medication, please consult your veterinary practice about a change of food.
-
Diabetics Mono AdultLucky-Kitty Beef - 200 g
CHF 4.30CHF 21.50 / kg -
2 Grössen Diabetics AdultLucky Lou POULTRY with parsnips - 300 g
CHF 2.95CHF 9.83 / kg -
AdultTHE GOODSTUFF Duck & Chicken - 200 g
CHF 2.70CHF 13.50 / kg -
2 Grössen Diabetics AdultTHE GOODSTUFF Chicken with herring - 200 g
CHF 2.70CHF 13.50 / kg -
2 Grössen Diabetics AdultTUNDRA Salmon & Duck - 200 g
CHF 2.40CHF 12.00 / kg -
4 Grössen Diabetics AdultMjAMjAM Juicy chicken & wild salmon - 125 g
CHF 2.00CHF 16.00 / kg
FAQ on the NfE value for cat food
What is the NfE value for cat food?
The NfE value is a mathematical approximation for carbohydrates. It is calculated from 100 minus crude protein, crude fat, crude ash, crude fiber and moisture.
Why is the carbohydrate content not stated directly on the packaging?
Feed labels typically state analytical components such as crude protein, crude fat, crude fiber and moisture. Carbohydrates or NfE are usually not declared separately and are therefore approximated by calculation.
Is a low NfE value automatically good cat food?
No. A low NfE value can be a good sign, but it says nothing about protein quality, mineral balance, calories, digestibility or meeting requirements.
What to do if there is a lack of moisture or crude ash?
The calculation is then less accurate. For a rough guide, you can work with assumptions, but for medical decisions you should obtain manufacturer information or consult a vet.
Is NfE important for diabetic cats?
Yes, the carbohydrate content can play an important role in diabetes. Nevertheless, the NfE value should not be considered in isolation. Feed changes in diabetes belong in the veterinary practice, especially if insulin is involved.
Sources and further information
- FDA: Complete and Balanced Pet Food
- Merck Veterinary Manual: Nutritional Requirements of Small Animals
- Merck Veterinary Manual: Diabetes Mellitus in Dogs and Cats
- AAFCO: Reading Labels
- FEDIAF: Carbohydrate Expert Review
- Agroscope: Demarcation between animal feed and veterinary medicinal products
- FEDIAF: Labelling Code
