Considering that many foods come in different shapes and sizes, knowing the amount of carbohydrate by weight is another helpful tool. Fruit, for example, can be small or very large, peeled and pitted. Or slices of bread can be deceptive depending on the size of the loaf and how thick you may cut the slice. Calculate the amount of carbohydrate by food weight for items you are unsure about.
In this section, you will learn about:
- How do I calculate carbohydrate content from food weight?
- Food Weights
- Carbohydrate FACTOR-the carbohydrate content of food based on weight
Should I weigh my foods?
Weighing food may seem like a lot of work. Weighing food isn’t for everyone. Your registered dietitian can help guide you. So who benefits the most from taking this extra step?Here’s the best advice about weighing foods:
If you have Type 2 Diabetes and are managing your diabetes with diet and exercise alone, or with oral pills, you may not need to take the extra step of weighing foods to count your carbohydrates. Why? Weighing foods will not make a big difference in dosing your diabetes medicines day to day. Reading food labels and using carbohydrate exchanges will be your most helpful carbohydrate-counting tools. However, you may wish to experiment with weighing certain foods when you are unsure of the carbohydrate count. For people with Type 1 and Type 2 Diabetes who are treated with insulin, getting the most accurate carbohydrate count may help you better control your blood sugars.
Every gram of carbohydrate may mean a change in your insulin dose. So if you are managing your diabetes with insulin before meals, try weighing certain foods when you are unsure of the carbohydrate count. Remember, weighing certain food items doesn’t mean you will have to weigh every food for the rest of your life! But taking some time in the beginning to weigh the foods you are unsure about may help you feel more confident with your carbohydrate counting in the long run.
Calculate carbohydrates by how much the food weighs if you are unsure.
How do I calculate the carbohydrate content from the food weight?
You need :Food weights
Food weights are measured in either ounces or grams. Don’t confuse grams of food weight with grams of carbohydrate. The food weight simply is the weight of the actual food item when placed on the food scale.Don’t confuse grams of food weight with grams of carbohydrate.
You can find information about Food Weight from a variety of resources:
- The Food Lists for Meal Planning includes Food Weight for many items listed.
- List of food by weight.
- Nutrition Facts food labels on packaged foods may list a Food Weight along with the measured Serving Size.
- Carbohydrate counting and food composition books and online databases are available.
- Calorie King website or app
Food FACTOR
To calculate carbohydrate by food weight, you have to know how many grams of carbohydrate are in a given weight of the food. – this is referred to as the FACTOR. The food FACTOR can be expressed in either ounces or grams of a food item. Depending on your source of nutrition information, the grams of carbohydrate per food weight may be displayed differently. Sometimes, it will list the grams of carbohydrate per one ounce or gram. Or, it may list the grams of carbohydrate for multiple ounces or grams.The FACTOR equals the grams of carbohydrate per one ounce or one gram of a food item.
How do I count carbohydrates based on the food weight?
To calculate your carbohydrate count by food weight, use this basic equation:Your Food Weight X Carbohydrate FACTOR= Grams of Carbohydrate in that food
See our convenient tables that give you the grams of carbohydrate per food weight for common carbohydrate containing foods, including whole fruits and sliced fruits. If you are weighing the food in ounces, use the “Factor for Ounces.” If you are weighing the food in grams, use the “Factor for Grams”. Different FACTORS are available for whole (unpeeled with seeds/pits) fruit and sliced fruit (no seeds, pits, or rind). Be sure to use the right fruit Factor!Let’s walk through some examples:
Example 1: To calculate the grams of carbohydrate for a slice of bread:- Weigh your bread (in ounces) using a food scale – the weight is 2 ounces.
- Look up the FACTOR for bread (in ounces). The bread FACTOR is 15 grams of carbohydrate per one ounce.
- Multiply the weight of your slice of bread times the FACTOR.
- 2 ounces of Bread x 15 grams of carbohydrate per ounce equals 30 grams of carbohydrate.
- So that means your bread slice is 30 grams of carbohydrate.
- Weigh your whole apple (in ounces) using a food scale. For your apple, the weight includes the skin, core, seeds and stem. Let’s say your apple weighs 9 ounces.
- Look up the FACTOR for a whole apple. The whole apple FACTOR is 3.75 grams of carbohydrate per one ounce.
- Multiply the weight of your apple times the FACTOR for whole apples. 9 ounces of whole apple x 3.75 grams of carbohydrate per ounce equals 34 grams of carbohydrate.
- So that means your whole apple is 34 grams of carbohydrate.
- Weigh your whole apple (in grams) using a food scale. For your apple, the weight includes the skin, core, seeds and stem. Let’s say your apple weighs 252 grams.
- Look up the FACTOR for a whole apple. The whole apple FACTOR is 0.13 grams of carbohydrate per one gram.
- Multiply the weight of your apple times the FACTOR for whole apples. 252 grams of whole apple x 0.13 grams of carbohydrate per gram equals 33 grams of carbohydrate.
- So that means your whole apple is 33 grams of carbohydrate.
- Weigh your sliced apples (with skin) in ounces using a food scale. Let’s say your sliced apples weigh 6 ounces.
- Look up the FACTOR for a sliced apples (with skin). The FACTOR is 3.91 grams of carbohydrate per one ounce.
- Multiply the weight of your sliced apples times the FACTOR for sliced apples. 6 ounces of sliced apples x 3.91 grams of carbohydrate per ounce equals 23 grams of carbohydrate.
- So that means your bowl of sliced apples is 23 grams of carbohydrate.
You can weigh your food using either a scale that reads in grams or reads in ounces - 1 ounce is the same as about 28 grams.