Diabetes Forecast

Serving Size Matters

By Madelyn L. Wheeler, MS, RD, CDE, FADA, CD, Associate Editor , ,

Small, medium, and large: We often describe foods this way, but these words are vague, and one person's "large" can be another's "small." For some, this may not matter too much, but people with diabetes who are counting carbohydrates and trying to fine-tune their blood glucose control need these words to be precise.

For example, bananas contain about 15 grams of carbs per 2 1/2 ounces of fruit. This is equal to about 4 ounces of unpeeled banana—pretty "small" when you consider the size of most bananas on display in your market's produce aisle. Or, if you're cooking from a recipe, you'll often find an ingredient like "one medium potato, peeled." What's "medium"? Unless a weight is provided—"one medium potato (about 6 oz.), peeled"—you might use a larger potato, perhaps even doubling the carb content. Plus, you'll end up with a dish that doesn't taste quite as it should.

Fast-food chains are notorious for their notions of what small, medium, and large servings are, especially for fries and sodas. And a small size at one chain may be a medium at another.

So, what to do if you're trying to keep a sharp eye on carbs?

  • Look for recipes and cookbooks that specify weights for fresh fruits and starchy vegetables (such as potatoes, ears of corn, and winter squash).
  • Plan your fast-food excursions by going first to the website of the chain you're going to patronize and checking nutrition facts. The sites usually give a weight for each food size.
  • Most important, find or make a list of your favorite whole fresh foods that equates size with weight and carb content (preferably 15 grams), and use the scales in the produce section of your market.

The booklet Choose Your Foods: Exchange Lists for Diabetes lists fruits in portions equivalent to 15 grams of carbohydrate along with the portion's weight (including skin, core, seeds, and rind)—the way you find them in the market. The booklet is available at shopdiabetes.org.

The Food and Drug Administration gives food stores nutrition facts for the 20 fruits and 20 vegetables most commonly eaten in the United States. (Note: The weight given in this list is for the raw edible portion of each, and the information is only for a medium size, not small or large.) If you don't see the list posted, ask your store's produce manager to provide it.

The American Diabetes Association's MyFoodAdvisor, enables you to search online for foods' nutrient content. Another good resource is the federal Agricultural Research Service's online database.

Sizing up what you're about to eat may require a little homework, but it will help you make the grade on good blood glucose control.



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