Eat fruit, but know how it affects blood sugar

Fruit Harvest Selection in BowlsI know I should be eating more fresh fruit, but I have type 2 diabetes. Last weekend I enjoyed a few slices of watermelon, and I was surprised when I tested my blood sugar and saw that it spiked over 200. Should I forget about eating more fresh fruit?

No! Fresh fruit should be included in every diet, even if you have diabetes. Aim for 1.5-2 cups a day.

Fresh fruit contains all sorts of nutrients, including vitamins, minerals, phytochemicals and fiber. As you probably experienced with the watermelon, fruit can also satisfy your sweet tooth while providing huge nutritional benefits that cake and candy simply don’t offer.

But you should be aware that, as with any carbohydrate-containing foods, portion size matters to your blood sugar. And, different fruits have different levels of carbohydrates and fiber, both of which affect your blood sugar, or blood glucose. You likely already know that unmanaged high blood glucose can cause serious, even life-threatening consequences, including blindness, kidney disease, heart and vascular disease, and neuropathy (a disease of the nervous system).

The American Diabetes Association recommends that people with diabetes keep their blood glucose level to less than 180 milligrams per deciliter of blood two hours after eating. For people without diabetes, the normal level is less than 140 mg/dl. You and your doctor may have set your after-meals target lower, but whatever the case, it’s good to recognize what might spike your blood sugar so you can take steps to reduce your risk.

Fruits lower in carbohydrate and higher in fiber will likely have less of an effect on your blood sugar. Below is the calorie, carbohydrate and fiber content for specific portion sizes of some common fruits. Find information about other fruits in the National Nutrition Database, available under “What’s In Food”

  • Raspberries, 1 cup (4.3 ounces): 65 calories, 15 grams carbohydrate, 8 grams fiber.
  • Peach, medium (5.3 ounces, about 1 cup sliced): 60 calories, 14 grams carbohydrate, 2 grams fiber.
  • Strawberries, 1 cup halves (5.4 ounces): 50 calories, 12 grams carbohydrate, 3 grams fiber.
  • Orange, 1 cup sections (6.5 ounces): 85 calories, 21 grams carbohydrate, 4.5 grams fiber.
  • Blueberries, 1 cup (5.2 ounces): 85 calories, 21 grams carbohydrate, 3.5 grams fiber.
  • Apple, extra small (3.5 ounces, about 1 cup sliced): 55 calories, 21 grams carbohydrate, 3.5 grams fiber.
  • Cantaloupe, 1 cup diced (5.5 ounces): 55 calories, 13 grams carbohydrate, 1.5 grams fiber.
  • Banana, extra large (5.4 ounces, about 1 cup sliced): 135 calories, 35 grams carbohydrate, 4 grams fiber.
  • Honeydew, 1 cup diced (6 ounces): 60 calories, 15 grams carbohydrate, 1.5 grams fiber.
  • Grapes, 1 cup (5.3 ounces): 105 calories, 27 grams carbohydrate, 1.5 grams fiber.
  • Watermelon, 1 cup diced (5.4 ounces): 45 calories, 11.5 grams carbohydrate, 0.5 grams fiber.

Chow Line is a service of the College of Food, Agricultural, and Environmental Sciences and its outreach and research arms, Ohio State University Extension and the Ohio Agricultural Research and Development Center. Send questions to Chow Line, c/o Martha Filipic, 2021 Coffey Road, Columbus, OH 43210-1043,

Editor: This column was reviewed by Dan Remley, specialist in Food, Nutrition and Wellness with Ohio State University Extension. OSU Extension is the outreach arm of the College of Food, Agricultural, and Environmental Sciences at The Ohio State University.

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Watermelon tasty, nutritious

160145128My favorite fruit is watermelon. Since it’s so watery, does it offer much nutrition?

You’re correct that watermelon is “watery.” In fact, it’s more than 90 percent water. Still, two cups of diced watermelon (about 10 ounces) offers 38 percent of the vitamin C you need in a day, 32 percent of vitamin A, as well as a small amount of protein and fiber, and all for a mere 85 calories.

Watermelon is also a good source of lycopene, a phytonutrient that gives your favorite fruit (as well as tomatoes and pink grapefruit) its red color. Lycopene protects against prostate cancer and possibly other cancers, and also protects cells from damage associated with heart disease.

In addition, citrulline in watermelon is converted into arginine, an amino acid that plays a key role in cell division, wound healing, and the removal of ammonia in the body.

Watermelon also offers some potassium, which is helpful because most Americans don’t get enough of it. Potassium helps control blood pressure and possibly prevent strokes.

Part of the challenge with watermelon is choosing one that’s ripe. That’s not always easy to figure out, according to “Selecting, Storing and Serving Ohio Melons” ( from Ohio State University Extension. Here are some suggestions from the fact sheet:

  • Examine the rind and find the spot where the melon had been resting on the ground — it should be yellow-white. If it’s white or pale green, it was picked too early.
  • Scratch the surface of the rind with your thumbnail. If the outer layer slips back with little resistance showing the green-white under the rind, the watermelon is ripe. If all you get is a darker depressed line, the melon isn’t ripe.
  • When purchasing cut watermelon, look for more red flesh and less white rind to find riper melons. White seeds usually indicate the melon was picked too early — unless you’re looking at a seedless watermelon. In that case, any white seeds you see are really just empty seed coats.

If you think your watermelon isn’t quite ripe yet, keep it at room temperature for a few days. It will continue to ripen if it’s not too mature. But only whole, uncut watermelon should be left unrefrigerated. Once it’s cut, watermelon needs to be kept at 40 degrees F or below.

Before cutting into watermelon (or any melon), be sure to thoroughly rinse it under clean running water. You may even want to scrub it with a soft-bristled brush while rinsing. This will help remove any contaminants on the rind that could spread to the fruit inside when you slice through it.