It would be easy to assume that red seedless grapes are a high-fiber food. After all, they’ve got plenty of crisp skin, and it’s no secret that that edible fruit skins are a great source of dietary fiber. Your mom always told you that an apple’s skin was its best part, right? Like their sweet, juicy flesh, however, grape skins are highly digestible -- meaning the fruit is relatively low in fiber.
For about 100 calories, 1 cup of red or green seedless grapes supplies 1.4 grams of fiber, or fewer than 6 percent of the daily value for dietary fiber. It takes about 35 grapes to make a 1-cup serving, which means that for every 10 red seedless grapes you eat, you get about half a gram of fiber. According to the U.S. Department of Agriculture, about 60 percent of the fiber in a seedless grape is insoluble, the kind that promotes efficient digestion and helps prevent constipation. Soluble fiber -- the kind that supports normal cholesterol and blood sugar levels -- accounts for about 40 percent of a grape’s fiber content.
Adequate intake guidelines for fiber recommend getting at least 14 grams for every 1,000 calories you consume. Based on the average daily calories of most women under the age of 51, this amounts to about 25 grams of fiber a day. Coincidentally, the U.S. Food and Drug Administration sets the daily value for dietary fiber at 25 grams. The daily value is used to determine if a food is a significant source of fiber. Foods that have at least 2.5 grams of fiber per serving, or 10 percent of the daily value, are considered good sources, while those that contain at least 5 grams per serving, or 20 percent of the daily value, qualify as high in fiber. With less than 2.5 grams per serving, seedless grapes don’t count as a good source of fiber.
If you’re looking to boost your fiber intake with grapes, eat muscadines, a relatively thick-skinned kind of grape that ranges in color from bright green to deep purple or black. Ounce for ounce, muscadine grapes are about 75 percent higher in fiber than seedless grapes. For a bit more than 100 calories, a serving of 35 muscadines delivers 7 grams of fiber, or 28 percent of the daily value. You’d have to eat about 520 calories worth of red seedless grapes to get the same amount of fiber. Gooseberries, a slightly larger grape-like berry, are also significantly higher in fiber than seedless grapes -- a 1-cup serving provides about 65 calories and 6.4 grams of fiber, or about 26 percent of the daily value.
Seedless grapes are a low-fat source of several vitamins and minerals, but they only contain moderate amounts of most nutrients. One cup of red or green seedless grapes delivers 28 percent of the daily value for vitamin K, 8 percent each of the daily values for vitamin C and potassium and 7 percent each of the daily values for vitamin B-6 and thiamine. Red grapes, in particular, are an excellent source of flavonoids, powerful antioxidants that protect against heart disease by preventing blood clots and vascular damage. Grapes are a refreshing warm-weather snack and a naturally sweet dessert option. Halved grapes bring flavor and texture to almost any kind of salad, ranging from the fresh green variety to warm grain-based salads as well as pasta, chicken and tuna salads.
- USDA Nutrient Data Laboratory: Grapes, Red or Green (European Type, Such As Thompson Seedless), Raw
- USDA National Agriculture Library: Individual Sugars, Soluble, and Insoluble Dietary Fiber Contents of 70 High Consumption Foods
- Colorado State University Extension: Dietary Fiber
- USDA Center for Nutrition Policy and Promotion: Dietary Guidelines for Americans, 2010: Foods and Nutrients to Increase
- USDA Nutrient Data Laboratory: Grapes, Muscadine, Raw
- USDA Nutrient Data Laboratory: Gooseberries, Raw
- Wellness Foods A to Z; Sheldon Margen, M.D., et al.
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