Because grapefruit contains carbohydrate, consuming the citrus fruit will cause your blood sugar levels to rise. But grapefruit has a low glycemic index score, meaning that it will not raise your blood sugar levels as much as foods with a medium or high glycemic index score.
Nutrition
Carbohydrate, unlike protein and fat, affect your blood glucose levels. Sugar, starch, and fiber make up the three main categories of carbohydrate. Grapefruit contains natural sugars and fiber, but no starch. Keep in mind that sugar and starch raise your blood glucose, but fiber does not. One half of a medium size raw grapefruit contains 8.93 g of sugar carbohydrate and 1.4 g of fiber carbohydrate. This means that half of a grapefruit contains 10.33 g of total carbohydrate.
Total Carbohydrate
When counting carbohydrates in order to monitor your blood sugar levels, keep track of your total carbohydrate intake, not just your sugar intake. Grapefruit provides a relatively low amount of total carbohydrate, containing 10.33 g. By comparison, a medium apple with skin contains 23.4 g of total carbohydrate, a medium banana contains 23.88 g of total carbohydrate, and a medium pear with skin contains 22.94 g of total carbohydrate. The 10.33 g of total carbohydrate in half of a grapefruit is especially low considering that any food that contains less than 5 g of total carbohydrate will not have a significant effect on your blood sugar.
Soluble Fiber
Grapefruit, like most varieties of fruit, provides a good source of dietary fiber. The soluble fiber in grapefruits may help stabilize your blood sugar levels. Soluble fiber forms a gel substance in your stomach, which slows down your digestion. Soluble fiber helps carbohydrates get absorbed into your bloodstream at a slower and steadier pace than carbohydrates with little or no soluble fiber. When you consume grapefruit and other forms of soluble fiber, your blood sugar levels will more likely remain fairly stable and within a healthy range.
Healthy Diet
Based on a 2,000-calorie diet, most men and women should consume about 225 g to 325 g of total carbohydrate per day. Fruit, an important source of vitamins, minerals and dietary fiber, provides an important source of carbohydrate. The United States Department of Agriculture recommends that adults consume about 1 1/2 cups to 2 cups of fruit daily. Eating grapefruit can help fulfill your daily fruit requirement. One medium grapefruit counts as 1 cup of fruit.
References
- American Diabetes Association: Food and Fitness -- Carbohydrates
- American Diabetes Association: Food and Fitness -- Glycemic Index and Diabetes
- American Diabetes Association: Food and Fitness -- Diabetes Superfoods
- MayoClinic.com: Nutrition and Healthy Eating -- Glycemic Index Diet: Losing Weight with Blood Sugar Control, Nov. 24, 2009
- United States Department of Agriculture Nutrient Database
- American Diabetes Association: Food and Fitness -- Carbohydrate Counting
