Answer : Overall, the nutritional differences between types of tomatoes-including grape, cherry and other bite-sized varieties, as well as plum, Roma and other larger options-are quite small, probably less than the variations by season and producer within any one type. We checked with two leading producers of grape tomatoes and got slightly different nutritional data. In general, though, grape tomatoes are similar to regular tomatoes in calories, carbohydrates, dietary fiber and sugar content. Both grape and regular tomatoes supply about 25% of your daily vitamin A and 32% of daily vitamin C. A cup of either grape or regular tomatoes has a glycemic load (see story on page 1) of about 2, so neither choice will significantly raise blood sugar. It may be that the grape tomatoes youre enjoying have a higher sugar content and sweeter taste than the currently available regular tomatoes-but not necessarily different from regular tomatoes found later in the season.
One difference noted in 2002 research in the Journal of Agricultural and Food Chemistry is that cherry tomatoes have higher levels of antioxidants than normal-sized tomatoes; this would likely also be true for the similar grape tomatoes. The research also reported that riper cherry tomatoes have higher levels of carotenoids and antioxidants than those picked when less ripe.