The difference between fruit and vegetables can sometimes be clear. A peach is always considered a fruit, and a carrot is definitely a vegetable. But in the Venn diagram relating these two produce categories, there's a sizable region of overlap. It results from the fact that "fruit" and "vegetable" are defined differently depending on whether you're a gardener or a chef, according to the European Food Information Council (EUFIC).

Dead center of the overlapping region sits the tomato. This can sometimes be categorized as a fruit, and sometimes a vegetable.

Botanically speaking, what is the difference between fruit and vegetables? According to the book Postharvest Physiology and Biochemistry of Fruits and Vegetables, fruits are seed-bearing structures that develop from the ovary of a flowering plant. 

Related articles

—What if you ate only one type of food?

—Why is mold fuzzy?

—Why are bananas berries but strawberries aren't?

Vegetables, on the other hand, are all other plant parts, such as roots, leaves and stems. By those standards, seedy outgrowths such as apples, squash and, yes, tomatoes are all fruits, while roots such as beets, potatoes and turnips, leaves such as spinach, kale and lettuce, and stems such as celery and broccoli are all vegetables. 

The outlook is quite different in culinary terms, however. A lot of foods that are (botanically speaking) fruits, but which are used in savory dishes rather than sweet ones, are typically considered vegetables by chefs. This includes such botanical fruits as eggplants, bell peppers and tomatoes, according to EUFIC.

Spinach and other plant leaves are classed as vegetables. (Image credit: Getty Images)

Another factor that can impact someone’s perception of what is a fruit or vegetable is language and culture, according to a 2011 survey, published in the journal Public Health Nutrition. Rice was considered to be a vegetable by 20% of respondents, who were all adults in the US. When compared with English speakers, Spanish speakers were more likely to call rice a vegetable while Chinese speakers were less likely. Beans, which are often grouped in the vegetable category, also divided opinions. Compared to Spanish speakers, English speakers were more likely to label them as vegetables.

Debate over the difference between fruit and vegetables can sometimes reach such a fever pitch that the law must step in. In the 1893 United States Supreme Court case Nix. v. Hedden, the court ruled unanimously that an imported tomato should be taxed as a vegetable, rather than as a (less taxed) fruit, according to the Mercer Law Review. The court acknowledged that a tomato is a botanical fruit, but went with what they called the "ordinary" definitions of fruit and vegetable — the ones used in the kitchen. 

Additional resources

To find out more about fruits and what defines them, you can read this article by The New York Botanical Garden. For research about the nutritional benefits of fruit and vegetables, head to Harvard’s School of Public Health page. 

Bibliography

"The Role of the Dictionary in Legal Thought". Mercer Law Review Vol. 039 Issue 03-046. https://ursa.mercer.edu/bitstream/handle/10898/7559/49_39MercerLRev961(1987-1988).pdf?sequence=1

"Postharvest physiology and biochemistry of fruits and vegetables". Yahia, E. M., & Carrillo-Lopez, A. (2018). https://books.google.co.uk/books?hl=en&lr=&id=lMlaDwAAQBAJ&oi=fnd&pg=PP1&dq=botanical+definition+fruit+and+vegetables

"The meaning of 'fruits' and 'vegetables'". Public Health Nutrition (2011). https://pubmed.ncbi.nlm.nih.gov/21272414/