What is the difference between fruit and vegetable foods?
It sounds like a trick question. Celery is clearly not like an apple or orange. But what about avocados, cucumbers, tomatoes and pumpkins? Many would guess at least one of these is a vegetable. In truth, they are all fruits. In fact, so are grains and nuts, beans, sunflower seeds, corn kernels and pea pods.
But What About The Food Pyramid?
That’s right; the organization of the food pyramid is a bit misleading. With separate categories for grains and protein foods like beans and nuts, we think of these food groups as their own thing, and plan our meals accordingly. Botanists say this method is not precisely accurate, though. Fruits and vegetables are more fundamentally defined by their role in nature, long before they ever reach our dinner table.
We tend to think of fruits and vegetables from a culinary perspective, judging them based on how they taste in our mouth. By this logic, fruits are sweet and sometimes tart, while vegetables are often associated with savory or salty dishes. Plantains are starchier vegetables, while bananas are sweet fruits. But there is a deeper botanical logic at play, and the delicate sweetness of the berry and banana hints at it.
Fruits in Evolution
Many plants evolved to propagate in nature through their tasty fruits. Fruits are sweet or tart because they contain natural sugars (fructose) and organic acids. With these compounds, each fleshy, colorful snack is biologically designed to entice the right creatures to pick it and eat it, thereby spreading the seed along with the plant’s genetic information. That sweetness and seed-containing plant parts go together is no surprise; they are both key players in the reproductive cycle of an angiosperm.
The fruits and vegetables we eat correspond to the different parts of a plant. Fruit is the seed-associated part of a plant. It is a mature plant ovary. That’s why scientists consider grains, nuts and beans to be fruits; protecting and transporting the seed is their central function. Biologically speaking, grains are fruit-lined seeds; nuts are actually fruits, and beans are legumes—a special kind of fruit on plants in the Leguminosae family.
Vegetables are the product of evolution, too. A ‘vegetable’ is one of the vegetative organs of the plant body—the roots, stems or leaves. While fruits assist with reproduction, vegetative organs help plants live in the here and now. As health sentries, these organs perform vital functions like photosynthesis. If the plant is asexual, they take up the role of reproduction, too. Together, fruit and vegetables drive the life cycle of plants.
In practice, there’s not always a clear-cut difference between fruits and vegetables. Sometimes, it just depends on who you ask. If you ask U.S. Customs about rhubarbs, for instance, they will insist the ‘first fruit of the season’ is exactly that. Yet, the rhubarb is classed as a vegetable by botany and culinary types, since the mouthpuckering ‘fruit’ is actually part of a leaf on the original plant.