Beyond water, fruits and vegetables are generally low in protein and lipids but rich in carbohydrates. These carbohydrates occur mainly as natural sugars, starches, and dietary fiber, which provide energy and contribute to digestive health. Fiber, in particular, is a key reason fruits and vegetables play such an important role in preventing constipation, supporting gut microbiota, and helping regulate blood glucose levels.
Despite their modest protein and fat content, fruits and vegetables are valuable sources of essential micronutrients, including vitamins, minerals, and a range of bioactive compounds. Vitamin C, folate, potassium, and various antioxidants—such as carotenoids and flavonoids—are commonly abundant. These micronutrients support immune health, promote normal cell function, and help protect the body from oxidative stress.
Only a few fruits contain significant lipid levels, most notably avocado and olive, each of which may contain up to 15% fat. These exceptions are rich in monounsaturated fatty acids, which are associated with heart health and anti-inflammatory effects. In contrast, oilseeds such as peanuts, soybeans, and palm kernels—though botanically plant products—are not typically classified as fruits or vegetables due to their distinctly different nutritional roles and culinary uses.
In most fruits and vegetables, the small amount of lipid present occurs mainly within cell membranes. These membrane lipids are essential for maintaining the structural integrity of cells and their organelles, providing flexibility and acting as platforms for crucial metabolic processes. The fatty acids that make up these membrane lipids tend to be highly unsaturated, a feature that helps maintain fluidity and proper functioning within living tissues.
Chemical Composition and Nutritional Value of Fruits and Vegetables
