If you’re trying to eat more vegetables for their nutrients, how you cook them may matter more than you think.
A new study published in Food Chemistry found that different cooking methods can dramatically change how much of certain nutrients your body can access from vegetables like carrots and tomatoes. In some cases, cooking increased the availability of carotenoids, compounds linked to vitamin A and other health benefits, compared to eating the vegetables raw.
Researchers looked at several common cooking methods, including oven baking, microwaving and air frying. They then measured how much of these nutrients became available during digestion.
For carrots, cooking made a striking difference. Baking them in the oven led to about a ninefold increase in total carotenoid availability compared to raw carrots. Tomatoes showed a smaller but still meaningful boost. Cooking them in an oven or air fryer increased carotenoid availability by about 1.5 times.
The findings help explain something nutrition researchers have long observed. Cooking can break down plant cell walls, making it easier for the body to access certain nutrients that might otherwise pass through partially undigested.
The study also found that some cooking methods delivered similar nutrition benefits while using far less energy. For carrots, microwaving provided strong nutrient availability with about 96% less electricity use than a conventional oven. For tomatoes, air frying offered a balance of improved nutrient availability and about 80% lower energy use.
Carotenoids include compounds like alpha-carotene and beta-carotene, which the body can convert into vitamin A. These nutrients play a role in vision, immune function and skin health. Tomatoes and carrots also contain other carotenoids that may help protect the skin from ultraviolet damage.
Still, the results do not mean one cooking method is universally “best,” or that raw vegetables are inferior. The study measured how much of these compounds became available during digestion in a controlled setting; not how much people actually absorb and use in real life.
This research was supported by the European Union and the Junta de Andalucía through the European Regional Development Fund.