When I give presentations on nutrition, I am frequently asked, "Which is healthier: raw or cooked vegetables?" This sounds like a simple question, but the answer is more nuanced. The short answer is that consuming both is important. While some vitamins are lost during cooking, others become more easily absorbed or more "bioavailable" during the cooking process.
In Praise of Raw Veggies
Generally, water-soluble nutrients like vitamin C and B vitamins are best consumed raw. These vitamins are found in sweet peppers (red, green, etc.), leafy greens (spinach, kale), and cruciferous vegetables, (broccoli, Brussels sprouts.) These nutrients are prone to degradation when exposed to heat, especially from boiling. Because these are water-soluble nutrients, the nutrients leech out in boiling water, and even through steaming.
Yikes! Raw Broccoli?
Does that mean you have to eat your broccoli raw? Not at all! Just choose a different cooking method besides boiling (and even steaming). Lightly sautéing, roasting, microwaving, and air-frying are all better options for preserving the vitamins in broccoli and similar foods, provided you don't overcook them.
In Praise of Cooked Veggies
Some nutrients, like beta-carotene in carrots or lycopene in tomatoes, are more bioavailable when the vegetables are cooked. That means you can better absorb the nutrients. Cooking breaks down the cell walls of vegetables, making certain nutrients more accessible and easier to digest. This can be especially important for people with digestive issues.
Of course, if you like raw carrots and tomatoes, keep enjoying them! Just consider roasting carrots or enjoying a tomato sauce once in a while. A tomato sauce prepared with a bit of fat, like olive oil, actually enhances the absorption of fat-soluble vitamins (such as vitamin A) and antioxidants.
