Cooking doesn’t reduce nutritional quality of tomatoes

tomatoes keep their nutrition when cooked

I have some other patients that have asked about the benefits of a raw food diet, and while there are many benefits, there are a few drawbacks to a completely raw food diet.

The reality is that some foods actually have higher nutritional value if they are cooked versus eaten raw. Tomatoes are a prime example of this feature. Cooked tomatoes actually have higher levels of antioxidants such as lycopene when compared to raw tomatoes.

One reason that raw food diet advocates give for their eating habits is that cooking most foods decreases the amount of vitamin C in the food. However, it’s important to look at the entire anti-oxidant properties and profiles of the vegetable or fruit and not just the Vitamin C levels. This focus on a solitary vitamin or nutrient may be why many studies that look at supplementation do not show significant impact on a variety diseases, but diets high in foods that contain those nutrients do demonstrate a positive effect.

One study that clearly demonstrates this is a 2002 study in the Journal of Agriculture Food Chemistry by researchers from Cornell University. The researchers compared to vitamin C,  lycopene, and total antioxidant activity between raw tomatoes and tomatoes that were cooked for various times ranging from 2 minutes to 30 minutes. Lycopene is a carotenoid that acts as a powerful antioxidant and also is the reason for the red coloring of tomatoes. The results are summarized below but basically demonstrate just a slight decrease in vitamin C concentration between the raw tomato and  cooked tomatoes, while there was a significant increase in the lycopene and total antioxidant concentrations.

Nutritional Qualities Of Raw Versus Cooked Tomatoes

Cooking timeVitamin C concentrationLycopene concentrationAntioxidant concentration
2 minutes0.683.115.29
15 minutes0.645.455.53
30 minutes0.545.326.70

Vitamin C, lycopene and total antioxidant concentrations of raw and cooked tomatoes

My take on this study is that there is no one correct type of diet or method of eating. While there are benefits of raw food, there also are measurable benefits for some foods that are cooked. Please pass spaghetti sauce.