At WHFoods, we receive frequent questions about the advantages and disadvantages of raw versus cooked foods. This week we will begin a series of editorials addressing various aspects of this topic starting with the nutrient-richness of raw vs. cooked foods.
At WHFoods, we think about "raw" and "cooked" as being part of a continuum that begins with fresh, whole foods which have never been heated or processed in any way and continues on through several basic cooking methods. However, when it comes to cooking, the comparison between raw and cooked foods in terms of their taste and health benefits is better described as a comparison between raw and "optimally cooked," which for us means minimally cooked in a way that avoids as much nutrient loss as possible, while bringing out a food's vibrant colors, flavors and aromas.
Provided that they are fresh, raw foods have an overall greater nutrient richness than cooked foods, although optimal cooking techniques may increase the bioavailability of the nutrients in raw foods. We have never seen a published study that contradicts this basic relationship between raw and cooked foods. In addition, it's important to pay close attention to the circumstances being described in this comparison of raw versus cooked foods. The first circumstance is "fresh." It would be quite easy to find raw and deteriorating broccoli florets - long past time of harvest, and/or harvested too late in their life cycle - that were less nutrient-rich than frozen broccoli florets that had been blanched (very briefly boiled) prior to freezing. In addition, the blanched-and-frozen broccoli florets are likely to be more attractive than the raw and deteriorating ones. Fresh is an enormously important quality at WHFoods, and it is particularly important when considering the nutrient richness advantages of uncooked foods.
The words "overall greater" in the phrase "overall greater nutrient richness" is an equally important part of the raw-cooked relationship described above. It is not difficult for cooking to increase nutrient richness for a single nutrient, or even a select group of nutrients, in a food. In other words, you might easily find a cooked food that has more of one particular nutrient than the same food in raw form. A good example would be the amount of lycopene present in tomato. If you eat 32 calories' worth of raw, fresh tomato, you can get an outstanding amount of the carotenoid lycopene: 4,631 micrograms. In fact, this low calorie level and high lycopene content correspond to the one-cup amount of raw tomato that we use as our website serving size. But if you eat 32 calories' worth of cooked tomato, you can get an even greater amount of lycopene: 5,474 micrograms. So, in the particular case of tomatoes and their lycopene content, the raw versus cooked comparison tilts in favor of cooked tomatoes. However, if you consider not just lycopene but the hundreds of nutrients provided to us by tomatoes, their overall nutrient richness still tilts back in favor of raw. However, to see why this does not to imply that there is an absolute advantage for raw over cooked see our Newsletter next week..