At Rejuice we get asked this question a lot and so this week we looked at credible sites and scientific studies comparing the two. And what we found was ..
There is no hard evidence to support either view.
Some of the research found that the people who ate raw vegetables were healthier overall, while others cited better results with cooked vegetables.
What was clear was that those who ate the most fruits and vegetables (cooked or raw) overall had lower rates of disease - especially cancer.
The take-away for us was to understand that some foods contain more nutrients cooked, and some had more nutrients raw.
Cooking: softens the plant matrix (tough cell structure of plants), which helps to release more phytochemical compounds. Thus, depending on the vegetable being cooked, the cooking method, and the phytonutrient compound being studied, conservative cooking (steaming, making soup) can provide greater nutrient availability. We also increase the plant proteins in the diet, especially important for those eating a plant-based diet with limited or no animal products.
Veggies you should definitely turn the heat on for include carrots and asparagus because cooking makes it easier for our bodies to benefit from some of their protective antioxidants, specifically ferulic acid from asparagus, and beta-carotene, which we convert to vitamin A, from carrots.
A study published in The British Journal of Nutrition last year found that a group of 198 subjects who followed a strict raw food diet had normal levels of vitamin A and relatively high levels of beta-carotene (an antioxidant found in dark green and yellow fruits and vegetables), but low levels of the antioxidant lycopene.
So roast your tomatoes slowly or make a cooked sauce because it helps to break down the plant cell walls, allowing us to better absorb the antioxidant lycopene -
shown to have antioxidant properties and to reduce the risk of cardiovascular disease and cancer.
The rest is a bit confusing. For example, while some studies cited that some veggies, like broccoli were healthier raw than cooked, others noted that
heat damages the enzyme myrosinase, which breaks down glucosinates (compounds derived from glucose and an amino acid) in broccoli into a compound known as sulforaphane. On the other hand, indole, an organic compound, is formed when certain plants, particularly cruciferous vegetables such as broccoli, cauliflower and cabbage, are cooked. According to research in The Journal of Nutrition in 2001, indole helps kill precancerous cells before they turn malignant.
Another reason to turn up the heat sometimes:
Humans are the only primates that cook their food. Raw foods have a low caloric yield, which imposes “a tradeoff between body size and number of brain neurons, which explains the small brain size of great apes compared with their large body size.” Cooking our foods allowed us to spend less time feeding. Cooked food provided a greater amount of brain neurons and drove humans to evolve with an increased brain size and functioning capability. Essentially, this might mean that humans would not have evolved were it not for cooked foods.
As always, the important thing is BALANCE!
Balancing raw foods with cooked foods is your best strategy for overall health and wellbeing!