Thursday, October 22, 2009
Eating the Rainbow
There was an interesting article this morning about the consumption patterns of Americans in terms of color that made me think of my theory of eating the rainbow everyday. It is my understanding that the color of fruits and vegetables is directly related to the antioxidants and phytonutrients the produce contains. This concept has been popular for a long time and instead of trying to remember what each color family provides I try to feed us food from each color everyday. I have summarized the food by color category below and included an abbreviated list of the health benefits of each color category, as I understand it.
The allium portion of the white food family (garlic, onion, and shallots) is high in allicin. Allicin is thought to reduce cholesterol and blood pressure. I always peel and smash or mince my garlic 10 minutes before I need to use it. A few years ago I read that in order for the allicin in garlic to develop the cloves need to be cut or smashed and they need to stand for 10 minutes to give the allicin time to develop. If you apply heat to the garlic sooner than 10 minutes you aren’t getting the full nutritional benefit of the garlic. The consumption of both garlic and onions is associated with a reduction in cancer so I use them liberally in my cooking. I have also found that by using more aromatics in general I am able to reduce our salt consumption. I will cover the problems with sodium in another post.
Yellow and Orange Food
These foods are rich in carotenoids both beta-carotene and alpha-carotene. Consuming a diet rich in carotenoids has been associated with a reduction in cardiovascular disease, cancer, and arthritis. It has been speculated that carotenoids boost the immune system to produce more natural killer (nk) cells and inhibit the growth of cancer. Citrus fruit contains d-limonene, which is associated with a reduction in skin cancer. Since the d-limonene is located in the skin of the citrus I use that liberally in my cooking. I buy organic citrus and scrub the skin well before zesting the fruit.
Foods in this category seem to have either lycopene or anthocyanins. Lycopene is the found in tomatoes, watermelon and pink grapefruit. Consuming lycopene is associated with a reduction in cancer particularly prostate cancer. The lycopene in tomatoes is most bioavailable if the tomatoes are cooked and they are consumed with fat. Additionally there is evidence that lycopene may reduce the risk of cardiovascular disease. If you watched “The Truth About Food”, there have been British studies that link the consumption of tomato paste with a reduction in skin cancer. Anthocyanins may protect cells from DNA damage thereby reducing the probability of cancer. There are animal studies that link the consumption of red berries with a slowing of the rate of growth of existing cancer. The skin of red apples is packed with antioxidants. I have read multiple studies with indicate the skin is anywhere from 5 to 12 times more nutritious than the apple flesh. Apples are typically a highly sprayed crop so I try to buy organic apples when I can find them. Otherwise I have a veggies scrubber that looks like a nylon pot scrubber that I used to thoroughly clean the apple under warm water. If you still feel anything on the apple skin you can add a little baking soda and scrub again. Be careful to rinse thoroughly so the apple isn’t gritty or salty.
Green leafy vegetables are rich in folate, which is associated with a reduction in birth defects. I read recently about a recent Chinese study that linked the consumption of green leafy vegetables with a lower risk of breast cancer. Cruciferous vegetables are also in this category and contain sulforaphane and indole 3. These compounds are thought to reduce most cancer cell lines by causing cancer cells to commit suicide and blocking blood vessel growth. Some scientists are recommending a daily serving of cruciferous vegetables to reduce overall cancer risk. It is important to remember that cruciferous vegetables need to be lightly cooked to maintain nutrition. Additionally I have read that combining broccoli and tomatoes together seems to have a synergistic effect and both are more powerful in animal studies when consuming together in a meal. This is why I will frequently add broccoli to my red sauce or have it as a side dish with my southern Italian meals.
Blue and Purple Food
The only color family of produce I used to have difficulty consuming was this one. I love eggplant but sometimes I get tired of it. I solved this problem at our house by having a purple smoothie most mornings. This category of produce is full on anthocyanins. We have all read about the health benefits of wild blueberries, which are credited to the anthocyanins. These phytonutrients are thought to have cardiovascular benefits, in addition to fighting cancer by inhibiting the growth of new blood vessels the cancer tumor needs to continue to grow.
If you ask me if I can recite all of this from memory the answer is no. Much of it is now stuck in my head, but not all of it. To make the process easy for myself I try to make certain we consume at least 2 servings of each color category every day. Putting the wild blueberries in our morning smoothies really made it much easier to get our purple food everyday which was our neglected category.
I hope everyone has a great day today. I will be back later with a recipe or two.