You’ve heard it all before and it’s something that most of us can’t argue with: eat fruits and vegetables. Of course, it’s the soundest nutritional advice out there and doesn’t require a fancy dietary approach or book to follow. I don’t think anyone could argue with the recommendation to eat plants several times a day. Solid science exists to show that eating fruits and vegetables helps to ward off chronic diseases like heart disease, cancer and diabetes.
There is some emerging research surfacing about fruits and vegetables to make your plant-based meals even smarter and more impactful. Here’s what you need to know:
1. Choose complexity: Most people get completely carried away with one fruit or vegetable. They get lodged in a food rut and start eating a food consistently. While a single food might have health merits, it is much better to get a wider sampling of plant-based foods in the diet. The complexity of different phytonutrients from several plant foods working together is going to be better than overdosing on any one fruit or vegetable. A study that might further convince you was one published in the Journal of Nutrition in 2006 (1). These researchers at Colorado State University showed that women who ate fruits and vegetables from 18 different botanical families (“high botanical diversity”) compared with just five botanical families (“low botanical diversity”) had reduced damage to their DNA after just two weeks. The two groups were eating about eight-nine servings of fruits and vegetables each day, so it wasn’t about the amount, but the diversity of what they were eating. Takeaway: It’s important to think in terms of getting the rainbow variety of different colors everyday in your meals. Get out of food ruts and start moving along the spectrum of health.
2. Cook vegetables, but not too much: One of the most popular questions I get is whether to eat vegetables raw or cooked. For most of you, the knee-jerk reaction would be to say that raw is the superior preparation method of the two. Raw food might be good for some nutrients like vitamin C, however, many people find it surprising that a majority of plant-based antioxidants and nutrients require some gentle cooking to make them active and accessible by the body. I am not talking lots of high-heat cooking, but subtle steaming (about one-two minutes) to the point that the vegetable turns a beautiful, vivid color, inviting you to eat it. In fact, a group of nutrition researchers (2) found that steaming led to a greater percentage of antioxidant activity in foods like green pepper (467% greater antioxidants compared with non-processed form), cabbage (antioxidant increase of 448%), carrots (antioxidant increase of 291%) and asparagus (antioxidant increase of 205%), just to name a few. Takeaway: A little heat with your veggies brings out their best protection for you.
3. Make good partnerships: There is something to be said about the synergy of putting certain foods together. Yes, they may taste more flavorful that way. However, there are also synergies that are more medicinal. For example, one helpful idea for barbequing season or any time you are grilling meats, is to include spices like turmeric and rosemary in the hamburger patty or on top of the meat. Those spices are very protective against the formation of reactive, cancer-causing chemicals (3). Another foodie tip? You will want to put a slice of lemon into your green tea to preserve the antioxidant-rich catechins. And, finally, here’s one of my favorites: the anti-inflammatory spice, turmeric, together with black pepper and oil is the best cooking trio and amps up the action of the king of spices, turmeric. Takeaway: Get to know the food combinations that are synergistic for truly “smart” eating.
4. Expect the unexpected: We get into what I call “food stereotypes,” where certain foods become known for various qualities. One great example is the banana. When I mention banana, you might think of potassium. However, an avocado has more than double the potassium of a banana (975 milligrams in a whole avocado vs. 422 milligrams in a banana). An added bonus of that avocado is that it also has more fiber than you think: 14 grams, which is more fiber than some people get in an average day. Another food stereotype is the tomato; it has become known for its lycopene content (a phytonutrient important for heart, prostate and immune health); however, research published in the British Journal of Nutrition in 2013 showed that lycopene was approximately 2.6 times more bioavailable from papayas than from tomatoes (4). Here’s another one: kale, the darling of the health field, has become somewhat famous for its high levels of lutein (a phytonutrient that helps with vision). Indeed, kale is fairly decent in lutein, but parsley is at the same level and even a tad higher, as shown by some more recent nutrition research (5). Somehow, parsley seems to get “lost in the dust” and kale gets all the attention when it comes to lutein. Takeaway: Don’t take “food stereotypes” at face value. There might be better food superstars to be exploring in your everyday eating.
5. See the larger potential of plants: We used to think of plant-based nutrients as being antioxidants. We still do, however, we now know more about phytonutrients playing not just a protective role against oxidative stress, but that they are integral in working to trigger activities within the cell like gene expression. In other words, what we eat changes the destiny of our DNA. Additionally, a newer learning is that phytonutrients have structural roles in the body, too. For example, lutein collects in the eye, in the macula; proanthocyanidins from blueberries localize to certain parts of the brain responsible for learning and memory; even beta-carotene/retinol is pivotal in ovaries and the process of ovulation. Takeaway: The plant foods we eat “become” us by affecting DNA expression and how organs function.
Yes, we all know we need to eat our vegetables, and what’s even more exciting is all the recent research that makes it even more enticing to do so. Take these five tidbits into your next plant-based meal to start eating smarter and in the full-spectrum way.
1 Thompson HJ, Heimendinger J, Diker A, O’Neill C, Haegele A, Meinecke B, Wolfe P, Sedlacek S, Zhu Z, Jiang W. Dietary botanical diversity affects the reduction of oxidative biomarkers in women due to high vegetable and fruit intake. J Nutr. 2006 Aug;136(8):2207-12.
2 Halvorsen BL, Carlsen MH, Phillips KM, Bøhn SK, Holte K, Jacobs DR Jr, Blomhoff R. Content of redox-active compounds (ie, antioxidants) in foods consumed in the United States. Am J Clin Nutr. 2006 Jul;84(1):95-135.
3 Puangsombat K, Jirapakkul W, Smith JS. Inhibitory activity of Asian spices on heterocyclic amines formation in cooked beef patties. J Food Sci. 2011 Oct;76(8):T174-80. doi: 10.1111/j.1750-3841.2011.02338.x. Epub 2011 Sep 13.
4 Schweiggert RM, Kopec RE, Villalobos-Gutierrez MG, Högel J, Quesada S, Esquivel P, Schwartz SJ, Carle R. Carotenoids are more bioavailable from papaya than from tomato and carrot in humans: a randomised cross-over study. Br J Nutr. 2014 Feb;111(3):490-8. doi: 10.1017/S0007114513002596. Epub 2013 Aug 12.
5 Abdel-Aal el-SM, Akhtar H, Zaheer K, Ali R. Dietary sources of lutein and zeaxanthin carotenoids and their role in eye health. Nutrients. 2013 Apr 9;5(4):1169-85. doi: 10.3390/nu5041169.