About the Author
JAMES A. DUKE, PHD, held several posts in his more than three decades with the US Department of Agriculture, including chief of the Medicinal Plant Resources Laboratory. He is the author of numerous scholarly and popular books, including the bestseller The Green Pharmacy, and is on the board of advisors for Prevention. He resides in Fulton, Maryland.
Excerpt. © Reprinted by permission. All rights reserved.
CHAPTER 1
How Foods Heal
"Medicinal Foods" through the Ages--From Ancient to Modern Times
If you're familiar with my Green Pharmacy (or Farmacy, as I like to call it), you probably think that it's all about herbal remedies. That's partially true. Herbs have always been near and dear to my heart, and they still are. However, research over the past few decades has taken the Green Pharmacy in a new and interesting direction--away from the health food store and into the supermarket.
A growing body of literature indicates that a number of plant foods-- fruits, vegetables, spices, and even beverages--offer many of the same healing powers that you'll find in herbal remedies. Foods, however, have a distinct advantage over their herbal cousins: Instead of depending on capsules, tinctures, and teas, you can incorporate foods into delicious, flavorful meals that are as satisfying as they are healing!
Of course, we all know that fruits and vegetables are healthful. That's why the government recently increased its recommendation from five servings to nine a day. But only now are we learning just how healthful they really are. To begin with, they're high in fiber, low in calories, and devoid of or low in harmful fats. But that's not all. Most have hundreds, if not thousands, of medicinal com£ds, each of which has a specific impact on your health and well-being. As a result, you can choose to add various plants to your diet to treat certain ailments. For example, I eat celery almost every day to prevent the pain associated with gout, and garlic is part of my diet because I know it can benefit my heart and possibly even help control my chronic Lyme disease.
Over the next few pages, I'll give you some background on how plant foods heal, so you can gain a greater understanding of their role in your health. Then, in the chapters to come, I'll help you plan your own regimen to treat specific conditions with specific foods.
Food as a Historical Healer
The idea of "food as medicine" is hardly a new one. In fact, when you consider that ancient man lacked the technological capability of today's chemists, it only makes sense that their medicines came directly from nature.
In fact, evidence of using food to heal dates back thousands of years. Ayurveda, the traditional healing art of India, is a perfect example. It borrows many of its ideas from Hinduism, incorporating multiple therapies that include herbs, massage, and meditation. Ayurvedic practitioners may even go so far as to try a new diet to prevent or treat specific conditions. One medicinal food from Ayurveda may be familiar to you: turmeric, which often shows up as a spice in Asian cuisine. Aside from its unique flavor, turmeric may also prove a helpful treatment for people with arthritis, Alzheimer's disease, and some forms of cancer. Although the research evidence isn't yet conclusive, it's certainly highly suggestive, and my own experience using turmeric as an anti-inflammatory has been extraordinarily positive. (For more information on turmeric, see page 28.)
Ayurveda, also commonly referred to as Traditional Indian Medicine or Traditional Ayurvedic Medicine (TAM), shares this focus on food with another ancient form of medical practice, Traditional Chinese Medicine (TCM). TCM works from the concepts of "yin" and "yang," which in ancient Chinese philosophy refer to the two fundamental forces in the universe--the aggressive, hot, go-get-'em force (yang); and the passive, lie back and chill out force (yin). You get sick when these two forces fall out of balance in your body.
By now you're probably wondering what all of this has to do with food. In TCM, the foods you eat are seen as having yin properties--cooling and moistening--or yang properties--warming and drying. Depending on the condition you have, your practitioner will help you make food choices to restore balance between the two forces. For example, if you have a mucus- producing cough from a cold, your balance is skewed toward the yin, so you'll want to treat it with warming, drying foods like ginger tea and hot vegetable soups. As you can see, we borrow some of our ideas for treating illness from the Chinese, whether we're aware of it or not!
Better Living through Chemistry?
TAM and TCM are a far cry from Western medicine, which views food as the source of nutrition but ignores its healing properties almost entirely. That's not to say the American view of the diet--seeking a balance among protein, carbohydrates, and fat--doesn't make sense. It does. But it's limited--very limited.
The Chinese and Indian approaches basically say that the body will react in certain ways to certain foods. After all, we have co-evolved with and made use of the plants in our environment throughout the history of our species, so it only stands to reason that we would develop special relationships with some of them, as we have with members of the animal kingdom.
Now contrast that with our notion of modern medicine, which I like to call "better living through chemistry." Most synthetic drugs have been in use for only a few decades rather than a few thousand years, so the body just isn't used to handling them as it handles foods.
What's more, most plant foods contain thousands of bioactive com£ds, each of which plays a unique role in the body. By contrast, the viewpoint of modern medicine is that we're looking for one "silver bullet," the so- called active ingredient--and all the other helpful com£ds in any specific plant are tossed out and forgotten.
I'm not saying that all drugs are bad. In fact, quite the opposite is true: Drugs have saved the lives of many people. But it's tough to argue with the numbers: In 2005, pharmaceuticals killed at least 140,000 people in the United States--that we know of. The number may be even higher. As far back as 2002, the esteemed Journal of the American Medical Association recognized this problem, calling adverse drug reactions "a leading cause of death in the United States."
Now compare that with herbs and supplements. Altogether, they caused an estimated 29 deaths in 2005. The numbers speak for themselves.
The purpose of this book is not to scare you away from taking your medicines. After all, I need to take pharmaceuticals myself every now and then. Rather, what I'm hoping you'll do is "think outside the pillbox" and realize that by taking a different approach to what you eat, many conditions--and the medicines needed to treat them--can potentially be avoided completely.
The Supplement Scare
As you've already seen, supplements have proven safer than pharmaceuticals. However, this doesn't necessarily place vitamin supplements beyond criticism. Their effectiveness, most notably that of the "big three" antioxidants--vitamins A, C, and E--has come into question in recent years.
In the recent HOPE (Heart Outcomes Prevention Evaluation) study, more than 10,000 heart disease patients received either 400 IU of vitamin E or a placebo every day for six years. At the end of the trial, the researchers concluded that vitamin E really didn't do much better than the placebo at preventing death or other adverse outcomes from heart disease.
Vitamin C is generally considered safe even at high doses (though more than 1,200 milligrams can cause diarrhea in some people). But recently, the effectiveness of "megadosing" with vitamin C for illnesses like colds and flu has come under some fire. As the National Institutes of Health points out, more than 30 clinical trials with more than 10,000 participants have looked into the role of vitamin C in preventing colds, and no significant reduction has been noted. Vitamin C supplements may play a role in reducing the duration of colds, however.
Vitamin A (which exists in foods in the form of pre-vitamin A as well as carotenoids such as beta-carotene) has also been studied in supplement form, and it has shown some effectiveness for some conditions. The evidence indicates, however, that if you smoke or drink alcohol, you may want to steer clear of supplementing with pure beta-carotene, since it could actually increase your risk of lung damage, including even lung cancer.
Again, none of this is meant to scare you away from supplements. Quite the contrary; I take a number of them, and I think that multivitamins are a great means of getting a full complement of healthy nutrients in an economical way. I just find it interesting that when a single, specific bioactive com£d is isolated, whether in a pharmaceutical or a supplement, the result is never as dramatic as people expect. That's because in nature, the com£d works in combination with many others to bring healthful benefits to the body. Those combinations exist in only one place--whole foods!
The Food Renaissance
In recent years, you've probably noticed that you're hearing less about familiar nutrients, such as vitamins A, C, and E, in nutrition news and more about exotic-sounding ones, such as lycopene, quercetin, and resveratrol, to name a few. The reason is simple: Researchers are beginning to look beyond the macronutrients in foods, and they're discovering micronutrients and phytochemicals.
Some of the benefits these com£ds offer stem from their antioxidant potential. In the simplest terms, antioxidants help your body by neutralizing free radicals, unstable oxygen molecules that the body can overproduce after exposure to toxins such as cigarette smoke, pollution, and even unhealthful foods. Beyond their antioxidant potential, many com£ds help specific parts of the body remain healthy as well. Beta- carotene, lutein, and cryptoxanthin are good for your eyes. Phytoestrogens fight cancer. Capsaicin attacks arthritis pain. The list goes on and on.
The practical result of these new research discoveries is clear: Emphasis is shifting back to eating lots of healthful whole foods, particularly fruits and vegetables. And when the USDA plays along (which they did in 2005 by increasing their recommendation to nine servings of fruits and vegetables a day), you know we're making progress.
As I said earlier, I believe you can specifically tailor your diet to prevent or even reduce the symptoms related to a number of specific medical conditions--conditions as benign as a flaky scalp or as serious as a heart attack.
We'll have plenty of time to go over all these foods and the conditions they treat in the chapters ahead. First, though, let's look at an overview of some of the "heavy hitters" of the nutrition world as well as a rundown of some cutting-edge cures that we've only recently learned about.
What's Hot in Foods Now
When it comes to nutritional stars, it's funny how certain nutrients seem to go in and out of fashion. For a while, vitamins A, C, and E were hot. Now omega-3 fatty acids, lycopene, and vitamin D are getting all the attention. Next month, it may be something else.
However, just because a nutrient slips out of the limelight doesn't mean that it's no longer important to your health. Here's a quick look at some of the most important ones, from the old standbys to the new stars.
The Old Standbys
Though their reputation has taken a bit of a hit, it's still important to start any discussion of healing foods with the "big three" antioxidants-- vitamins A, C, and E.
Arguably the most famous of the three is vitamin C, found in abundance in foods like bell peppers, papayas, strawberries, and oranges and other citrus fruits. Some exotic fruits, like acerola, camu-camu, and emblic, rarely available in North American supermarkets, may be richer in C. In studies, vitamin C has been linked to the prevention of a number of diseases--most notably heart disease but also some cancers. As a matter of fact, the USDA phytochemical database lists nearly 100 activities for vitamin C, and I could probably double that number in a few minutes of surfing the Web. Research has shown that vitamin C may work more quickly than other antioxidants, blocking free radicals before others even arrive on the scene.
Another significant heart helper is vitamin E, which has reduced the risk of heart disease in a number of studies. This nutrient, found in vegetable oil, sunflower seeds, nuts, and sweet potatoes, has also shown that it may help fight off lung and prostate cancer. Some evidence indicates that vitamin E is even more effective when consumed with vitamin C, reinforcing the idea that eating a variety of fruits and vegetables gives you the most benefits.
Finally, we can't overlook vitamin A. It has gotten its fair share of bad press in recent years, and some studies have even linked it to increased risks of heart disease and cancer. However, it's important to remember that these studies looked at high doses from supplements. The main source of this antioxidant available from foods is beta-carotene, which your body converts into vitamin A. When people stick to the amounts of beta-carotene present in orange and yellow foods such as carrots, squash, cantaloupe, and sweet potatoes, the antioxidant is considered quite healthful.
Naturally, these aren't the only important nutrients, and they're not the only ones I focus on in my own regimen. A lesser-known but equally important antioxidant is selenium (just three Brazil nuts supply a whopping 200 micrograms). The whole range of B vitamins may play a role in preventing the symptoms of neuropathy, a common nerve disorder, and some studies suggest they can treat or prevent Alzheimer's disease. And I focus on getting plenty of magnesium to prevent nighttime leg cramps.
Here again, it all comes back to focusing on a variety of foods to get a balanced intake of all the important nutrients! You can go to the USDA phytochemical database (www.pl.barc.usda.gov/usda_chem/achem_home.cfm) and search for the richest sources of thousands of nutrients and phytochemicals.
The Right Kinds of Fats
Aside from abundant amounts of antioxidant nutrients, the other thing that plant foods have going for them is that they're relatively devoid of the type of fat found in red meat and dairy products, which can harm your heart; and some have fats that are actually good for you. Certain nuts, olive oil, and avocados, for example, have monounsaturated fats, which seem to raise levels of "good" HDL cholesterol while leaving "bad" LDL and total cholesterol levels unchanged.
Another group of beneficial fats currently getting a lot of attention are the omega-3 fatty acids. Though fatty fish like salmon and tuna are usually cited as the best sources of omega-3's, the fish actually acquire them by eating primitive plant forms such as algae, which manufacture these acids.
There is a handful of rich plant sources that provide an omega-3 called alphalinolenic acid (ALA), which can offer some but usually not all of the health benefits of the "fishy" omega-3's. Flaxseed and hempseed have omega- 3's, specifically ALA, in abundance, but a tastier plant source is walnuts. (For more on walnuts, see page 29.)
Recently I learned that chia, of Chia Pet fame, is even richer in ALA. I'm having an Amazonian acquisition, called Inca peanut (Plukenetia volubilis, not related to the real peanut, Arachis hypogaea), analyzed as another contender. And in my Green Farmacy Garden, there's a weed that many Asians consume with sushi. It's called perilla, and it has more ALA than the better-known flaxseed.
The New Stars
