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Botanicals for Performance

This is an excerpt from Power Eating-4th Edition by Susan Kleiner & Maggie Greenwood-Robinson.

Botanicals for Performance

Herbs are the most popular self-prescribed medication. They now come in capsules, tablets, liquids, and powders. Of the $20 billion spent on dietary supplements in the United States, more than $5 billion is spent on herbal supplements alone. Those sales figures increase by 3 to 5 percent each year. Herbs are heavily promoted as bodybuilding supplements with little evidence that they work (although we have more data now than ever before) Also, herbs can even do harm.

An herb is a plant or part of a plant valued for its medicinal qualities, its aroma, or its taste. Herbs and herbal remedies have been around for centuries. Even Neanderthal people used plants for healing purposes. About 30 percent of all modern drugs are derived from herbs. Cooking with herbs and botanicals is a very powerful way to influence your mind-body health. I encourage you to enhance the healing properties of your foods by adding more herbs and botanicals to your diet. In this chapter, however, I'll be focusing more on supplements. The information in this chapter can help guide you through the often-confusing maze of which herbs can be helpful and which may be harmful.

Natural, but Not Always Safe

It's a common but dangerous notion to think that because herbs are natural, they are safe. What separates plant-derived drugs from herbal supplements is careful scientific study. Makers of herbal supplements in the United States are not required to submit their products to the FDA, so there is no regulation of product quality or safety. Without the enforcement of standards, there is only a meager chance that the contents and potency described on labels are accurate. Some eye-opening proof of this was found in a study conducted at the UCLA Center for Human Nutrition. Researchers analyzed commercial formulations of saw palmetto, kava kava, echinacea, ginseng, and Saint-John's wort. They purchased six bottles each of two lots of supplements from nine manufacturers and analyzed their contents. There were differences in what was actually in the product versus what was stated on the labels, particularly with echinacea and ginseng. Even the product labels varied in the information provided. Dosage recommendations and information about the herbs often varied.

This study reflects an important problem with herbal products. When products that are not standardized are tested for effectiveness, conclusive evidence on what works and what doesn't is hard to come by, no matter how well the study is designed. What you are taking may not be the same in any way as the extract that was tested.

Many herbal supplements are contaminated, too, although this is usually not the case with well-known mainstream store brands. For this reason, try to purchase herbal supplements from reputable manufacturers. Also, make sure the product lists all ingredients on the label and that it is certified by a good laboratory. Given all the time you spend making sure your food is clean and the exercise you do is at peak levels, why unintentionally mess up your health and performance with a dubious supplement?

Herbs are classified as food supplements by the FDA. Labeling them as medicines would require stringent testing to prove their safety and effectiveness. This costs millions of dollars per herb, an investment few manufacturers are willing to make.

Fortunately for consumers, supplements can no longer be labeled with unsubstantiated claims. The latest government regulations require that the supplement industry abide by the same labeling laws that govern packaged foods. This means that any supplement bearing a health claim must support the claim with scientific evidence that meets government approval. Any product marketed as a way to cure, modify, treat, or prevent disease is regulated as a drug by the FDA.

What you see on supplement labels now are structure and function claims. This means that manufacturers are allowed to make claims about the impact of dietary supplements on the structure or function of the body, but these claims must be truthful. An example of such a claim is, “Vitamin C is involved in immune function.”

It's not uncommon to have an allergic reaction to drugs, even those that have been tested and manufactured with strict safeguards. Therefore, it is even more likely that untested herbs, which are consumed in large amounts, may also produce allergic reactions. These reactions can sometimes be fatal. Herbs can interact with prescribed medications, too. If you're taking any medications, you should consult your physician, pharmacist, or dietitian before using any herbal supplement.

In addition, if you're scheduled for surgery and are taking herbal supplements, let your physician know well in advance of your operation. Certain herbs, particularly Ginkgo biloba, garlic, ginger, and ginseng, interfere with normal blood clotting and can lead to excessive blood loss during surgery. Mood-boosting herbs such as Saint-John's wort and kava kava dangerously heighten the sedative effects of anesthesia.

Pregnant and nursing mothers should avoid all herbal preparations. If you are pregnant or nursing, ask your physician or dietitian about specific herbal teas, because even these can cause harmful reactions in a developing baby or nursing infant. Don't give herbal supplements or remedies to children, either. There is virtually no medical information about the safety of herbs for children. Your best intentions could result in serious harm.

Because there's no universal quality-control regulation of the industry, the danger of chemical contamination of herbal supplements is real. Were the plants sprayed with any chemicals before harvesting or processing? Other toxic contaminants or banned or illegal substances may enter the product during processing as well. For instance, a study testing herbal products for prohibited anabolic androgen steroids and GH found that 15 percent contained prohormones (variants of hormones) that were not declared on the label. Most of these substances were manufactured in the United States but were sold in European countries. Products that are purchased by mail order from other countries are even more questionable than those purchased in the United States. The following is a rundown of well-known herbs, either sold alone or as an ingredient in fitness supplements. I have classified these herbs similarly to the way I classified sport supplements in chapter 8. According to current sport science research, some meet their marketing claims, and others are possibly useful. Table 9.2, located at the end of the chapter, provides a quick reference for the effectiveness of the many performance herbs on the market.

Meets Marketing Claims

Much of the research on herbal supplements has been conducted outside the United States, but experts agree that the products listed here have been well tested for efficacy. Even so, herbs can act as powerful drugs. Approach them with the same respect as you would any prescription medication.


Culled from a shrub native to South Africa, the leaves of this herb are usually made into a tea and other supplement forms. Buchu is a mild diuretic, and in that regard it may help rid your body of excess water weight. It is also an antiseptic that fights germs in the urinary tract.

Buchu is generally considered safe, although herbalists recommend taking no more than 2 grams two or three times a day.


Ancient Chinese herbalists swore that this member of the buckwheat family is one of the best longevity promoters ever grown. According to herbalists, fo-ti exhibits different properties depending on the size and age of its root. A fist-sized 50-year-old plant, for example, keeps your hair from turning gray. A 100-year-old root the size of a bowl preserves your cheerfulness. At 150 years old and as large as a sink, fo-ti makes your teeth fall out so that new ones can grow in. And a 200-year-old plant restores youth and vitality. Or so the folk tales go.

Fo-ti has a reputation as a good cardiovascular herb. Supposedly, it lowers cholesterol, protects blood vessels, and increases blood flow to the heart. Fo-ti does act as a natural laxative, however, and in this regard it's probably a safe herb.


Guarana is a red berry from a plant grown in the Amazon valley. It contains seven times the caffeine as coffee beans and is widely sold in health food stores as a supplement to increase energy. It is also found in energy drinks and energy waters. The supplement is made from the seeds of the berry.

Guarana is used in a number of natural weight-loss supplements. It is believed to increase thermogenesis (body heat) and thus stimulate the metabolism. In large doses, guarana may also cause the body to lose water because the caffeine it contains is a diuretic. As for a possible performance benefit, guarana has been shown to increase blood glucose in animals. Whether that holds true for humans, however, remains to be seen. A note of caution: If you're sensitive to caffeine, it's best to leave guarana alone.

Learn more about Power Eating, Fourth Edition.

More Excerpts From Power Eating 4th Edition