HERBAL REALITIES
AUTHOR WEIGHS PLANT REMEDIES BY SORTING OUT SCIENTIFIC STUDIES
Mary Beth Faller, The Arizona Republic
When Holly Phaneuf was a little girl, she wanted to make magic potions.
"I would put plants in a pot and stir them around and imagine they would make me fly," she says.
Now a biochemist, researcher and teacher in Utah, Phaneuf is still fascinated by the power of plants.
"But I have more realistic goals, like calming gas pains with chamomile rather than flying."
Plants have been used as medicine for thousands of years, but Phaneuf wanted to know whether traditional herbal remedies could really stand up to hard scientific scrutiny.
There are many studies on plant-based treatments, she says, but few of them are well designed, with a control group that uses a placebo. Many of the studies were done in Europe, where scientists are more open to the idea of alternative medicine -- "and more loose in their conclusions," Phaneuf says. And some of the good studies were done on cells in a test tube or on animals, but not people.
But Phaneuf dug through thousands of studies, in dry scientific journals, to sort through the best ones with the most significant results. The outcome is her book Herbs Demystified (Marlowe & Co., $21.95 paperback), released a few months ago.
Many people think of "herbs" as kitchen seasonings -- parsley, sage, rosemary and thyme. But Phaneuf expands the term to include all plants. She covers cranberries, soy and tea along with sage, evening primrose and black cohash.
Phaneuf's book looks at what the plants do (or are purported to do) at the molecular level, written in a lively, understandable way.
"Plants make all these extra chemicals to protect themselves because they can't run away," she says. "They have to protect themselves from radiation and insects. We can usurp these chemicals by consuming them."
People think plants are good because they are "natural." "And when we think of 'natural,' we think, 'How can it hurt us?' But there's poison ivy and snake venom and things that do hurt us.
"And the line between natural and synthetic can be blurry. If you take plant chemicals and purify them, many of them are identical to the drugs we take. The statin drug Lovastatin is identical to red yeast extract."
And plants should be treated with the same care as medicine, she says. Licorice root protects the stomach lining with the same molecule that can raise blood pressure dangerously, so it should be off limits to anyone with hypertension.
Herbs Demystified covers all versions of each plant, including supplements, which Phaneuf generally avoids because they are not regulated for purity.
After poring over all those studies, Phaneuf says she really wanted to find out whether these plants worked. Some, such as soy, tea and flax, have support from good studies. Others haven't held up to scrutiny.
"Echinacea has been disappointing," she says of the cold treatment. "There are several hundred studies in people, not to mention animals and cells. When you pare it down to the very best, it all looks pretty sad.
"The most reliable thing that echinacea will do is give you a rash."
Holly Phaneuf, a biochemist, tackles common and beloved herbal treatments in her book, Herbs Demystified (Marlowe & Co., 2005, $21.95 paperback). Here is an abbreviated version of what she's researched about some of these herbs and whether they really work:
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Herb
Aloe gel
What it's used for
Applied topically, aloe gel is used for wound healing.
How it works
Aloe gel contains long chains of sugar molecules that attract water, keeping a wound moist. The gel also contains beta-sitosterol, which speeds blood-vessel growth, and a glycoprotein, which inhibits swelling and pain perception.
You should know
Aloe is really two products -- aloe gel and aloe latex, which have very different properties. The best source of aloe gel is the plant itself, rather than a packaged product.
Bottom line
Studies are not conclusive that aloe gel speeds wound healing. It probably helps minor injuries, but could delay healing of deeper wounds.
Herb
Chamomile
What it's used for
Taken internally, chamomile is used as a calming agent and digestive aid. Some people apply it externally as a topical anti-inflammatory.
How it works
Chamomile has molecules that, like Valium, slow receptors on nerve cells when it is consumed, though this has been tested only on rodents.
You should know
If you want to make your own chamomile tea, use preparations made entirely of flower heads rather than stems and leaves.
Bottom line
Chamomile's calming effects have been tested extensively on rodents, but not people. Its anti-inflammatory mechanisms have not been well studied in people. It's safe unless you're allergic to it.
Herb
Cranberry
What it's used for
Cranberries have been touted since the 1920s as a way to prevent urinary-tract infections.
How it works
Scientists used to think cranberry juice worked because it made the urine too acidic to support bacteria, or it was itself an anti-bacterial. Now, they know that cranberries contain molecules called proanthocyanins, which prevent the bacteria from sticking to the walls of the urinary tract.
You should know
Cranberries have been suggested as a way to prevent or treat kidney stones, but because they contain a lot of oxalate ions, they can make the situation worse.
Bottom line
There is evidence that red cranberry juice (not white) and supplements are effective at preventing urinary-tract infections.
Herb
Parsley
What it's used for
Taken internally, parsley is used as a diuretic, digestive aid and laxative. Chewed, it's a breath freshener.
How it works
Parsley inhibits cells' sodium-potassium action, allowing more water to enter the kidneys or colon and producing a diuretic or laxative effect.
You should know
In the 19th century, pure parsley oil was sold as a way to "bring on the flow of menses" -- a euphemism for an abortion agent. Pure parsley oil should be avoided -- the apiole in it can cause anemia and liver and kidney failure, and can cause uterine contractions resulting in miscarriage.
Bottom line
Parsley used as a green, either raw or cooked, is nutritious, and you might experience a mild laxative or diuretic effect. Parsley pills don't freshen breath, but chewing a sprig helps.
Herb
Turmeric
What it's used for
Eaten, turmeric is used as a digestive aid, anti-inflammatory, anti-rheumatic and stimulant. Turmeric powder, extract or oil is applied to ease wounds, bruises and itchy skin.
How it works
The oily yellow pigment, called curcumin, relaxes muscle contractions, which is why it's known as a digestive aid. Curcumin is also a free-radical scavenger, eliminating damaging cells and reducing inflammation. Turmeric also diminishes inflammatory agents in the body.
You should know
People with gallbladder problems should avoid turmeric, which causes the gallbladder to contract, and possibly causes impacted gallstones.
Bottom line
Some studies, including one in which participants' ulcers cleared up, confirm turmeric's effectiveness. Animal studies have found curcumin prevents cancer of the skin and digestive tract. |
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Copyright (c) The Arizona Republic. All rights reserved. Reproduced with the permission of Gannett Co., Inc. by NewsBank, inc.
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