Saturday, 7 February 2015

Herbal medicine

Herbs have been used in all cultures as medicines and some have real medical benefits. but care has to be taken with herbal cures as they are poorly regulated.

In historical times, herbs played a major part in our medical treatment, though as early as the 17th century, when herbalist Nicholas Culpeper published his Complete Herbal, there was a debate between the proponents of herbal and chemical medicine. With a modern understanding of the active ingredients in herbs we can see that the distinction is artificial. Herbs are an effective source of chemicals that have an active effect on the human body, though often this effect is improved if the chemical agent is refined and modified.

So, for instance, willow bark, containing a chemical called salicylic acid, has been used to help reduce pains and fevers for at least 4,000 years. Unfortunately salicylic acid causes sharp stomach pains and can cause internal bleeding – so that relief came with a price. At the end of the 19th century, the German pharmaceutical company Bayer produced a painkiller called aspirin, which modified the active ingredient to the much less aggressive acetylsalicylic acid. The active ingredient of medical herbs has been repeatedly isolated and improved. Quinine for malaria, atropine and digitalis for the heart, for instance, all originated with herbal cures, but are much better and safer in their pure chemical form.

Herbal medicine has a strong presence in China, and there are herbal medicine stores on many of our high streets. Unfortunately, current herbal medicine still uses theories with no basis (such as employing a herb with the same shape as an organ of the body to treat that organ) and has rarely advanced. There are also well-documented dangers in taking herbal medicines at the same time as other medications. It is always worth checking with your doctor first.

The popular herbal treatment St John’s Wort, for instance, which has proved effective in helping with mild depression, has as many possible side effects as any prescription drug, from gastrointestinal pain to dizziness. It can cause serious problems with anti-HIV, anti-cancer drugs and contraceptive pills; plus it generally reduces the effectiveness of the transport mechanism carrying drugs into the bloodstream. Because of this it has been banned in France. You can’t assume that because a treatment is herbal it is safe in all circumstances.

Another significant problem with herbal treatments is that a herb rarely contains only one active ingredient – and it is almost impossible to give a well-controlled dose, as the amount of the chemical in a herb will vary from plant to plant. Where a prescription medicine will have isolated the useful chemical, in a herb you could be exposing yourself to a whole range of potentially unpleasant substances to get the beneficial one. But more worrying still is the reality that there is very little regulation of the quality of herbal medicines.

A major US study in 2013 analysed 44 processed herbal prod- ucts and 50 medicinal herbs from a range of suppliers. The results were shocking. Less than half of the products actually contained the labelled main ingredient. Nearly 60 per cent contained herbal species that weren’t listed on the ingredients. A third also contained fillers and contaminants that weren’t on the label. In three of the companies tested, none of the products contained what they said they did. In other studies, herbal medicines have been found to be contaminated with dangerous heavy metals and other extremely poisonous substances.

*UPDATE* In February 2015 the New York State attorney general's office accused four major US retailers of selling herbal supplements that were fraudulent and in some cases were contaminated with unlisted ingredients. These weren't backstreet herbalists, but Walmart, Walgreens, Target an GNC. Approximately four out of five products didn't contain any of the herbs on their labels. Many contained little more than rice and houseplants.

The products with non of the herb in included Gingko Biloba, St. John's Wort, Ginseng, Echinacea and Valerian Root. Typical fillers were rice, asparagus, wheat or grass and garlic, though oddly many of the samples actually claiming to be garlic had none in. This really emphasises how much you are at risk of getting anything but what you expect when buying herbal remedies.

So, while there are certainly benefits to some herbal remedies, the lack of a proper regulation and of a testing regime paralleling that used on conventional medication means that there will always be significant risks attached.

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