Many medications used today began as plant materials. Digitalis is extracted from foxglove to treat the heart, quinine from cinchona tree bark for malaria, and taxol, an anti-tumour drug, comes from the bark of the western yew tree. All have potential side effects.
Illegal drugs can also be harvested from plants. Opium comes from poppies, and cocaine from the leaves of the cocoa plant. Certainly these natural substances are capable of doing harm. Calling a product ‘natural’ does not mean it will not react with other medicines or that it is free of harmful side effects.
The terms ‘natural,’ ‘alternative’ and ‘complementary’ suggest that these products can be used instead of or without regard for prescription medicines. Like conventional medication, natural medicines have side effects and react with other substances.
Since plant materials are being used, the strength of natural medicines varies depending on growing conditions. The amount of rain and sun, where a plant is grown, when it is harvested, the portion used, length of storage and type of processing all affect the final product.
The term standardized on the label refers to the strength of that specific ingredient. However, the standardized ingredient may not be that which gives the benefits. The benefits might actually come from multiple ingredients within the plant.
Canada’s new Natural Health Products Directorate is now phasing in regulations for natural health products. Since January 2006, all manufactures, importers, packagers and labellers of natural products are required to have a license and use proper manufacturing practices. By the end of 2009, all natural health products must be licensed.
These regulations will help ensure that quality products reach consumer shelves. The labels of licensed products will provide information on dosage, length of use, ingredients, the part of the plant used, risks and cautions.
The new regulations will allow health claims to be made on the labels. If there is no scientific evidence available, these claims can be based on traditional references, which may indeed be folklore.
Before trying any natural product, research it thoroughly. Consider the evidence you find. Did just one study show an effect? What influences on blood glucose were not controlled in the study? How many people participated, for how long, and at what dose? What were the side effects? Studies on natural medicines are often poorly designed and based on only a few patients. Such studies are often done for too little time to offer clear evidence of long-term effectiveness. Think about where information comes from and what products are sold by the source.
Be critical of headlines. Sound health advice is generally based on research over time, not a single study touted by the media. Question quick fix results that are not based on scientific research and established dietary guidelines. Learn to spot unlikely claims. Remember, if something sounds too good to be true, it probably is. As well, natural products are often expensive.
If you do decide to try a natural medicine, inform the health care team who work with you to control your diabetes. Make certain the product will not interfere with your prescription diabetes medication before starting it. Use the product along with, not instead of, prescription medication. Once you start using it, check your blood glucose frequently to see whether it is effective.
Try to use single ingredient products rather than combinations. With a combination product, you cannot know which ingredient is helping or harming you.
Check products at the website quackwatch.org for health fraud.
Canadian Health Network, Public Health Agency of Canada - Using the Topics area on the left-hand side, select the Complementary and Alternate Health section, and choose language.
Natural Health Products Directorate, Health Canada - do a keyword search using ‘Natural Health Products’.
Mayo Clinic drugs and supplements index - select ‘Drugs & Supplements’ on the top menu bar.
American Diabetes Association position statement on unproven therapies - search ‘Position Statement Unproven Therapies’.
American Diabetes Association - search ‘Step-by-Step Approach to Complementary Therapies’
US Food and Drug Administration
Search ‘Tips for the Savvy
Although you may hear certain natural products promoted for those with diabetes, keep the following in mind before using them.
A study of only 60 patients for 60 days brought cinnamon into national headlines. Cinnamon is thought to improve the action of insulin. It is considered safe in the amounts found in food. You might consider sprinkling one-quarter to one teaspoonful of the cassia type on your food daily, while continuing with your usual medication. Monitor your blood glucose more closely to see whether the cinnamon has any effect.
Another common spice promoted as a natural medicine for diabetes is fenugreek (Trigonella foenumgraecum). Fenugreek is thought to affect carbohydrate absorption and improve the use of glucose. While it is considered safe in the amounts normally found and used in foods, it is not safe for children and pregnant women. Avoid it if you have a peanut allergy.
Bitter melon (Momordica charantia, balsam pear, karela) is also thought to improve the body’s use of glucose. This vegetable is used in India, Africa and Asia. It has caused liver damage in animals, and one case of hypoglycaemic (low blood glucose) coma in a child has been reported. It also stimulates menstruation and miscarriage, and should not be used by children or pregnant women.
Products such as glucomannan (konjac), nopal (Opuntia streptacantha, prickly pear cactus) and aloe vera gel are thought to work because their high fibre content slows digestion and improves the body’s sensitivity to insulin. Be aware these have a laxative effect. If the laxative effect goes on too long, the body’s electrolyte balance can be disturbed. (Electrolytes are essential for normal function of the body’s cells and organs.) Aloe vera juice should be avoided, since the laxative effect is often lengthy and intense. It can make Crohn’s disease and ulcerative colitis worse.
Ginseng studies have shown two results – no effect and some effect on blood glucose. Ginseng may slow carbohydrate absorption and improve how the body uses glucose. It can interact with several prescription medications. Side effects include nervousness, excitability, insomnia, headache, and high blood pressure. Limit use of ginseng to less than three months, as it may affect the body in similar ways to the estrogen hormone.
Banaba (crepe myrtle). One 10-person study showed some effect on blood glucose. Banaba may improve how the body uses glucose. Doses between 8-48 mg have not had any side effects.
Holy basil (Ocimum sanctum), and ivy gourd (Coccina indica) have not been proved effective, nor have side effects been reported.
Chromium is probably worth a try. Chromium is only thought to work if you lack it, but tests to check chromium levels are expensive. Chromium is necessary for the body to form a substance called glucose tolerance factor (GTF), which helps in glucose metabolism. Since GTF is only formed in the body, the term GTF on packaging means nothing. The usual dose is 100 mcg of the picolinate salt twice daily. Monitor your blood glucose to see if it has any effect. If not, stop using it.
Bilberry leaf (Vaccinium myrtillus) has been mentioned in folklore as a diabetes treatment. If it has any effect at all, it is probably due to the high chromium content of the leaf.
The use of the trace mineral vanadium is not recommended, as it accumulates in bones, kidneys, lungs and liver. As well, the doses sometimes suggested are well above the 1.8 mg/day recommended maximum intake. It causes abdominal discomfort, gas, nausea, diarrhea, and greenish discoloration of the tongue. Prolonged high doses may cause kidney damage.
You may see these and other ingredients listed on natural products suggested for diabetes. Remember traditional references may be the source for health claims, not scientific research.
You may decide to try a natural medicine after researching it. If so, use your blood glucose monitor as a tool to evaluate the effectiveness of the product. Monitor your blood glucose more often, write down results, and note any side effects. Discuss the results with your diabetes health care team. They are available to help, so work with them and keep them informed.