Label muddle
Concentrated, potency, standardized, active. . . . confused? It’s no wonder–interpreting herbal supplement labels is trying, even for experts in the field. Commercial products offer a fast and convenient way to use herbs, but it’s often difficult to determine which herb will meet your needs and how much of it you need to take for it to be effective.
The first step through the maze of herbal supplement labeling is to understand the terms used to describe herb characteristics.
Why standardize?
Plant content varies with season, climate, soil, and other growing conditions. Who hasn’t bitten into a beautiful apple, only to find it dry and tasteless? Apple quality is a direct result of any number of variables, which include not only the amount of sunlight, water, and fertilizer the trees receive, but also harvest and storage conditions. The same holds true for herbs. When one or more of the variables fluctuates, the potency, purity, and activity of an herb also change.
Standardization is a means of reducing variability by specifying the amount of a certain compound or compounds that an herb product contains. For example, many ginseng products are standardized to contain 5 percent ginsenosides; ginseng leaves and root themselves contain anywhere from 1 to 7 percent ginsenosides. Taking a standardized ginseng product guarantees that you get the same amount of ginsenosides in every dose. When you take ginseng in fresh or dried form or in a nonstandardized product, the amount of ginsenosides you receive in each dose can vary considerably.
Standardized products usually contain certain levels of compounds known to indicate biological activity in pharmacological tests. “Active” compounds are those that have been shown to cause a particular effect. “Marker” compounds, although not directly responsible for an herb’s efficacy, nevertheless are always present when the herb has shown its effectiveness during testing, and their presence in an herbal supplement is thus an indication of its effectiveness. (Product labels rarely specify whether the standardized ingredients are active or markers, however.)
Limits
In most cases, only selected compounds of an herb are standardized. Most herbs have been used in their whole form for centuries, and few have been researched thoroughly; thus, the compounds responsible for their health benefits are often unknown. Without scientific studies, no authoritative reference exists to help manufacturers determine the appropriate standardization.
Moreover, testing procedures vary. Tests can measure either classes of compounds (for example, alkaloids) or specific compounds within a class (for example, the alkaloid berberine). And because testing procedures vary from manufacturer to manufacturer, two companies may make different nutritional claims for the same product.
What it doesn’t mean
“Standardized” means that the product is consistent, not that it is concentrated. A product that contains no active compounds can be considered standardized; a standardized herbal product may well contain fewer active ingredients than a whole herb of good quality.
Some product labels guarantee potency level, meaning that the product contains a minimum amount of a compound or compounds. Because their strength is not specified beyond that minimum, such products are not as consistent as standardized products.
“Standardized” also does not mean “complete” or “optimally effective”. Some forms of standardization involve processing that changes the composition of the herb or causes some compounds to be lost altogether. Thus, a standardized product could be less effective than the whole herb. In addition, standardization deals only with certain compounds and not with the composition of the product as a whole, and so consumers should not think of it as a yardstick for determining the product’s complete effectiveness.
What to look for
First, become an informed consumer–research the effects that the herb has been shown to have and identify the active compound or compounds. Then purchase products that clearly and accurately identify the compounds standardized, the concentration, and the amount per dose. Also, don’t be swayed by therapeutic claims. According to the Dietary Supplement Health and Education Act of 1994, a manufacturer is not allowed to claim that a supplement product cures a specific illness, such as the flu, common cold, or cancer. However, because many manufacturers make semi-therapeutic claims, your best bet is to do your research ahead of time to avoid being swayed by marketing claims.
A Glossary
Below are definitions of words occurring in articles in this issue of Herbs for Health.
Refer to this glossary if you come across words you’re not familiar with as you read.
alkaloid: one of a large group of nitrogen-containing alkaline substances found in plants; usually very bitter and usually contains active compounds that may affect health
anemia: a deficiency in red blood cells, hemoglobin, or blood volume
anti-inflammatory: an agent that counteracts inflammation, a response of the body to injury marked by swelling, redness, pain, and heat
antimicrobial: an agent that kills or inhibits the growth of microorganisms, such as bacteria and viruses
antioxidant: an agent that controls free radicals, substances that damage cells by oxidation
aqueous extract: an extract prepared with water
astringent: a substance that can contract the skin or shrink the mucous membranes
bioavailability: the degree and rate at which a substance such as a drug is absorbed into a living system or made available at a site of physiological activity
bioflavonoid: any of the flavonoids (a class of substances widely found in flowers, leaves, and fruits) with biological activity in mammals
colic: spasmodic pain in the abdomen
crossover trials: clinical trials in which subjects are exposed first to one treatment then the other in random order
decoction: extraction of the soluble constituents of tough plant material such as bark or woody twigs by boiling
emmenagogue: an agent that promotes menstruation
expectorant: a substance taken to promote the expulsion of phlegm from the respiratory tract
gingivitis: inflammation of the gums
ginsenosides: active compounds (eleven major, nineteen minor) found only in ginseng that are responsible for its health benefits
hemostatic: an agent that checks bleeding
hypertension: high blood pressure
infantile seborrheic dermatitis (cradle cap): a mild skin disorder of children caused by overactive sebaceous glands or in some cases by the yeast Pityrosporum ovale
inflammation: a response of the body to injury marked by swelling, redness, pain, and heat
infusion: extraction of the soluble constituents of fresh or dried herb material by pouring boiling water over it and steeping it, covered, to the strength desired
insomnia: inability to obtain adequate sleep
linoleic acid: an essential fatty acid occurring in many vegetable oils that is used in the formation of prostaglandins
linolenic acid: an essential fatty acid occurring in some fish oils and many seed oils that is used in the formation of prostaglandins
periodontal disease: a disease of the supporting structures of the teeth
placebo: an inert or innocuous substance that is given to the control group in a clinical trial to test the efficacy of another substance, such as an herbal treatment
poultice: a soft, usually heated herb or other preparation that is wrapped in a cloth and applied to the skin
prostaglandins: hormone-like chemical messengers, secreted by most body tissues, that perform varying functions, such as controlling blood pressure or smooth muscle contraction
randomized, double-blind, placebo-controlled study: the most rigorous test in hard science. Subjects are randomly assigned to one of two groups. Members of one group receive the substance being tested; the others receive a placebo. Neither the researchers nor the subjects know who is getting the test substance until after the study has been completed.
saponins: various glucosides occurring in plants that produce soapy lather
sebaceous gland: a gland in the skin that secretes sebum, a fatty substance that lubricates the skin
sedative: an agent that reduces anxiety and tension
squamous cells: scaly or plate-like cells found on the body’s surface and lining its cavities
therapeutic: relating to the treatment of a disease or disorder; curative
tonic: a substance that invigorates, restores, or stimulates
varicose veins: abnormally swollen, dilated veins with weakened valves that allow blood to remain in the lower limbs
wheezing: a whistling sound caused by difficult or obstructed breathing