Herbal supplements, as well as any compound derived from a plant or food product, are a cocktail of multiple classes of molecules that are all structurally related to one another. A ‘phenolic’ molecule actually refers to a very large group of molecules, and even ‘stilbenoid’ refer to many differing molecules.
Herbs are, by and large, nature’s proprietary blends. They can contain just a single important molecule, with the rest being ‘filler’. Berberine accounts for almost all of the benefits of some of the plants it is found in, for example. Or an herb could contain a variety of molecules, all of which have benefits that are either similar to one another, like those found in Japanese knotweed, or widely different when isolated, as is the case with cinnamon.
Due to the variety of herbs and extracts, we need to pay attention to two unique concepts: standardization and extraction techniques, the former being a bit more important (from the consumer side) than the latter.
Extraction is the process of refining crude powder (crushing up the leaves or stem of a plant, then dehydrating it) into a smaller overall dose, while retaining the molecule of interest. This means you can take a lower dose of the powder and potentially get the benefits of a higher dose.
For a (hypothetical) example, we examine the herb astragalus membranaceus:
20g of the crude root powder each day confers the benefits of the dry powder.
An ethanolic extraction turns the 20g of powder into a residue soluble in ethanolic (2g), and another product that is not soluble in ethanol (18g).
If all of the astragaloside IV was in the ethanolic fraction, then you have successfully concentrated the herb and created 18g of an industrial byproduct.
The above example is what is known as a 10:1 extract, or 10-fold concentrated. From the standpoint of the molecule of interest, a pill dose contains 10 times as much of the molecule, when compared to the crude herb. For example, 100mg of the capsule is considered to be equivalent to 1,000mg of the plant.
Sometimes products have ranges posted, such as 5-7:1. This means that consumption of the herb is in the range of being equivalent to consuming five to seven times as much of the plant itself.
This concentration is important for supplements like tongkat ali, which tends to be taken in a 100:1 concentration (eurycomanone, considered the active ingredient, can be taken in 500mg of the supplement, which is equivalent to 50g of the plant), making consumption of the plant not only extremely expensive, but also impractical.
Extractions are used for two reasons:
To concentrate the desired molecule into a smaller, more practical form
To potentially eliminate undesired ingredients from the supplement
Cinnamon is a good example of the latter, since ‘water extracts’ of cinnamon retain the compounds that benefit glucose metabolism but significantly reduce the levels of some fat-soluble coumarins, which are toxic in high levels. This is why some supplement companies can claim that their extractions are ‘safer’ than others.
Extraction is the process of removing impurities and damaging molecules, while attempting to concentrate the beneficial and desired compounds in the final product.
Standardization is a form of quality control. A supplement that is ‘standardized for 0.8% valerenic acid’ means that regardless of whatever extraction technique used, the final product has the stated content of valerenic acid.
Achieving final standardization by using different extraction processes can result in different products, but in the end they will contain the same levels of the desired molecule.
For example, if the desired molecule in cinnamon is cinnamaldehyde, either a water soluble or ethanol soluble extraction is ideal. The former, however, is considered better due to a lower final concentration of the potentially toxic coumarins.
Standardization is a form of quality control, which assumes one molecule must meet the ‘standard’, a level that supplements must meet to be sold.
What do I need to know about standardization and extractions?
Just because something is standardized or extracted doesn’t necessarily mean it is better, although this is often the case.
There are times when an extraction is not only better, but it is specifically what is used in scientific studies because it’s the best way to access the active molecules. The EGb-761 extract of ginkgo biloba and the WS-1490 extract of Kava are great examples. These are instances of when the processing truly does matter and it makes consumption of a herb more reliable and beneficial.
Other uses are debatable. For example, extracts of many Chinese herbs like astragalus membranaceus exclude the carbohydrate content, due to it being bulky and unfit for pills. Carbohydrates are bioactive, mostly in regard to the immune system, and great examples of this can be found in some immunomodulators (garlic, guduchi, astragalus) or medicinal mushrooms like reishi. Extractions of these plants may not be a good idea, since the process might concentrate more than just the beneficial compounds.
Sometimes processing is done because it is traditional. Cissus quadrangularis is a good example. Cissus is standardized for ketosteroids, but evidence for the benefits of ketosteroids is lacking. The molecule responsible for the benefits seen with cissus supplementation tends to be contained in traditional extraction, but the precise percentage of ketosteroids may be misleading.
Standardization and extractions are the processes through which herbs are prepared for human consumption. These methods allow supplement companies to refine the benefits or reduce the risks of an herbal supplement. Whether or not the processing is beneficial depends on what processes are used and whether they are appropriate for the herb in question.