Posted on: June 11, 2018

 You’re not the first person to have questions about herbs and herbalism. So, we brought in one of our experts to help answer some of the most common questions and concerns. David Bunting, Herb Pharm’s VP of Botanical Affairs, began studying herbalism in 1979 and has been making herbal medicines professionally since 1982.

Question: How can you tell how much herb is in an herbal extract?

You may be wondering how to figure out how much herb is in your extract. To get started, it’s actually helpful to first rephrase the question. This is because extracts, by their very nature, no longer contain the starting herb. Instead, they contain phytochemical extractives from the herb that are now separated from the structural material of the plant. This is what gives an extract its special properties. So, it might be better to ask, how much herb does the extract represent? Or put another way, how much herb is this extract made from?

The answer to the question lies in the weight to volume strength ratio. Strength ratios describe the weight of the starting herb and the volume of menstruum (combined liquids) used to extract it, and are also known as the extraction rate. So, for example, a 1:4 ratio means 1 gram (g) of herb is extracted with 4 milliliters (mL) of menstruum. You can also divide out the ratio to give 0.250 g/mL, equivalent to 250 mg/mL. And if you multiply this by the dose in mL you’ll get the extraction rate per dose. Here, if the dose is 0.7 mL, you get an extraction rate of 175 mg/dose.

Strength ratios are predetermined for every extract we make and are consistently followed as part of our manufacturing process. And now that you know the background to strength ratios, you’ll be glad to know that our extraction rate per dose is on every label. The “E” in the Supplement Facts Panel refers to a number below the Other Ingredients list clearly labeled as “Extraction Rate.”