Plain and simple, “potency” refers to how much of an ingredient a supplement contains. As Ferira explains, “think of ‘potency’ as a dose that carefully considers the ingredient’s daily requirements if known, or science-backed levels.”
In fact, the FDA regulates the term “high-potency,” specifically, stating that products can only call themselves high-potency if they include 100% of the RDI (Reference Daily Intakes), also known as the Daily Value (%DV), for vitamins and/or minerals in them (or more) per serving. In a multivitamin, for example, which contains a variety of vitamins and minerals, at least two-thirds of them have to have a dose of at least 100% of the RDI in order for that multi to label itself as high-potency.
A quick example: If your multivitamin contains 20 ingredients, it has to provide 100% of the RDI of at least 14 of those nutrients in order to tout itself as high-potency. (Unless it wants to land in a lot of hot water, that is.) Ferira concludes, “A singular nutrient or multivitamin/mineral supplement formula that boasts a ‘high-potency’ claim is not marketing. Instead, this special designation refers to intentionally concentrated and effective levels of nutrition.”
A good reason to make sure your multivitamin is truly high-potency? Research shows that more than 30% of adults fall short on eight key nutrients when relying on food alone. About one in three people, meanwhile, is at risk of at least one true nutrient deficiency. Basically, we’re falling really, really short on essential micronutrients, which suggests that a multivitamin with lame doses of nutrients is truly, as Ferira puts it, “weaksauce,” at helping us truly fill the gaps we face.*
The sad reason many multi formulas cut corners on the potency of their ingredients (nutrients and botanical phytonutrients, alike), according to Ferira: to save money or space or both. (Certain nutrients, and particularly premium sources and forms of them, can be expensive and bulky!)