Heavy Metal Contamination of Powdered Protein and Botanical Shake Mixes

The increasing popularity of powdered shake mixes as nutritional supplements or convenient meal replacements, combined with the complex formulations incorporating multiple ingredients of unknown origin in many of these products, might pose public health risks because of possible contamination with harmful substances such as heavy metals. Our aim was to determine levels of four heavy metals in a select group of popular powdered protein and botanical shake mixes purchased from local stores specializing in sales of whole/organic foods. To measure levels of arsenic, cadmium, chromium, and lead, analyses using inductively coupled plasma dynamic reaction cell mass spectrometry were performed. In 56% of the products individually tested, metal levels for one daily serving exceeded the daily thresholds and standards recommended by various regulatory agencies, particularly for rice-based shakes. This study highlights that commercial shake mixes can be a significant source of exposure to toxic heavy metals and emphasizes the need for consumers to limit their exposures to these metals.