Protein powders may contain high levels of lead and cadmium, with chocolate-flavored and plant-based products testing at the highest levels, a new report said.

A study conducted by the Clean Label Project found that cadmium and lead were found in many types of protein powders — with organic, plant-based and chocolate-flavored protein powders containing the highest levels of heavy metals.

The over-the-counter protein powders contain a disturbing levels of these foreign elements, and the highest amounts are found in plant-based, organic, and chocolate-flavored products. The toxic elements include lead and cadmium.