Study: Dog food has high levels of heavy metals

(CNN)– A new study shows most dog food contains dangerous levels of heavy metals and other contaminants.

According to the non-profit Clean Label Project, dog food has up to 13 times more heavy metals than human food.

That’s a problem because researchers say all those metals could contribute to higher cancer rates.

The worst offender is kibble.

The study didn’t break down foods by brand, but it did say fresh and frozen foods contain less metal than dry.