Toothpaste by Arm and Hammer Arm & Hammer confirms that its toothpaste is gluten-free. Gluten is a protein found in wheat that can cause issues for people who are allergic or sensitive to it. If you're concerned about whether or not the toothpaste will cause issues for you, then we recommend doing a trial run with just a small amount on your hand first. We also recommend reading the label carefully before buying products that say they're gluten-free because sometimes companies substitute another grain like corn or rice instead.