Science-Based Nutrition Dietary Supplement Helps Maintain Healthy Joints Non-GMO / Gluten Free / Soy Free Doctor's Best Glucosamine Sulfate contains sodium-free, potassium stabilized glucosamine sulfate. Glucosamine sulfate consists of glucosamine, an amino sugar extracted from shellfish skeletons. Thoroughly researched for decades in human clinical trials, glucosamine sulfate supports normal, healthy joint function and helps maintain healthy joints. Most clinical studies on the effectiveness of glucosamine have been conducted using glucosamine sulfate. Helps support normal healthy joint function Helps maintain healthy joints