Institute for Optimum Nutrition (ION) is an independent, not-for-profit educational charity based in the UK, dedicated to promoting the principles of optimum nutrition through education, research, and public engagement.

Established in 1984, ION offers accredited training in nutritional therapy, enabling students to become professionally qualified practitioners. Alongside its educational mission, ION provides nutritional support through its clinic and contributes to scientific knowledge with ongoing research initiatives.

The institute is committed to advancing health and well-being by empowering individuals and communities with evidence-based nutritional knowledge.