While walnut growers have long considered the nut part of a healthy diet, new FDA rules have made the label more official. According to the California Walnut Commission, the new definition of healthy foods is progress toward labeling that reflects the most up-to-date nutrition research.

The updated guidelines say Americans should prioritize nutrient-dense foods, including many nut and seed varieties. The Commission highlighted walnuts as an excellent choice for healthy diets, especially as consumers try to avoid saturated fats.

Walnuts largely contain polyunsaturated fats, including an essential fatty acid: omega-3 ALA. They are the only tree nut with significant amounts of that fatty acid.

Read more on walnuts and healthy foods here.