Yes, it is.
Galvanized Steel is coated with zinc to provide corrosion protection to the steel under layer.
Zinc is a naturally-existing and formed element. Zinc is considered an essential mineral for human consumption and is even included in most single tablet vitamin or mineral supplements. Zinc is believed to have many positive antioxidant properties which play a key role in healing and the operation of several enzymes. Most diets recommend an intake of approximately 12mg of zinc a day for a normal healthy adult.
Although zinc is essential for a healthy body, it can be dangerous if inhaled during the welding process or ingested in large quantities (a common example is eating a large quantity of American pennies).
The amount of zinc that enters the soil from the garden bed under normal conditions is not significant. You may still need to enrich your soil with zinc supplements if you intend to grow certain crops or are using acidic soils.