Final answer:
The estimated cost of mental illness to the Canadian society is significant, although not specifically mentioned in the information provided.
Step-by-step explanation:
The estimated cost of mental illness to the Canadian society is not specified in the given information. However, it is mentioned that in the United States, mental illnesses cost more than $300 billion annually. Since Canada has a similar healthcare system and population size, it can be inferred that the cost of mental illness to the Canadian society is also significant.