Toronto's top doctor is recommending lowering the speed limits on residential city streets to 30 km/h in an effort to cut down on pedestrian and cyclist fatalities.

The recommendations came Monday from Medical Officer of Health Dr. David McKeown in response to a report looking into the benefits and risks of both walking and cycling, which was released to the Board of Health at a meeting on April 2.

McKeown also recommended lowering the limit on all other non-residential streets to 40 km/hr, unless otherwise posted.

A slight change in speed limits would have a huge effect, he wrote.

A pedestrian hit by a car travelling 50 km/hr has an 85 per cent chance of dying. When the car is travelling at 30 km/hr the likelihood of death is reduced to just five per cent.

"Decreasing vehicle speed to 30 km/hr on residential streets and adopting a citywide speed limit of 40 km/hr on all other streets would improve safety for cyclists and pedestrians," McKeown wrote.

The full report Road to Health: Improving Walking and Cycling in Toronto, looked into active transportation, which includes both walking and cycling.

Besides the speed limit changes, McKeown also recommended that the city install leading pedestrian signal intervals, which give pedestrians a head start to cross the road before the light changes for vehicles, as well as additional road markings for cyclists.

The report suggests bike boxes could make cycling safer at intersections. The boxes allow bicycles to stop in front of cars at an intersection, allowing both the cyclist and vehicles to have better visibility.

In an average year, approximately 1,000 cyclists and 2,000 pedestrians report being injured to Toronto Police Services, the report says, noting that this number is likely low since many injuries are not reported.

Besides looking at ways to improve safety, the study also looked into the health benefits of active transportation in Toronto, which include reduced mortality from chronic diseases, and reduced risk of heart attacks, strokes, obesity, diabetes and several types of cancer, particularly colon and breast cancer.

The report estimates that when Toronto residents remain active through walking and cycling it prevents enough chronic illness to save between $110 million and $160 million in health-care costs.

These savings could be further increased by making the city safer for pedestrians and cyclists, McKeown writes.

"By improving safety for pedestrian and cyclists in Toronto the direct costs associated with vehicle collisions with pedestrians and cyclists could be reduced by over $62 million," reads McKeown's summary.

Toronto Board of Health will consider the recommendations at a meeting on April 30 and, if approved, could be debated by city council on May 8.