High radon across much of the state and a gray, low-sun winter.
Much of Ohio sits in EPA's highest radon zone, so testing your home matters here. Winters are cold and cloudy, with a sun too low to make much vitamin D.
Radon is an invisible, odorless radioactive gas that seeps up from soil into basements and lower floors, and it is the leading cause of lung cancer in people who don't smoke. EPA's map puts most of western and central Ohio in Zone 1, its highest-risk category. Neighbors' results don't predict yours, so test your own home.
Your skin makes vitamin D from the sun's UVB rays, and the winter sun sits low. A classic study found no vitamin D made in skin from winter sunlight in Boston (42 degrees north) from November through February, while sunlight at 34 degrees north still worked. Ohio lies between them, near the northern end, so winter sun is a weak source and food matters more.
Ohio winters bring freezing temperatures, snow and ice. Frostbite and hypothermia are risks during outdoor work or a breakdown, and icy surfaces cause falls.
Tell your doctor about long-term radon exposure, especially if you smoke or used to, and see one for a cough that won't go away. Get care for numb, hard or waxy-looking skin after cold exposure.