I ve run at least seven miles a day, 360 days a year, for the past 41 years. I ve only eaten one meal, each evening, 360 days a year, for the past 41 years. Lately I ve noticed a sweet odor to my breath and the same in my nose. I m concerned. Any ideas? Back in the day, I ran between 80 and 100 miles a week, with the same diet.