Hi All, 
The citation I couldn't find yesterday is:

Kwan RM, Thomas S, Mir MA.  Effects of a low carbohydrate isoenergetic diet
on sleep behavior and pulmonary functions in healthy female adult humans.  J
Nutr.  1986 Dec;116(12):2393-402.  

It was a study of healthy women (student nutritionists) that reported a 5%
increase in peak flow and a 10% improvement in pulmonary function after one
week on a low carbohydrate diet. 

When I tried it for one month, I got an increase of almost 30% in peak flow,
but my peak flows are quite variable for reasons I don't fully understand so
there may be some confounding variables at work here. 

Best Wishes, 
Ron