* Gallons of air taken in per...

* Gallons of air taken in per day by the lungs, on average: 2,850.

* Number of diapers used per day at Childrens Hospital Los Angeles: 3,487.

* Approximate number of reference questions about health fielded per week by librarians at the Los Angeles Public Library, Central Library: 500.

* Number of books in print on diet and weight loss: 800.

* Heartbeats per day, on average: 100,800.

* Number of board-certified orthopedic surgeons in U.S.: 19,202. In California: 2,661.

* Number of visits to Venice Family Clinic, 1996: 70,692. Projected for ‘97: 75,000.

* Percentage of adult Americans who don’t meet the surgeon general’s guidelines for regular, moderate exercise: 60%.

* Number of Americans who die each year of sedentary lifestyle-related causes: 250,000.

* Number of extra calories, on average, needed daily after first trimester to maintain a healthy pregnancy: 300.

Sources: Kaiser Permanente, Los Angeles; Childrens Hospital Los Angeles; Billie Connor, Los Angeles Public Library, Central Library; Angela Barrett, R.R. Bowker, publisher of Books in Print; Prevention’s Giant Book of Health Facts (Rodale Press, 1991); American Academy of Orthopaedic Surgeons; American Board of Orthopaedic Surgery; Mary Richert, Venice Family Clinic; Meredith L. Yetman, International Health, Racquet & Sportsclub Assn.’s Research on Exercise Report, 1997; the American Dietetic Assn.’s “Complete Food and Nutrition Guide.”