The U.S. Department of Health, Education and Welfare will host its first health fair, called Health Works '79 from 10 a.m. to 5 p.m. Tuesday through Thursday at the Mall along Independence Avenue NW between 3rd and 4th Streets.

The fair will concentrate on simple techniques to prevent diseases.HEW hopes the fair will serve as a model for communities around the country, a spokesman said.

Exhibits and special events will illustrate ways to improve health through better nutrition, physical fitness, coping with stress and accident prevention, a spokesman said.

Fair highlights include a VIP run Tuesday morning after opening ceremonies, featuring District of Columbia Mayor Marion Barry, Redskins coach Jack Pardee and skiing champion Suzy Chaffee; a recreational two mile jog open to the public, which starts at the fairgrounds at 10 a.m., and a special exhibit called "a walk through a fat cell."

"The Fair will demonstrate tha a few simple changes in our lives can improve our health and may add measurably to our lifespan," said Joseph A. Califano Jr., HEW secretary. "And at a time when health care costs are rising at an alarming rate, health activities which emphasize prevention of disease and illness promise to reduce overall expenditures for health care."