While shuffling the pages of her chemistry book, pre-nursing student Jennifer Cosker, 36, glances up with a look of exhaustion sweeping her face. She got less than five hours of sleep the night before, common since the semester began, and she is starting to feel a crash coming on.

"I'm just so tired," she said. "Sometimes it's so hard to keep up with it all."

Cosker said her school schedule plays a major role in her inconsistent eating and sleep patterns, but SF State students plagued with lethargy, poor concentration, sugar cravings or weight gain may need one thing more than a steady schedule, they may need a nutritional tune-up.

The Peers' Nutrition Assessment Clinic in the Student Health Center was estabilished to help students by providing an effective peer network for healthy living. PNAC offers students a customized diet analysis complete with waist-to-hip ratio, body mass index testing and blood pressure and diabetes screening.

"Irregular eating patterns, demands of work and a limited income can all impact your health," said registered dietitian and nutritionist Teresa Leu. "And eating poorly, choosing convenience foods packed with excessive fats and sugar, can have immediate effects on the body resulting in low energy."

While some students already know what they should and shouldn't eat, Leu, who oversees the PNAC program, emphasizes that "peers at PNAC assist students with meal plans that help support them during times of stress and keep their immune systems healthy."

With the PNAC seeing about 250 students each semester, Leu said she sees students who often go six or more hours without eating, then consume more than their daily calorie allowance in one meal.

Dietary habits like this could partly explain the findings of a nation-wide study based on 51 million young adults published in 2008 by the Centers for Disease Control and Prevention. The CDC's Web site reports that obesity in young adults, ages 18-29, "has more than tripled from 8 percent in 1971-1974 to 24 percent in 2005-2006." That means almost a quarter of young adults in this country are obese.

Sipping on coffee before class, sociology major Jonny Ceron, 25, junior, said he eats sporadically, skipping meals often and resorting to french toast sticks at Burger King for breakfast because he was in a rush to get to school.

"If I had the time, I'd probably eat better," Ceron said.

Students visiting PNAC will first fill out a nutrition intake form that includes everything they ate and drank in the previous 24 hours. A trained health student will then assess what dietary modifications the student needs, based on their goals, to achieve optimum health.

Students working in PNAC commit to a full year and are part of the Peer Educators Advocating Campus Health program. Generally PEACH students come from the nursing or health majors. As part of this year-long commitment, students must be trained for one semester by Leu or other Student Health Clinic staff members before working in the clinic.

Since the opening of PNAC in 2006, Leu said they have helped many students obtain their fitness and dietary goals. She recalls an athlete coming into the clinic wanting to learn how to build lean body mass. The student was consuming large quantities of protein while limiting his carbohydrates. A peer educator advised the student on the correct ratio of carbs and protein he needed to improve his endurance while increasing his muscle mass.

Out of 15 students interviewed for this article, 14 said convenience, money and time were all factors in their food choices as well as availability. From a sampling of restaurants surveyed in the Cesar Chavez Student Center, all carried some healthy choice options such as salads, wraps, yogurt and fruits.

Although there are healthy food options available on campus, for students like art major Jason Delgadillo, 21, senior, sometimes a banana or apple just doesn't hit the spot.

"I go for taste and pleasure," said Delgadillo, as he pumps ketchup on his plate of fries that accompanies his bacon cheeseburger. "I'll probably have beer for dinner. Beer's always the best dinner. That's usually how I roll."

PNAC will open Sept. 22 and be available to students every Tuesday and Wednesday from 1- 4 p.m.