From the ‘freshman 15’ to STDs, incoming college freshman have a lot to watch out for.

It’s a stark reality about the first year of college: while freshmen account for a quarter of college students, they make up a third of all campus deaths.

According to a study by the American Public Health Association, suicide is the leading cause of death among college students—a danger that can be the result of many factors, including the ones outlined here. However, alcohol-related death rates are lower than what most people believe. In fact, college students are much less likely to die than people of the same age who are not seeking higher education.

“While they’re still adults, research has shown that the brain is still developing, specifically the parts related to decision-making,” Dr. Tiffany Sizemore-Ruiz, a physician and owner of Choice Physicians of South Florida who specializes in internal and preventative medicine, told Healthline.

There are many other adverse health effects college students face in their first year away at school.

According to a study in the Journal of Nutritional Behavior, about 80 percent of freshman don’t fit regular exercise into their schedules. Combine that with the fact that many college students subsist on instant ramen noodles, there’s a reason that many pack on the “freshman 15” (or more).

There have even been some cases of college students developing scurvy—the pirate disease caused by a lack of vitamin C—but it is much less common than the lore suggests. Still, a 1998 a study at Arizona State University found that 10 percent of students had serious vitamin C deficiencies, showing that college diets aren’t ideal.

“Nutrition is very, very important. We know in adults in the late 20s or early 30s, they develop their eating habits in their early young adult life,” Sizemore-Ruiz said. “One you gain that freshman 15, it’s going to follow you as a senior and into adulthood.”

While binge drinking certainly isn’t good for you, the alcohol itself creates fewer problems than the actions it can fuel.

Joshua M. Lawrence, Ph.D., director of the Counseling Services Center at Husson University in Bangor, Maine, said binge drinking leaves college freshman vulnerable to being victimized.

“A big piece we always worry about nationally is the influence of alcohol and assaultive behavior. Binge drinking, especially with first-year students, is associated with serious critical events, such as overdose and assault,” he said.

Half of all accidental college deaths have been linked to drug or alcohol abuse, whether from falling off a balcony at a party or driving drunk. While no one is expecting college kids to be teetotalers, Sizemore-Ruiz says having a good group of friends can prevent many problems.

“That’s the problem with college kids. They’re making bad decisions in social circles,” she said. “If someone doesn’t have your best interests at heart, you need to dump them.”

The U.S. Centers for Disease Control reports that half of the 20 million new sexually transmitted disease cases each year occur in people ages 15 to 24. Many of the more common STDs are treatable, but some can have life-long effects.

Sizemore-Ruiz says STDs are a major concern because many can affect a woman’s fertility later in life.

Prescription drugs are becoming more and more popular, and college campuses are seeing an upswing in the use of prescription “performance-enhancing” drugs like Ritalin and Adderall to fuel late-night cram sessions.

“Some students may be using it as a great way to improve grades, while others may be using this to get high,” Lawrence said.

Besides the health effects, there are also legal consequences to possessing these drugs.

“Depending on the university environment, they may not know the legal ramifications of carrying a class-2 controlled substance,” he added.

Freshman face an overload of stress, which can create sleep problems, poor grades, and worse, according to Sizemore-Ruiz. And lack of quality nutrition and exercise compound the problem because they can weaken the body and make stress harder to bear.

“It kind of snowballs out of control,” she said. “Stress, nutrition, and exercise are all tied together 100 percent.”

As incoming freshmen break free from the structure of home, it can lead to anxiety, depression, and isolation. And these feelings can be dangerous.

“Stress is huge,” Lawrence said. “That lack of structure can be stressful because they don’t know what to do.”

“One of the messages we work on, and we can always do a better job at, is helping parents and their kids better prepare for the transition,” Lawrence said. “Having conversations with your kids about what you can expect, both as parents and students, would help us get ahead of the problems we’re experiencing.”

Sizemore-Ruiz had a decidedly atypical college experience: she graduated from college at 19 and medical school at 23. She says that without the support of her parents, she would never have been able to get through it.

“[Freshmen] still need their mommy and daddy for reinforcement, but they still want their independence,” she said. “As much as parents don’t want to have the conversation because it’s awkward, it needs to be had. It’s about understanding and being sincere. Sincerity goes a long way.”