A 20-Year Study Just Showed How Your Habits In College Impact Your Health

College isn't exactly known as a time when people make their healthiest decisions. Many students stay up late socializing or cramming for exams, rely on convenience foods, and drink more than usual.

But it's also a time when many people continue healthy habits they grew up with or start new ones (like going to the gym regularly).

And those habits may matter more than we think. According to a new study, the lifestyle patterns people maintain during their college years can help shape their health for decades. Here's what you need to know.

About the study

Researchers at Tufts University tracked nearly 5,000 incoming undergraduate students between 1998 and 2007. Each student completed a health survey before starting college. Then, in 2018, 970 of those original participants completed a follow-up alumni survey, giving researchers a window into how their lifestyle behaviors and weight had changed over 11 to 20 years.

Using statistical modeling, researchers grouped participants into five lifestyle patterns based on behaviors like diet, physical activity, and other health-related habits:

They also examined how participants' body mass index (BMI) changed over the same period. It's important to note that BMI alone is not reflective of a person's individual health. However, it's still a common metric used in these large scale studies to show patterns and general trends (particularly about metabolic health) over time.

Weight gain is common after college (but not equal)

Across the group, weight gain became more common over time. During the follow-up period (roughly 11 to 20 years) the prevalence of overweight more than doubled, rising from 12% to 26%. Excess weight gain also increased, climbing from 2% to 8%.

But the likelihood of moving into a higher BMI category varied depending on their lifestyle.

Those who maintained a stable minimally healthy lifestyle were more than twice as likely to move into a higher BMI category from where they started in college (34.9%) compared with those who maintained a stable healthy lifestyle (15.9%).

This means that about 1 in 3 people with consistently poorer lifestyle habits experienced a meaningful increase in weight status, while the shift happened in closer to 1 in 6 people with healthier habits.

Why this life stage matters

The researchers point to "emerging adulthood" (ages 18 to 25) as a critical period for the development of excess weight gain. While navigating a newfound independence and major schedule changes, many people experience shifts in eating patterns, activity levels, and sleep patterns.

Previous research1 supports this, finding that college students often report declines in exercise and diet quality compared to high school and may still be developing skills—like planning and self-monitoring—that help people maintain healthy habits in a new environment.

This makes a strong case for colleges to invest in environments that support healthy living, like accessible fitness options, nutritious dining choices, and mental health resources. But even if your campus isn't there yet, the research suggests that building consistent habits now can pay off for years to come.

The takeaway

This study provides further evidence that the habits we develop early in life are so important, but it's always possible to make a positive shift. And what feels extra promising is that younger generations are increasingly invested in health and healthy aging, which could help shift these trends in a positive direction in the following decades.