Researchers studied 935 young adults to understand how their natural sleep patterns and exercise habits influence what they eat and drink. They found that people who exercise regularly drink more water and healthy beverages like tea and milk compared to those who are sedentary. Interestingly, people who are naturally “night owls” tend to eat less red meat and fish than “morning people.” The study suggests that when you sleep and how active you are play important roles in your nutrition choices, and doctors might want to consider these factors when giving dietary advice to young adults.

The Quick Take

  • What they studied: Whether the time of day you naturally wake up and how much you exercise affects what you eat and drink
  • Who participated: 935 healthy young adults between ages 18-30, with about two-thirds being female. Researchers divided them into three groups based on whether they were naturally morning people, evening people, or somewhere in between
  • Key finding: People who exercise regularly drink significantly more water and beverages like tea and milk than people who don’t exercise. Night owls tend to eat less red meat and fish than morning people
  • What it means for you: Your natural sleep schedule and activity level may influence your eating and drinking habits. If you’re a night owl or sedentary, you might want to pay extra attention to staying hydrated and eating enough protein. This is one study, so talk to a doctor before making major dietary changes

The Research Details

This was a cross-sectional study, which means researchers collected information from 935 young adults at one point in time rather than following them over months or years. Participants completed a questionnaire to determine their chronotype—basically, whether they’re naturally morning people, evening people, or in between. They reported how much exercise they did, and researchers asked them about everything they ate and drank using food recall surveys and questionnaires. The study was conducted in June and July to avoid seasonal changes that might affect eating habits.

The researchers used statistical analysis to look for patterns between sleep schedules, exercise levels, and dietary choices. They measured how strong these connections were and whether they were likely due to chance or real relationships.

Understanding how our biological rhythms and activity levels influence nutrition is important because it could help doctors and nutritionists give better, more personalized advice. Instead of one-size-fits-all dietary recommendations, healthcare providers could tailor suggestions based on whether someone is naturally a morning or evening person and how active they are

This study has a reasonably large sample size of 935 participants, which is good. However, because it’s cross-sectional, it shows associations but can’t prove that one thing causes another. The data was self-reported, meaning people had to remember and accurately report what they ate and drank, which can be imperfect. The study was conducted during summer months only, so results might not apply year-round

What the Results Show

People who reported being physically active drank significantly more water daily than sedentary people. Active individuals also consumed more black tea, herbal tea, iced tea, Turkish coffee, and milk. These differences were statistically significant, meaning they’re unlikely to be due to chance.

When looking at chronotype, morning people and intermediate types showed healthier beverage patterns overall. Evening types (night owls) drank less of these healthy beverages. Additionally, evening types consumed less red meat and fish compared to morning types. The reduction in fish consumption was particularly notable.

Interestingly, the differences in egg consumption between chronotypes were not statistically significant, suggesting that sleep schedule may not strongly influence how much egg people eat.

The study found that physical activity level had a stronger association with healthy drinking habits than chronotype did. The combination of being active and being a morning person appeared to create the healthiest beverage intake patterns. Evening types showed a consistent pattern of lower protein intake from animal sources, which could have nutritional implications if not compensated with other protein sources

This research builds on earlier studies showing that our internal body clocks influence eating and drinking. Previous research suggested that evening types might have different metabolic patterns, and this study provides evidence that their actual food and beverage choices differ too. The strong connection between physical activity and water intake aligns with what health experts already recommend—that active people need more fluids

The study relied on people’s memories of what they ate and drank, which can be inaccurate. All data was collected during summer months, so seasonal variations weren’t captured. The study shows associations but cannot prove that chronotype or activity causes dietary differences—other factors could be involved. The sample was 66.6% female, so results might not apply equally to men. Additionally, the study only included healthy young adults, so findings may not apply to older people or those with health conditions

The Bottom Line

If you’re sedentary, consider increasing water and tea intake as you become more active. If you’re a night owl, be intentional about including fish, red meat, or other protein sources in your diet to ensure adequate nutrition. These suggestions are based on observed patterns, not definitive proof, so individual needs vary. Consult a healthcare provider or registered dietitian for personalized advice

Young adults interested in optimizing their nutrition based on their natural sleep patterns and activity levels should pay attention to these findings. People who are evening types or sedentary may especially benefit from reviewing their beverage and protein intake. This research is less relevant for people outside the 18-30 age range or those with specific medical conditions requiring dietary restrictions

Changes in hydration and eating patterns can be noticed within days to weeks if you’re intentional about them. However, long-term health benefits from improved nutrition typically take several weeks to months to become apparent

Want to Apply This Research?

  • Log your daily water intake and tea/coffee consumption, noting your chronotype (morning, intermediate, or evening person) and whether you exercised that day. Track for 2-4 weeks to identify patterns in your own habits
  • Set a daily water intake goal based on your activity level (more water on active days), and if you’re an evening type, add a reminder to include protein-rich foods like fish or lean meat at meals
  • Weekly review of beverage intake trends correlated with activity level and sleep schedule. Monitor energy levels and digestion to see if adjustments based on your chronotype improve how you feel

This research shows associations between sleep schedules, activity levels, and eating habits in young adults, but does not prove cause-and-effect relationships. Individual nutritional needs vary based on age, health status, medications, and other factors. Before making significant changes to your diet or exercise routine, consult with a healthcare provider or registered dietitian, especially if you have any medical conditions or take medications that affect nutrition. This information is educational and should not replace professional medical advice.