Meeting Both Diet and Exercise Standards Significantly Lowers Hospitalization Risk
Many people assume that eating well is enough, but a new study from Seoul National University Hospital suggests otherwise: diet and exercise are both essential. Using data from the Korea National Health and Nutrition Examination Survey, the research team analyzed 37,059 adults aged 20 and over to assess the relationship between diet quality, physical activity, and health care use.
How Was the Study Conducted?
Diet quality was divided into high and low groups based on the median score of the Korean Healthy Eating Index (KHEI). For physical activity, leisure-time activities including walking were converted into moderate-intensity equivalents, and those logging 150 minutes or more per week were classified as active. Moderate intensity refers to activity that leaves a person slightly short of breath.
The team then combined the two criteria to sort participants into four groups:
- High diet quality + sufficient activity (both standards met)
- High diet quality only
- Sufficient activity only
- Neither standard met (reference group)
Key Finding: 1+1 > 2
The analysis found that the odds of hospitalization in the group meeting both standards were 11% lower than in the reference group (adjusted odds ratio 0.89). Notably:
- The group sufficient only in physical activity had a similar odds ratio of 0.90, but the result was not statistically significant;
- The group high only in diet quality came in at 1.02, little different from the reference group.
This suggests that a healthy diet or exercise alone does not clearly reduce hospitalization risk—only the combination shows a protective effect.
Who Benefits Most?
In stratified analyses by participant characteristics, the link between physical activity and hospitalization was clearer in some groups. Regardless of diet quality, the active groups showed the following reductions in hospitalization odds:
- Patients with chronic illness: 15%–18% lower
- Women: 18%–22% lower
- Adults aged 65 and over: 28%–30% lower
By contrast, no statistically significant link was found among men, adults under 65, and people without chronic illness.
Outpatient Visits Show an Opposite Trend
Interestingly, outpatient visits showed a different pattern from hospitalization: groups with a high-quality diet were in fact more likely to have received outpatient care. Compared with the reference group, the adjusted odds ratio for outpatient visits was 1.19 in the group high only in diet quality and 1.09 in the group meeting both standards.
The team suggested that people with a high-quality diet may pay more attention to their health in general and therefore seek medical care more actively. They also raised the possibility of reverse causation—that people in better health may be more able to maintain a healthy diet.
What This Means for You
The message is clear: a healthy diet and regular exercise should go hand in hand. For women, older adults, and people with chronic illness, sticking to 150 minutes of moderate-intensity exercise per week (such as brisk walking, cycling, or swimming) is especially worthwhile. You can use the "Xiaoshu Health App" to sync Apple Health data and track steps, exercise duration, and heart rate, helping you see whether you're meeting activity goals—and truly putting "eating well" and "moving enough" into practice every day.