Researchers compared vitamin D levels in over 8,400 people to see if back problems increase the risk of vitamin D deficiency. They found that while vitamin D deficiency is common (affecting about 2 out of 3 healthy people), people with degenerative disc disease in their lower back actually had similar or slightly better vitamin D levels than healthy controls. Age, sex, body weight, and season all affected vitamin D levels in both groups. The study suggests that back disease itself doesn’t cause vitamin D deficiency, though both conditions are common health concerns worth monitoring.

The Quick Take

  • What they studied: Whether people with degenerative disc disease (wear-and-tear damage in the lower spine) are more likely to have low vitamin D levels compared to healthy people
  • Who participated: 7,300 healthy people from routine health screenings and 1,147 people who had surgery for lower back disc problems. All participants had their blood vitamin D levels tested
  • Key finding: Surprisingly, people with back disease had slightly higher vitamin D levels than matched healthy controls. About 67% of healthy people had low vitamin D, but only 43% of back disease patients did. When researchers matched groups by age and other factors, the difference in deficiency rates disappeared
  • What it means for you: If you have back problems, low vitamin D is not necessarily caused by your back condition. However, vitamin D deficiency is very common in the general population, so it’s worth checking your levels regardless of whether you have back issues

The Research Details

This was a retrospective comparative study, meaning researchers looked back at medical records and test results that had already been collected. They compared two groups: people who came in for routine health screenings and people who needed surgery for lower back disc degeneration. All participants had their blood vitamin D levels measured using standard lab tests.

To make the comparison fair, researchers used a statistical technique called propensity score matching. This is like creating a “twin” healthy control group that matched the back disease patients in terms of age, sex, body weight, and other important factors. This helps ensure that any differences found were due to the back condition itself, not other differences between the groups.

The researchers analyzed how age, sex, body weight, and season affected vitamin D levels in both groups to understand what factors influence vitamin D deficiency.

This study design is important because it lets researchers compare real-world patients rather than doing an artificial experiment. By matching the groups carefully, they could isolate whether back disease itself causes low vitamin D or if other factors are responsible. Understanding this relationship helps doctors know whether treating back problems might improve vitamin D levels, or if vitamin D needs to be addressed separately.

Strengths: Large sample size (over 8,400 people) provides reliable results. All participants had actual blood tests rather than relying on symptoms. The matching process helped create fair comparisons. Limitations: This was a single-center study (one hospital), so results might differ in other locations. The study looked backward at existing data rather than following people forward over time. People who needed surgery for back problems might be different from those with mild back issues who didn’t need surgery.

What the Results Show

The most surprising finding was that people with degenerative disc disease actually had slightly higher median vitamin D levels (21.6 ng/mL) compared to matched healthy controls (19.3 ng/mL). This difference was statistically significant, meaning it wasn’t due to chance.

However, when researchers looked at the actual rates of vitamin D deficiency (defined as levels below 20 ng/mL), there was no significant difference between the back disease group and the matched healthy controls. This means that while the back disease group had somewhat higher average levels, they weren’t dramatically less likely to be deficient.

The study found that vitamin D deficiency was surprisingly common overall: about 67% of healthy screening participants had low vitamin D, while 43% of back disease patients did. This large difference between the two groups disappeared when researchers carefully matched them for age and other factors, suggesting that age and other characteristics—not the back disease itself—explained most of the difference.

Several factors influenced vitamin D levels in both groups: Age showed an unusual pattern—vitamin D levels increased in younger people but then decreased in older adults after reaching a peak. Women were more likely to have vitamin D deficiency than men. People with higher body weight had lower vitamin D levels. Winter and spring seasons were associated with lower vitamin D levels compared to other seasons, likely due to less sun exposure.

Previous research has shown that vitamin D levels correlate with outcomes in back disease patients, suggesting vitamin D might be important for spine health. However, this study is one of the first to directly compare whether back disease actually causes vitamin D deficiency. The findings suggest that the relationship between vitamin D and back disease may be more complex than a simple cause-and-effect—low vitamin D might not be caused by having back problems, but it could still affect how the condition progresses.

The study only included people from one medical center, so results might not apply everywhere. People who needed surgery for back problems represent a more severe group than all people with back issues. The study looked at data collected in the past rather than following people forward, so researchers couldn’t determine if vitamin D changes over time. The study couldn’t prove cause-and-effect relationships, only associations. Seasonal variation in vitamin D testing might have affected results if different groups were tested in different seasons.

The Bottom Line

Based on this research (moderate confidence): Get your vitamin D levels checked as part of routine health screening, regardless of whether you have back problems. If you’re deficient, work with your doctor on supplementation or increased sun exposure. Don’t assume that back disease is causing your low vitamin D—they appear to be separate issues. Pay special attention to vitamin D if you’re female, have a higher body weight, or live in a climate with limited winter sun.

Everyone should care about vitamin D levels since deficiency is very common. This study is particularly relevant for people with lower back disc problems who might wonder if their back condition is causing vitamin D deficiency (it probably isn’t). Women, older adults, and people with higher body weight should be especially vigilant about checking vitamin D levels. People living in northern climates or those with limited sun exposure should consider vitamin D screening.

Vitamin D deficiency doesn’t develop overnight. It typically builds up over months of inadequate sun exposure or dietary intake. If you start supplementing, it may take 4-8 weeks to see meaningful improvements in blood levels. Benefits for bone health and other functions may take several months to become apparent. Seasonal changes in vitamin D levels occur naturally, with levels typically dropping in winter months.

Want to Apply This Research?

  • Track your vitamin D supplementation (if prescribed) and note the date and result of your last vitamin D blood test. Set reminders for seasonal vitamin D testing (especially before winter) and record sun exposure time on days when you’re outdoors for 15+ minutes
  • If your vitamin D is low, use the app to set a daily reminder to take your vitamin D supplement at the same time each day. Log outdoor time during sunny days to help you maintain consistent sun exposure. If you have back problems, track both your back symptoms and vitamin D supplementation separately to see if they’re related for you personally
  • Schedule annual vitamin D blood tests and log results in the app to track trends over years. Monitor seasonal patterns by comparing your vitamin D levels from winter versus summer. If supplementing, retest after 8-12 weeks to confirm your levels are improving. Track any changes in back pain or other symptoms alongside vitamin D levels to identify personal patterns

This study suggests an association between vitamin D and back disease but does not prove that one causes the other. The findings are from a single medical center and may not apply universally. If you have back problems or suspect vitamin D deficiency, consult with your healthcare provider for personalized evaluation and treatment. Do not start, stop, or change any supplements or treatments based solely on this research. Vitamin D supplementation should be guided by blood tests and medical advice, as excessive vitamin D can be harmful. This information is for educational purposes and should not replace professional medical advice.