When older adults break their hip, they often have very low vitamin D levels, which can slow their healing. Researchers tested two different ways of giving vitamin D supplements to 50 people over age 75 who had hip fracture surgery. Both methods worked well at raising vitamin D levels in the blood within one month. About half of the patients showed meaningful improvement in their ability to move and function after surgery. The study suggests that getting enough vitamin D after a hip fracture is important for recovery, though both daily and weekly supplement schedules worked equally well.

The Quick Take

  • What they studied: Whether two different vitamin D supplement schedules (daily versus weekly) could help older adults recover better after hip fracture surgery by raising their vitamin D levels
  • Who participated: 50 people aged 75 and older (average age 86) who had hip fracture surgery and low vitamin D levels. About two-thirds were women
  • Key finding: Both daily and weekly vitamin D supplements successfully raised vitamin D levels from very low (around 12-13) to healthy levels (around 35-38) within one month. About half of patients showed meaningful improvement in their ability to walk and do daily activities
  • What it means for you: If you’re an older adult recovering from hip fracture surgery, vitamin D supplementation appears to help your body heal better. Both daily and weekly supplement schedules work similarly, so you can choose whichever fits your routine better. Talk to your doctor about whether vitamin D supplements are right for you

The Research Details

This was a randomized controlled trial, which is one of the strongest types of medical studies. Researchers divided 50 older adults with hip fractures into two groups. One group received vitamin D supplements daily, while the other group received larger doses once per week. Both groups were carefully matched so they were similar at the start. The researchers measured vitamin D levels in the blood, checked a hormone called PTH (which responds to vitamin D), and tracked how well patients could walk and do everyday activities at discharge from the hospital and then at 3, 6, and 12 months after the fracture.

The study was designed to see if one supplement schedule worked better than the other for helping people recover. Researchers followed patients for a full year to understand both short-term and long-term effects. This long follow-up period is important because hip fracture recovery takes many months.

Hip fractures are serious injuries in older adults that can lead to long-term disability if recovery doesn’t go well. Vitamin D is crucial for bone health and muscle strength, both of which are essential for recovery. Many older adults already have low vitamin D levels, which makes recovery even harder. By testing whether vitamin D supplements help, this study provides practical guidance for doctors treating hip fracture patients. Understanding which supplement schedule works best also helps patients stick with their treatment

This study has several strengths: it was a randomized controlled trial (the gold standard for testing treatments), patients were followed for a full year, and researchers measured multiple important outcomes including blood vitamin D levels, hormone levels, and physical function. The study size of 50 patients is relatively small, which means results should be confirmed in larger studies. The study was registered before it started (NCT03213886), which is a sign of good research practices. However, the study doesn’t clearly explain how many patients completed all follow-up visits, which could affect the reliability of long-term results

What the Results Show

Both groups started with dangerously low vitamin D levels (around 12-13 ng/mL, when healthy levels are above 30). After one month of supplements, both groups reached similar healthy levels (around 35-38 ng/mL). This improvement happened whether patients took daily or weekly doses, showing both schedules work equally well.

About half of all patients showed clinically meaningful improvement in their ability to function—meaning they could walk better, do more daily activities, and had better overall mobility. This improvement was seen at hospital discharge and continued through the follow-up period.

The group receiving daily supplements showed a slightly better response in PTH hormone levels (which regulate calcium and vitamin D in the body), with PTH dropping more significantly compared to the weekly group. However, this difference didn’t translate into better long-term functional outcomes between the two groups.

Patients who didn’t reach optimal vitamin D levels showed less functional improvement overall, suggesting that actually achieving healthy vitamin D levels—not just taking supplements—is what matters for recovery

The study found that vitamin D supplementation was well-tolerated with no serious safety concerns reported in either group. Patients who achieved optimal vitamin D levels (above 30 ng/mL) had better functional outcomes than those who remained deficient, even within the treatment groups. The benefits of vitamin D supplementation appeared consistent across the 12-month follow-up period, suggesting sustained improvement rather than temporary gains

Previous research has shown that vitamin D deficiency is very common in older adults with hip fractures and is associated with worse outcomes. This study confirms that treating vitamin D deficiency is beneficial. The finding that both daily and weekly schedules work equally well is practical and aligns with other vitamin D research showing that total weekly dose matters more than the frequency of dosing. The study adds to growing evidence that vitamin D supplementation should be part of standard care for older adults recovering from hip fractures

The study included only 50 patients, which is a relatively small number. Results from larger studies would be more convincing. The study doesn’t clearly report how many patients completed all 12 months of follow-up, which could affect the reliability of long-term findings. The study doesn’t compare vitamin D supplementation to no treatment, so we can’t say for certain that the improvements were due to the supplements rather than other aspects of care. The study focused only on older adults (75+), so results may not apply to younger people with hip fractures. The study doesn’t provide detailed information about other factors that might affect recovery, such as physical therapy intensity or nutrition

The Bottom Line

If you’re an older adult recovering from hip fracture surgery, ask your doctor about vitamin D supplementation. The evidence suggests it may help your recovery. Both daily and weekly supplement schedules appear to work equally well, so choose whichever fits your routine better. Make sure your doctor monitors your vitamin D levels to confirm you’re reaching healthy levels. Vitamin D supplementation should be part of a complete recovery plan that includes physical therapy, adequate nutrition, and medical follow-up. Confidence level: Moderate (based on a small study that should be confirmed with larger research)

This research is most relevant for older adults (especially those 75+) who have had hip fracture surgery and have low vitamin D levels. It’s also important for doctors and physical therapists treating hip fracture patients. Family members helping with recovery should understand that vitamin D supplementation is a simple, safe addition to recovery care. People with other types of fractures or younger people with hip fractures should talk to their doctor, as this study specifically looked at older adults. People with kidney disease or certain other medical conditions should consult their doctor before starting vitamin D supplements

Vitamin D levels improved within one month of starting supplements. Functional improvements (ability to walk and do daily activities) were noticeable at hospital discharge and continued improving over the following months. Most meaningful recovery happens in the first 3-6 months, though improvements can continue for up to a year. Don’t expect overnight changes—recovery from hip fracture is a gradual process that takes months

Want to Apply This Research?

  • Track daily vitamin D supplement intake (daily or weekly dose) and record functional milestones such as: able to walk with walker, able to climb stairs, able to bathe independently, able to do light household tasks. Rate mobility on a simple 1-10 scale weekly
  • Set a daily or weekly reminder for vitamin D supplements based on your prescribed schedule. Log your supplement intake immediately after taking it. After each physical therapy session or doctor visit, update your functional ability notes in the app to see your progress over time
  • Create a monthly summary view showing supplement adherence percentage and functional improvement trends. Share this data with your doctor at follow-up appointments. Track any symptoms like muscle weakness or pain alongside your supplement intake to identify patterns. Set a goal to reach and maintain healthy vitamin D levels (above 30 ng/mL) as confirmed by blood tests

This research summary is for educational purposes only and should not replace professional medical advice. The study involved specific patients (those 75+ with hip fractures and low vitamin D) and results may not apply to everyone. Before starting any vitamin D supplements, especially if you have kidney disease, heart conditions, or take other medications, consult with your doctor or healthcare provider. Your doctor can determine the right dose for you and monitor your vitamin D levels with blood tests. This summary describes one study; treatment decisions should be based on your complete medical history and your doctor’s recommendations