Vitamin D2 in Milk: Does It Really Help Kids?

randomized-controlled-trial PMID: 34302325

Quick Summary: A study looked at whether giving kids milk fortified with Vitamin D2 could boost their Vitamin D levels. The results showed that while the fortified milk did slightly improve levels, it wasn't enough to fix the Vitamin D deficiency in these children.

What The Research Found

Researchers wanted to see if adding Vitamin D2 to milk would help children with low Vitamin D levels. They gave some kids milk with added Vitamin D2 and others plain milk for three months. The kids who drank the Vitamin D2 milk did have slightly better Vitamin D levels than those who drank plain milk. However, neither group reached healthy Vitamin D levels. The Vitamin D2 milk also seemed to help with some other health markers, but it wasn't a complete solution.

Study Details

Who was studied: 235 healthy children aged 10-14 years old in India who had low Vitamin D levels.

How long: The study lasted for 3 months, from October to December.

What they took: One group of kids drank 200 mL of milk daily that was fortified with 240 IU of Vitamin D2. The other group drank the same amount of plain milk.

What This Means For You

Vitamin D is important: Vitamin D is crucial for healthy bones and overall well-being.

Fortified milk might not be enough: If you live in an area with limited sunlight, or if you or your child has a Vitamin D deficiency, fortified milk alone might not be enough to get your levels where they need to be.

Talk to your doctor: If you're concerned about your or your child's Vitamin D levels, talk to your doctor. They can test your levels and recommend the best way to get enough Vitamin D, which might include supplements or a higher dose of Vitamin D.

Study Limitations

The dose might have been too low: The amount of Vitamin D2 added to the milk might not have been high enough to make a big difference.

Short study: The study only lasted for three months, so we don't know if the results would be the same over a longer period.

Location matters: The study was done in India during the winter. The results might be different in other places or at different times of the year.

Other factors not measured: The study didn't look at all the ways Vitamin D works in the body.

Bone health findings are unclear: The study's results on bone health were a bit confusing and need more research.

Key Findings

Daily supplementation of 200 mL milk fortified with 240 IU vitamin D2 (ergocalciferol) for 3 months did not correct vitamin D deficiency in Indian children aged 10–14 years during winter. While serum 25(OH)D levels were significantly higher in the intervention group compared to controls post-study (10.8 vs. 6.7 ng/mL, P<0.001), neither group achieved sufficient levels (>20 ng/mL). The intervention reduced secondary hyperparathyroidism (13.3% vs. 39% in controls, P<0.001) but increased bone formation markers (serum procollagen type 1 N-terminal propeptide) in the control group.

Study Design

This was a double-blind, randomized placebo-controlled trial conducted in Delhi, India, from October–December 2019. The study included 235 healthy children (10–14 years) with baseline vitamin D deficiency. Participants were randomized to receive either vitamin D2-fortified milk (n=119) or plain milk (n=116) daily for 3 months. Outcomes included serum 25(OH)D, parathyroid hormone (PTH), bone turnover markers, and urinary calcium/creatinine ratio (U-Ca/CrR).

Dosage & Administration

The intervention group consumed 200 mL of milk fortified with 240 IU (6 µg) of vitamin D2 (ergocalciferol) daily. The control group received 200 mL of unfortified milk. Supplementation occurred under supervised school settings to ensure adherence.

Results & Efficacy

Serum 25(OH)D: Baseline levels were similar (control: 11.9±3.8 ng/mL; intervention: 11.4±3.6 ng/mL, P=0.23). Post-intervention, levels declined in both groups but less so in the intervention group (10.8±3.4 vs. 6.7±3.5 ng/mL, P<0.001).
Secondary Hyperparathyroidism: 39% of controls developed elevated PTH (>65 pg/mL) versus 13.3% in the intervention group (P<0.001).
Bone Turnover Markers: Serum carboxy-terminal telopeptide (CTX, a resorption marker) remained unchanged between groups. However, procollagen type 1 N-terminal propeptide (P1NP, a formation marker) was higher in controls (P<0.007), suggesting impaired bone formation in the intervention group.
Safety: No significant differences in U-Ca/CrR, indicating no increased risk of hypercalciuria.

Limitations

Insufficient Dose: 240 IU/day of vitamin D2 may be inadequate to correct severe deficiency in winter months.
Short Duration: A 3-month intervention may not reflect long-term efficacy or safety.
Population Specificity: Results apply only to vitamin D-deficient children in northern India during winter; generalizability is limited.
No Active Form Measurement: Lack of data on 1,25-dihydroxyvitamin D levels restricts understanding of metabolic effects.
Bone Health Uncertainty: Conflicting bone marker results (elevated P1NP in controls) require further investigation.

Clinical Relevance

For children with vitamin D deficiency in regions with limited sunlight (e.g., winter in northern India), daily supplementation of 240 IU vitamin D2 via milk may not achieve therapeutic targets. Clinicians should consider higher doses or alternative forms (e.g., D3) for effective repletion. Public health programs fortifying milk with low-dose D2 may need reassessment to address seasonal deficiency risks.

Source: PubMed | Year: 2021 | Type: Randomized Controlled Trial

Vitamin D2 in Milk: Does It Really Help Kids?