For healthcare providers

Clinical guidance for recommending Sunlatched.

A resource for OBs, midwives, lactation consultants, and pediatricians supporting breastfeeding patients who want to optimize vitamin D for themselves and their infants.

Why this matters for your patients

Vitamin D deficiency in breastfed infants is a well-documented clinical challenge. Standard guidance recommends 400 IU/day supplementation for breastfed infants, but adherence to infant drops is often poor. Sunlatched offers an evidence-based alternative: maternal supplementation at 6,400 IU/day, studied to enrich breast milk to levels sufficient for infant needs.

Evidence overview

Clinical evidence summary

Landmark RCT support

Hollis et al. (Pediatrics, 2015) demonstrated that maternal supplementation with 6,400 IU/day produced breast milk vitamin D levels equivalent in infant outcome to direct infant supplementation of 400 IU/day.

Dose rationale

The 6,400 IU dose was selected based on the threshold required to reliably elevate breast milk 25(OH)D to levels sufficient for infant needs. Lower doses (400–2,000 IU) have not been shown to achieve this consistently.

Safety profile

6,400 IU/day is within the range studied in lactating women without adverse effects. The NIH tolerable upper intake level for adults is 4,000 IU/day; higher doses in supervised clinical contexts have a well-characterized safety record.

Monitoring recommendations

We recommend baseline and follow-up serum 25(OH)D testing for patients using Sunlatched. Target maternal 25(OH)D: 40–80 ng/mL. Adjust dosing as clinically indicated.

Read the full science page →

Patient selection

Appropriate patient profile

Exclusively or predominantly breastfeeding mothers

Patients with poor adherence to infant vitamin D drop regimens

Mothers with documented or suspected vitamin D insufficiency

Patients seeking to simplify their postpartum supplement routine

Mothers in low-sunlight climates or with limited sun exposure

Patients with darker skin tones at higher risk of vitamin D deficiency

Downloads

Provider resources

Clinical Evidence Summary (PDF)

A one-page summary of the key studies supporting 6,400 IU maternal supplementation, formatted for quick reference.

Patient Handout

A plain-language explainer for patients — how Sunlatched works, what to expect, and when to contact their provider.

Download PDF

Dosing & Monitoring Guide

Recommended baseline labs, target serum levels, follow-up intervals, and guidance for adjusting or discontinuing supplementation.

Provider inquiries

Get in touch

Questions about the clinical evidence, patient suitability, or bulk ordering for your practice? We'd love to hear from you.