Vitamin D Pills for Vaginal Dryness: Two Trials, Different Findings

The earlier trial found no advantage over placebo

A 2020 trial¹ randomized 80 postmenopausal women with vaginal symptoms to 40,000 IU of vitamin D2 weekly or matching placebo for 12 weeks. Sixty-eight completed follow-up.¹

Vitamin D increased blood levels of the vitamin. It did not significantly outperform placebo on vaginal pH, vaginal-cell maturation or symptoms. At week 12, mean symptom severity was 2.94 out of ten in both groups.¹

Symptoms improved from baseline in both groups. Describing only the vitamin group’s improvement would omit the comparison needed to judge whether the supplement helped.¹

The later trial reported benefits, with reasons for caution

A 2025 trial² randomized 48 women to 60,000 IU of vitamin D2 weekly or placebo; both groups received calcium carbonate. Forty-one completed 12 weeks. Cell maturation, pH and symptom ratings favored vitamin D.²

But the cell-maturation scores already differed substantially before treatment:²

Group	Before / week 12
Vitamin D	43.6 / 47.8
Placebo	27.8 / 27.4

These are vaginal-cell scores, not percentages of women relieved of dryness. Much of the final difference existed before treatment, complicating interpretation.²

The methods describe a zero-to-ten symptom scale, yet the vitamin group’s baseline mean is 10.7. This unexplained discrepancy makes the reported relief difficult to interpret.²

The studies did not randomize women between the two doses. Their different findings do not establish that raising the dose improves vaginal symptoms.¹²

The trial doses need medical supervision

The NIH³ adult upper intake limit is 4,000 IU daily, including food, drinks and supplements. A clinician may prescribe higher doses temporarily to treat deficiency. That is a separate decision from taking extra vitamin D for dryness.³

Excessive supplementation can raise blood calcium and cause kidney stones or more serious harm. Vitamin D can also interact with medicines, including thiazide diuretics. Bring your supplement bottles and medication list to a pharmacist or prescriber before adding or increasing a dose.³

Give persistent dryness its own treatment discussion

NHS⁴ advice includes water-based lubricants for sex and vaginal moisturizers for dryness. See a GP if symptoms persist despite several weeks of self-care, affect daily life, or come with unusual discharge. Bleeding after sex or after menopause also needs assessment. Hormonal treatment may be an option after discussing suitability.⁴

If vitamin D has been prescribed for another reason, ask what it is treating, how long to take it, and how your vaginal symptoms will be addressed separately.

The “It Has a Name Now” section of Down There, Decoded explains how dryness, sexual discomfort and urinary symptoms can fit under genitourinary syndrome of menopause. Our moisturizer-versus-lubricant guide compares those product categories.