Vitamin D and Uterine Fibroids (Episode 453)

Full Transcript: Episode 453

Lisa Hendrickson-Jack:

Welcome to the Fertility Friday Podcast, your source for information about the Fertility Awareness Method and all things fertility. I’m your host, Lisa Hendrickson-Jack. I’m the author of The Fifth Vital Sign and the Fertility Awareness Mastery Charting Workbook. I’m a certified fertility awareness educator and holistic reproductive health practitioner with over 20 years of experience teaching women to connect to their fifth vital sign through menstrual cycle charting, balancing hormone health, and optimizing the menstrual cycle without hormones.

I’ve been consistently outspoken about hormonal birth control over the past two decades and its impact on fertility and overall health because you have the right to know how your body works and how artificial hormones disrupt that natural process. I teach women’s health professionals how to utilize the menstrual cycle as a vital sign in their practices, and I host live coaching programs to help you achieve optimal fertility and health because it’s important to have healthy menstrual cycles regardless of whether or not you want to have babies.

I’m also a wife and mother of two beautiful boys and a brand new baby girl. This podcast is designed to empower you to take full control of your cycles, your fertility, and your overall health. I’m so excited that you’re here with me today.

Today I’m sharing a brand new episode in my FAM Research Series. Today’s topic is vitamin D and fibroids. I thought it would be a good follow-up to last week’s episode about fibroids, so let’s go ahead and jump right in.

As I mentioned, the topic of today’s episode is vitamin D and fibroids. In case you missed the first episode in the FAM Research Series, this is a new series I’m starting this year where I go through interesting research papers, review the findings, and discuss what they may mean in terms of fertility awareness charting and hormone health. That will essentially be the format of these FAM Research Series episodes.

Today we’re going through a study titled Effect of Oral Consumption of Vitamin D on Uterine Fibroids: A Randomized Clinical Trial.

Before getting into the study itself, I want to do a quick review of uterine fibroids to give us a starting point. Uterine fibroids, also known as myomas or leiomyomas, are benign tumors of the smooth muscle cells found in the uterus. What we know about fibroids is that estrogens and progestogens proliferate tumor growth.

If fibroids are going to grow at any point in life, it’s typically during the reproductive years, and they tend to regress somewhat after menopause.

Fibroids are the most common benign tumors in women and are the leading cause of hysterectomies in the United States. They’re extremely common, with prevalence estimates ranging from 20 to 40 percent among women of reproductive age.

Fibroids are more common in African American women. In several research studies, rates of fibroids in Black women by age 35 were as high as 60 percent, increasing to over 80 percent by age 50. In contrast, white women showed rates of about 40 percent by age 35 and nearly 70 percent by age 50. Fibroids are common in all women, but they do appear at higher rates in Black women.

Fibroids can be asymptomatic, meaning someone can have them without knowing. They can also be associated with a number of symptoms. Some of the most common include abnormal uterine bleeding, heavy and prolonged menstrual bleeding, and pain, depending on location. Fertility-related effects also depend on size and location.

I also want to share that I have experienced fibroids myself. In my case, they’ve remained fairly stable over the years. On an anecdotal level, I attribute that to a combination of reducing xenoestrogen exposure and supporting healthy cycles so I’m not exposed to excess estrogen. My experience highlights how much fibroid experiences can vary from woman to woman.

Now let’s get into the study itself. This was a placebo-controlled trial with two groups: one receiving vitamin D and the other receiving a placebo. Participants were women with fibroids who were also more likely to have lower vitamin D levels. Women who had recently taken vitamin D supplements were excluded, and vitamin D levels were tested at baseline.

The intervention involved administering 50,000 IU of vitamin D once per week over a 12-week period. Fibroid size was measured at the beginning and end of the study.

The results were interesting. Vitamin D supplementation did not significantly reduce fibroid size overall. However, in the control group, fibroids continued to grow, while in the vitamin D group, fibroid growth was largely stabilized. Some women experienced small, non-statistically significant reductions in fibroid size, but the main finding was prevention of further growth.

This suggests a correlation between vitamin D levels and fibroid growth. Correlation does not equal causation, and this study does not establish that low vitamin D causes fibroids. What it does suggest is an association worth further investigation.

There is broader research showing that women with fibroids tend to have lower vitamin D levels compared to women without fibroids. Vitamin D is also connected to overall fertility, hormone production, follicular development, and ovulatory health. Low vitamin D levels have been associated with hormonal imbalances and conditions such as PCOS.

It’s also important to consider population-level factors. Darker-skinned individuals require more sun exposure to produce the same amount of vitamin D as lighter-skinned individuals. Living in colder climates with less sun exposure may further increase the likelihood of vitamin D deficiency. This raises important questions about how environmental and biological factors may intersect with fibroid prevalence.

Studies like this highlight how much there is still to learn. Research often takes decades to translate into everyday clinical practice, and fibroids remain an area where many questions are unanswered.

I’m going to stop the episode here. This has been an interesting discussion about this particular study and the potential role of vitamin D in fibroid growth. If you found this episode helpful, I encourage you to share it. You can find the show notes and study links at fertilityfriday.com/453.

As always, thank you for listening. Until next time, be well and happy charting.