Leptin Resistance, Vitamin D Deficiency, and Fibroids: The Missing Link No One’s Talking About

February 26, 2025

If you feel like your body is working against you, it might not be “just hormones”

You’re eating well. Maybe even exercising. You’ve tried cutting sugar, balancing your macros, or even intermittent fasting. Yet the weight won’t budge. Or maybe you feel like you’re hungry all the time, even after a full meal. Or you wake up exhausted, your energy levels crash mid-afternoon, and your body just feels… off.

And if you have fibroids? The symptoms are even more relentless: heavy bleeding, clotting, pelvic discomfort, bloating that makes you look five months pregnant by the end of the day.

What if I told you that a hormone no one talks about, leptin, is a missing piece of this puzzle? And what if I told you that vitamin D deficiency might be keeping your body stuck in an endless loop of inflammation, weight gain, and fibroid growth?

Let’s get into it.

(Sources provided at the end of the article).

Leptin: The Hormone That’s Supposed to Keep You Balanced (But Sometimes Fails)

Leptin is your body’s appetite and metabolism regulator. It’s made by fat cells and acts like a messenger, travelling to your hypothalamus (the control centre of your brain) to tell you, “Hey, we’ve got enough energy stored. You don’t need to eat any more.”

In a healthy system, this keeps your metabolism running efficiently. You feel full when you need to. Your body burns fat when it should. You don’t have wild cravings.

But here’s the problem.

In a state of leptin resistance, this system breaks down. The message doesn’t get through. Your brain doesn’t “hear” leptin’s signals, so it thinks you’re starving, even when your fat cells are screaming that they have enough stored energy. The result?

Increased hunger and cravings (especially for high-calorie, sugary foods)
Slowed metabolism (your body literally clings to fat to protect you)
Fatigue and brain fog
Increased fat storage, especially around the midsection

Now, how does vitamin D play into this?

Vitamin D & Leptin Resistance: The Connection No One’s Talking About

Most people know vitamin D as the “sunshine vitamin.” But vitamin D isn’t just a vitamin, it’s a pro-hormone (a necessary factor for hormone production), and it plays a direct role in how leptin functions.

Here’s what we know:

Vitamin D is needed for leptin gene expression. If you don’t have enough vitamin D, your fat cells don’t produce leptin effectively. That means poor appetite regulation and a sluggish metabolism.
Your hypothalamus is packed with vitamin D receptors. If these receptors don’t get enough vitamin D, they can’t process leptin signals properly.
Vitamin D reduces inflammation. Chronic inflammation disrupts leptin signalling, keeping your body in a stressed, dysregulated state.

So, if you’re deficient in vitamin D, you’re basically turning the volume down on leptin’s signals. Your body is trying to regulate itself, but the tools it needs just aren’t there.

Now, let’s talk about fibroids, because this is where things get even more interesting.

The Fibroid Connection: Why Leptin Resistance and Vitamin D Deficiency Are Major Players

If you have fibroids, chances are you’ve been told some version of “It’s just hormonal” or “It’s genetic”. But what’s often left out of the conversation is how leptin resistance and vitamin D deficiency contribute to fibroid growth.

Here’s what we know:

Women with fibroids are more likely to be vitamin D deficient.
- Vitamin D has been shown to slow the growth of fibroid cells in multiple studies.
- When vitamin D levels are low, fibroid cells grow unchecked.
Leptin promotes fibroid growth.
- High leptin levels are directly linked to larger fibroids and increased fibroid growth.
- Since leptin resistance causes leptin levels to rise, this creates the perfect storm for fibroid development.
Inflammation plays a huge role.
- Chronic inflammation fuels both leptin resistance and fibroid growth.
- Vitamin D reduces inflammation, but when levels are low, fibroid-promoting inflammation thrives.

What does this mean in real life? If you have leptin resistance and vitamin D deficiency, your body is literally feeding your fibroids.

So how do we fix it?

A Holistic Approach: Herbal Medicine, Nervous System Balance, and Tissue States

As a herbalist, I don’t believe in quick fixes or symptom suppression. I look at the whole system: how metabolic, nervous, and reproductive health interact. Below are some places I would first address for a client with this symptom pattern. The specific herbs I would choose would differ depending on each person's unique presentation.

1. Address Leptin Resistance with Herbs and Nervous System Support

Metabolic Support – Bitter herbs like Dandelion root, Burdock, and Artichoke leaf help improve insulin and leptin sensitivity.
Nervous System Balance – The HPA axis (hypothalamic-pituitary-adrenal) connection plays a major role in leptin function. Chronic stress increases cortisol, which blocks leptin’s function. Adaptogens like Ashwagandha and Holy Basil help bring balance.
Lymphatic Movement – Fibroids thrive in stagnation, so keeping fluids moving is key. Cleavers and Red Clover support the lymphatic system.

2. Optimise Vitamin D Naturally

Sun Exposure – The best way to get vitamin D is through the skin. Aim for 20 minutes of direct sunlight daily on exposed skin.
Whole-Food Sources – Fat-soluble vitamins need dietary fat for absorption. Sources like egg yolks, fatty fish, and liver are great for boosting vitamin D levels.
Magnesium & K2 for Absorption – Vitamin D doesn’t work in isolation. Magnesium (in dark leafy greens and pumpkin seeds) and Vitamin K2 (in natto, cheese, and egg yolks) help your body use vitamin D properly.

3. Reduce Inflammation & Support Hormonal Balance

Anti-Inflammatory Herbs – Turmeric and Ginger help lower systemic inflammation, improving leptin and hormone function.
Oestrogen Metabolism – Fibroids are oestrogen-sensitive, and supporting healthy oestrogen clearance is key. Dandelion and Milk Thistle help the liver detoxify excess oestrogen.
Pelvic Circulation – Fibroids thrive in stagnant conditions. Herbs like Yarrow and Ginger improve blood flow to and through the uterus.

Final Thoughts: Reclaiming Your Health Holistically

Leptin resistance, vitamin D deficiency, and fibroids aren’t isolated problems, they’re interconnected. If you’ve been struggling with unexplained hunger, stubborn weight gain, or fibroids that seem to have a life of their own, it’s time to take a deeper look at your metabolic and hormonal health.

This isn’t just about taking a supplement. It’s about getting to the root: supporting your body with sunlight, nutrient-dense food, herbs that bring balance, and a holistic approach that honours the wisdom of your body.

If this resonated with you, I’d love to hear your thoughts. Drop a comment, share your experience, and let’s keep the conversation going.

References

Madhu SV, Aslam M, Mishra BK, Gupta A, Jhamb R. (2022). 'Association of 25 (OH) Vitamin D and Leptin in Individuals with Insulin Resistance' Indian Journal of Endocrinology and Metabolism. 26(5):435-438.

Baird, D. D., Hill, M. C., Schectman, J. M., & Hollis, B. W. (2013). 'Vitamin d and the risk of uterine fibroids' Epidemiology (Cambridge, Mass.), 24(3), 447–453.

Gui, W., Dai, M., Zhong, Z., Zhu, S., Gong, G., Chen, M., Guo, J., Zhang, Y. (2022). 'The association between vitamin D and uterine fibroids: A mendelian randomization study' Frontiers in Genetics, Section Evolutionary and Population Genetics, 13.

Naini, A. E., Vahdat, S., Hedaiati, Z. P., Shahzeidi, S., Pezeshki, A. M., Nasri, H. (2016) 'The effect of vitamin D administration on serum leptin and adiponectin levels in end-stage renal disease patients on hemodialysis with vitamin D deficiency: A placebo-controlled double-blind clinical trial' Journal of Research in Medical Sciences, 21(1).

Hajhashemi, M., Ansari, M., Haghollahi, F., & Eslami, B. (2019). 'The effect of vitamin D supplementation on the size of uterine leiomyoma in women with vitamin D deficiency'. Caspian journal of internal medicine, 10(2), 125–131. https://doi.org/10.22088/cjim.10.2.125