Choosing the right Vitamin D for Fibroids

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Should I be taking Vitamin D for Fibroids?

Research has found a correlation between vitamin D deficiency and Fibroids. Some studies, while not definitive, also suggest taking a vitamin D supplement can prevent or slow the growth of fibroids. But which Vitamin D should you be taking?

What the science says

Vitamin D is one of the most researched nutrients linked to fibroid risk and progression. While it is not a cure, clinical studies suggest it may play a supportive role, particularly for women who are deficient.

Research into vitamin D and fibroids is promising but still emerging. Peer reviewed statically significant studies have proven a link between Vitamin D deficiency and Fibroids. However, only a handful of studies with small cohorts (100 participants or less) have show that taking Vitamin D supplements can slow or stop Fibroid growth.

There is no clinically founded evidence to support any claims that taking Vitamin D can shrink Fibroids.

What vitamin D can and can’t do

Evidence suggests it may support

✔️ Slowing or preventing fibroid growth in some women

✔️ Supporting normal hormone signalling

✔️ Addressing a common nutritional deficiency (especially in the UK)

What it does not reliably do

❌ Consistently shrink large fibroids

❌ Replace medical or surgical treatment

❌ Guarantee symptom improvement (e.g. bleeding or pain)

Vitamin D should be viewed as foundational, long-term nutritional support, not a standalone treatment.

The right type of Vitamin D for Fibroids

Vitamin D helps your body use calcium, magnesium, and phosphate. It is also classified as a hormone due to its effects on the reproductive system.

Vitamin D is involved in regulating cell growth, inflammation, and hormone signalling — all processes implicated in fibroids.

If you’re looking for Vitamin D supplements, it’s important you buy the correct type.

Types of Vitamin D

Vitamin D1 (calciferol) is found in fish oils.
Vitamin D2 (ergocalciferol) is found in plants.
Vitamin D3 (cholecalciferol) is produced by the body when UV light from the sun interacts with cholesterol in the skin.

The most active form of vitamin D is called 25-hydroxyvitamin D3. It has activity in almost every tissue of our bodies.

Vitamin D3 (cholecalciferol) is the form used in most fibroid-related studies and is more effective than vitamin D2 at raising and maintaining blood vitamin D levels.

What to avoid

Vitamin D1 (calciferol) or D2 (ergocalciferol)
Very low-dose supplements (e.g. 400 IU only)

What dosage should I look for?

Please consult your GP and request blood tests before making any changes to your diet.

Research commonly uses doses in the range of 2,000–4,000 IU (100 μg) per day, particularly where deficiency is present. If your doctor has recommended you take a different amount of vitamin D, you should follow their advice.

Higher doses are typically used to correct deficiency and should be tailored to individual needs. Do not take more than 100 micrograms (4,000 IU) of vitamin D a day, as it could be harmful. This applies to all adults (including pregnant and breastfeeding women) and children aged 11 to 17 years.

Vitamin D is best absorbed when taken with food containing fat. Some people also take vitamin D alongside magnesium and vitamin K2, which support vitamin D metabolism and calcium balance, though these have not been studied specifically for fibroid outcomes.

When should I take it?

There isn’t much in the way of studies in regards to time of day, but taking vitamin D with a meal, ideally rich in fats will increase absorption.

Medical Disclaimer - The information provided is intended to inform and educate women with Fibroids only, it is not a substitute for the professional judgment of a healthcare professional in diagnosing and treating Fibroids.

Warning - Taking too many vitamin D supplements over a long period of time can cause too much calcium to build up in the body (hypercalcaemia). This can weaken the bones and damage the kidneys and the heart. NHS

Consult your GP and request blood tests before making any changes to your diet.