Which vitamins help with PMOS symptoms?

Vitamin D, inositol and omega-3s have the strongest evidence base for PMOS. Zinc, vitamin E, and B12/folate (especially if taking metformin) are also worth discussing with a clinician. None are licensed treatments for PMOS.

Do supplements work for PMOS?

Some supplements show promising evidence for specific symptoms — particularly vitamin D for insulin resistance and inositol for cycle regularity — but none are licensed treatments for PMOS. Individual results vary, and supplements work best alongside medical care and lifestyle changes.

Does PMOS require different supplements than PCOS?

No. PMOS and PCOS are the same condition with a new name. All existing supplement evidence applies equally. Nothing about the rename changes the underlying biology or the research.

What is the best supplement for insulin resistance in PMOS?

Inositol (particularly myo-inositol) and vitamin D have the most evidence for supporting insulin sensitivity in PMOS. Always speak to a healthcare professional before starting supplements, as results vary and individual circumstances matter.

TribElle featured image with soft pink and lilac background. A confident woman stands on the right. Title text reads: “Vitamins and Supplements for PCOS: What Science Actually Says.” Decorative vitamin icons and molecular graphics appear in the corners, symbolising health and evidence-based science.

PCOS PMOS

Vitamins and Supplements for PMOS (formerly PCOS): What the Science Says

TribeTeam

September 7, 2025

Updated 21 May 2026

PCOS is now officially called PMOS

Following the May 2026 Lancet consensus, PCOS is now PMOS (polyendocrine metabolic ovarian syndrome). And if anything, that new name makes the case for these supplements even clearer. Read the Lancet paper →

Reviewed by Julie Boora, Superintendent Pharmacist, TribElle Health Ltd (GPhC Reg. 9012688) · Updated 21 May 2026

If you've ever searched for "PCOS/PMOS supplements," you've probably been buried under endless advice, miracle claims, and half-truths. At TribElle, we believe you deserve better: straight answers, backed by science, in plain English.

Here's what the research actually says about vitamins and supplements in PMOS — what helps, what doesn't, and how to take them so they actually work for you.

Vitamin D: the sunshine vitamin

PMOS is now formally recognised as a metabolic condition, and vitamin D's role in insulin resistance sits right at the heart of that. Many women with PMOS have low vitamin D — and that matters. Low levels have been linked to worse insulin resistance, higher testosterone, and irregular cycles.

The science

→	A review of 11 clinical trials found vitamin D supplementation improved insulin resistance and lowered testosterone in women with PCOS/PMOS. Nutrients, 2018

→	A larger 2025 review confirmed improvements in blood sugar and cholesterol — including lower fasting glucose, insulin, triglycerides, and LDL. BMC Endocrine Disorders, 2025

Best time to take it: With a meal that contains fat. Morning or midday is ideal — high doses at night can affect sleep.

Inositol: promising but not a silver bullet

The PMOS rename specifically highlights insulin signalling pathways as central to the condition — which is exactly why inositol has attracted so much research interest. Inositols (myo- and D-chiro) are natural compounds that help with insulin signalling. Many women with PMOS don't process them properly, which can fuel insulin resistance and irregular cycles.

The science

→	A Cochrane review (2019) of 13 trials found inositol may improve ovulation and reduce testosterone, but the quality of evidence was low to moderate and more large-scale studies are needed.

→	A 2024 systematic review by Monash University echoed this: results look promising, but the evidence base is still limited and inconsistent. JCEM, 2024

Best time to take it: Inositol is water-soluble, so timing with food doesn't matter. Splitting the dose (morning and evening) may help keep levels steady.

TribElle takeaway: Inositol shows promise for improving cycles and hormone balance in some women with PMOS, but it's not a one-size-fits-all solution. Individual results vary.

Omega-3s: good fats for hormones and metabolism

Omega-3 fatty acids (EPA and DHA from fish oil or algae) are well known for their benefits on heart and metabolic health. For women with PMOS, the focus is on whether they can improve insulin resistance and cholesterol balance.

Omega-3s may play a supportive role in addressing the inflammatory and metabolic dysfunction associated with PMOS, helping promote insulin sensitivity, hormonal balance, and long-term ovarian-metabolic health.

The science

→	A meta-analysis of randomised controlled trials found omega-3 supplementation improved insulin resistance, lowered cholesterol and triglycerides, and boosted adiponectin — a hormone that helps the body respond to insulin. Reproductive Biology and Endocrinology, 2018

Best time to take it: With your main meal (especially one containing fat) to maximise absorption. Evening doses may also help reduce "fish burps."

TribElle takeaway: Omega-3s show strong evidence for improving metabolic markers in PMOS. While more research is needed on hormone balance, they're a safe, supportive option many women find helpful.

Vitamin E: antioxidant support

Vitamin E is a strong antioxidant. For women with PMOS, oxidative stress plays a role in worsening hormone imbalances and insulin resistance.

The science

→	A 2020 trial found women taking vitamin E had lower LH and testosterone, higher progesterone, and healthier cholesterol levels. PubMed, 2020

Best time to take it: With food that contains fat. Works well when paired with vitamin C.

Vitamin B12 and folate: smart support when you're on metformin

Metformin is commonly used to manage PMOS, but one important thing to know is that it can lower vitamin B12 levels over time. That's why many clinicians recommend monitoring B12 if you're on long-term metformin.

The science

→	Women with PMOS on metformin are more likely to develop low B12 compared with those not taking it

→	Adding B-vitamins and folate can support healthy homocysteine levels — a marker linked to cardiovascular and metabolic health

→	Folate co-supplementation alongside metformin has been shown to support vascular health markers and improve metabolic balance. PubMed, 2010

Best way to take it: B12 in the morning, on an empty stomach or with a light meal. Folate any time of day — it's water-soluble and well absorbed.

TribElle takeaway: If you're on metformin, it's worth checking your B12 levels periodically and asking your clinician whether adding folate makes sense for you.

Zinc: small but mighty

Zinc helps with insulin sensitivity, skin health, and hair — three areas that matter a lot for women with PMOS.

The science

→	A comprehensive review found evidence that zinc supplementation may improve markers of insulin resistance and support healthier lipid profiles in women with PCOS/PMOS. Nutrients, 2020

Best time to take it: On an empty stomach if tolerated. If it upsets your stomach, take it with a small evening meal — avoid dairy or coffee at the same time.

The TribElle take

Supplements won't cure PMOS. But the right ones, taken in the right way, can ease symptoms, support hormones, and improve long-term health.

The best evidence is for:

✔

Vitamin D

✔

Omega-3s

✔	Vitamin B12 and folate (especially if on metformin)

Everyone's body is different. Supplements work best alongside medical care, nutrition, movement, and sleep.

Frequently asked questions

Important note

This blog is for general information only. Supplements are not licensed medicines for PMOS in the UK. Research is ongoing and results vary. Always speak to a healthcare professional before starting anything new.