Free UK delivery for orders over £50
365 Day Returns
£20 off orders over £100 – code MAY20
Free UK delivery for orders over £50
365 Day Returns
£20 off orders over £100 – code MAY20
Free UK delivery for orders over £50
365 Day Returns
£20 off orders over £100 – code MAY20
Free UK delivery for orders over £50
365 Day Returns
£20 off orders over £100 – code MAY20
Free UK delivery for orders over £50
365 Day Returns
£20 off orders over £100 – code MAY20
Free UK delivery for orders over £50
365 Day Returns
£20 off orders over £100 – code MAY20
Free UK delivery for orders over £50
365 Day Returns
£20 off orders over £100 – code MAY20

Undecylenic Acid

Your fatty acid support for a healthy balance of gut and vaginal flora.

Size:

250 caps

£31.04
Free sample each month
Pause or cancel anytime
365 day free returns
In stock. Next day delivery available.

Buy now, pay later from £8.62/mo with

Free UK shipping over £50, free returns.
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Key Benefits

  • Optimises gastrointestinal function for better digestion.

  • Essential for nutrient absorption and immune support.

  • Promotes a healthy balance of vaginal flora in women.

Thorne’s Undecylenic Acid is crucial for maintaining a healthy balance of gut flora, a key component of overall wellbeing. A balanced gut flora is vital for nutrient absorption, waste elimination, and robust immune function. Supplementing with Undecylenic Acid helps restore equilibrium among the microorganisms in the gastrointestinal tract, which can become imbalanced due to factors such as an unhealthy diet, inadequate digestive enzymes, oral contraceptive use, and various prescription or over-the-counter medications. Plus, it significantly supports women's health by positively influencing vaginal flora.

Research spanning 50 years has demonstrated that fatty acids effectively support gut flora, with Undecylenic Acid recognized as the most potent option available. Clinically proven to maintain a healthy balance of both gastrointestinal and vaginal flora, Thorne’s Undecylenic Acid is six times more effective than caprylic acid, solidifying its position as a top choice for gut health.

Thorne sets the standard for excellence in the supplement industry. Recommended by over 100 professional sports teams and U.S. National Teams, Thorne offers a curated bundle of clean, science-backed supplements and treats designed to fuel your body naturally and effectively. With more than 30 years of dedication to quality, Thorne's commitment to purity and potency begins with sustainably sourced ingredients and rigorous testing. Every supplement undergoes four rounds of testing to ensure optimal absorption, safety, and efficacy, making Thorne the trusted choice for both health-conscious individuals and professionals.

With our Healf Curation Process, we do the work for you. Shop with confidence knowing that every item has been tried, tested, and curated for you.

Learn more about each step—Brand Discovery, Expert Validation, and Community Testing—here.

Undecylenic Acid. Other Ingredients: Extra Virgin Olive Oil, Gelatin (Bovine), Purified Water and Glycerin (Vegetable Source) Gel Cap.

Shipping

At Healf, we prioritize safe and fast delivery for all our customers. Our carefully selected couriers are Royal Mail and DPD.

UK standard delivery

Enjoy free standard delivery on orders above £50, this option usually requires 2-3 working days. If your order is under £50, this delivery option is available for £3.99.

Next working day

For when you need our products urgently, we offer next working day shipping for £5.99. For orders placed before 12.00, we will ship it the same day to ensure you receive your order the next working day.

International

International deliveries can take 7 working days, and up to 4 weeks. The cost is £22.99 for orders below £50, £49.95 for orders above.

Returns

If for any reason you are not satisfied with your order, we provide free 365-day UK returns for all our customers. To initiate your return, simply contact us at team@healf.com, and we'll send you a return slip and help arrange a collection. The item you return must be sent in the same condition as received and inside the original packaging. Once received, we will notify you via email.

For international returns, we unfortunately do not cover the cost. However, we work with an array of carriers and can offer self-posting returns for customers shopping from outside the UK.

Take 5 gelcaps two to three times daily or as recommended by your health professional.

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Frequently asked questions

Every product undergoes our Healf Curation Process. With it, you can shop confidently knowing that every item has been tried and tested before it reaches you. Our Healf Curation Process includes three key steps: Brand Discovery, Expert Validation, and Community Testing. Through these, we assess quality, ingredients, effectiveness, and more, ensuring that every product empowers your wellbeing.

The Healf Journal offers detailed insights into different aspects of wellbeing, as well as guidance, research, recipes, and more to help you invest in your personal wellbeing journey. You can also subscribe to our weekly newsletters for the latest updates at Healf and in the wellbeing industry. Subscribe via the sign-up block at the bottom of this page.

We love people who check ingredients as carefully as we do, so you'll find detailed information about the ingredients used on every product page (where applicable). If you see something you'd like to flag with us or have additional questions, please don't hesitate to get in touch—we'd love to hear from you.

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Our approach keeps us at the forefront of wellbeing. With our global network of health professionals and AI-powered trend analysis, we curate the leading supplements, tools, and tech that pioneer the industry.

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Each product at Healf is carefully examined by a panel of industry specialists—including dieticians, personal trainers, psychologists, and sleep experts—to ensure it meets our high standards for quality, efficacy, and ingredient formulations.

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By collaborating with a dedicated group of customers who test and review each product, we ensure that only those truly beneficial to your wellbeing are offered here at Healf.