White Mulberry Supplement Mimics Diabetes Drugs, Except in Humans

The Oasis Health Journal · Submitted August 5, 2026 · 5:30 PM EDT

By Tito Barragan · Edited by Nadine Cho

White mulberry leaf extract targets the same enzyme as acarbose, a prescription drug for managing blood sugar. Same molecular handshake, same mechanism, same promise on the label. The difference: acarbose went through thirty years of trials in fifty thousand people before the FDA let anyone sell it as medicine. White mulberry supplement went through a handful of small studies, most of them in Asia, and now it sits at the register next to the gum.

The active compound is 1-deoxynojirimycin. Everybody calls it DNJ because nobody wants to say that word twice in one sentence, and honestly, who could blame them.

DNJ is an alpha-glucosidase inhibitor. It blocks the enzyme that cuts complex carbohydrates into glucose in your small intestine. Carbs you cannot break down, you cannot absorb. Glucose you do not absorb does not spike your blood sugar.

That is the theory.

And the theory tested beautifully in horses.

Sixteen Horses, One Month, Zero Complaints

Sixteen horses at risk for insulin dysregulation got escalating doses of DNJ twice a day for twenty-eight days. Researchers fed them sugar water and measured what happened to their insulin. At the highest dose, 5000 milligrams twice daily, peak insulin dropped by thirteen microunits per milliliter when the sugar test happened right after dosing. One hour later, the effect was smaller but still there. Three hours out, gone.

The horses tolerated it fine. No colic, no founder, no digestive revolt, no side effects logged. The trial ran for a month. That is longer than most human studies on this stuff, which tells you exactly where the research dollars go.

Final score: significant. What it proves: DNJ works in horses with intact digestive tracts and a glucose problem.

Those were horses.

Twenty Australians, One Breakfast, One Very Polite Conclusion

The 2026 human crossover was smaller and shorter. Twenty healthy adults in Australia drank either mulberry-and-water-chestnut tea or placebo tea before breakfast, then wore continuous glucose monitors for the rest of the day. The active tea flattened the postprandial glucose spike after breakfast. It also flattened the spike after lunch, four hours later, which they did not see coming. Second-meal effect, documented and unexpected.

Sample size: twenty. Duration: one day per condition. Population: healthy adults with no metabolic disorders whatsoever.

The authors wrote 'these findings should be interpreted with caution' in the conclusion. That is scientist for we are not making any promises and neither should you.

A 2025 meta-analysis tried to pool the evidence. Fifteen randomized controlled trials, 1202 participants, mostly conducted in Asia. White mulberry supplement interventions lowered fasting glucose, HbA1c, insulin resistance, total cholesterol, LDL, triglycerides, and inflammatory markers including TNF-alpha, IL-6 and hs-CRP. The effect sizes were moderate to large. The methodological quality was what you might call mixed, which is peer-review speak for some of these trials were fine and some were held together with prayer.

None of the fifteen trials measured cognitive outcomes, neurovascular outcomes, or anything happening north of the neck. That is awkward because the meta-analysis was framed around vascular dementia risk. They measured blood markers and called it brain protection, which is like measuring tire pressure and calling it a safety inspection.

The benefits were stronger at doses below 500 milligrams per day and treatment durations under twelve weeks. Above that, the curve flattened. Whether that is real biology or just noise from small samples, nobody knows yet.

What This Does Not Establish, A List

No large trial in people with type 2 diabetes. No trial longer than six months. No head-to-head against acarbose, metformin, or any other drug with an actual FDA label and a patient information sheet. No standardized dose, no agreed formulation, no consensus on whether the whole leaf works better than isolated DNJ or worse or the same.

Most studies used extracts standardized to 1 percent or 5 percent DNJ. Some used tea. Some used tablets. One used a yogurt mix. Comparing them is like comparing a beer to a shot to a wine spritzer and calling it alcohol research.

The horse trial dosed at 5000 milligrams twice daily for an animal weighing five hundred kilograms. Scale that to a seventy-kilogram human and you land around 700 milligrams per dose, which is higher than most alpha glucosidase inhibitor supplement products on the market. Whether the lower retail doses do anything in someone who actually has elevated glucose is an open question with no data attached and no trial scheduled.

Also: mulberry allergy is real. Respiratory reactions, contact urticaria, oral allergy syndrome, anaphylaxis in rare cases. All documented. If you react to birch pollen or latex, you might react to mulberry. That is called cross-reactivity, and it does not care how natural the source is or what the influencer said.

What You Can Buy vs What Got Tested, A Gap

Two branded products show up in the clinical discussion: Reducose, a mulberry extract standardized to 5 percent DNJ, and Glubloc, another mulberry preparation with less detail published. Neither has FDA approval as a drug. Both are sold as dietary supplements, which means they cleared a much lower bar. The kind of bar you step over on your way to the register.

The horse trial used Reducose. The human tea trial did not.

If you search white mulberry supplement where to buy, you will find forty products with different extracts, different DNJ percentages, different serving sizes, different label claims, and zero obligation to prove they work the way the studies say mulberry works. Supplements are not required to match the research. They are required not to poison you, which is a lower standard than it sounds.

The market wants to know if white mulberry supplement helps with glucose levels. The studies say maybe, in twenty Australians drinking tea for one day. And yes, in sixteen horses on a high dose for a month. And sort of, in a meta-analysis that pulled fifteen decent trials out of a much larger pile of studies we do not talk about in polite company.

That is not the same as proof. It is early, it is suggestive, it is worth watching.

It is not worth betting your HbA1c on.

Y ya estuvo.

This article is education and reporting on published research. It is not medical advice, and nothing here is intended to diagnose, treat, cure or prevent any disease. Talk to your own clinician about your own situation.

Sources

1. Effects of mulberry leaves & water chestnut husk tea on postprandial and second meal interstitial glucose in healthy adults: A randomised, double-blind, placebo-controlled crossover study, Asia Pacific journal of clinical nutrition (2026).
2. Evaluation of the tolerance and effects of 1-deoxynojirimycin on insulin and glucose dynamics in healthy horses and horses at risk for insulin dysregulation, Journal of veterinary internal medicine (2026).
3. New directions in mulberry leaf research for diabetes: a translational approach based on multi-component synergy, Frontiers in nutrition (2026).
4. Phytochemical Composition, Bioactive Compounds, and Antidiabetic Potential of Four Medicinal Plants Native to the UAE: <i>Capparis spinosa, Citrullus colocynthis, Morus alba</i>, and <i>Rhazya stricta</i>, Biology (2025).
5. Integrative Evidence on Mulberry Extract for Modulating Metabolic Risk Factors Associated with Vascular Dementia, International journal of molecular sciences (2025).
6. Insights into the Activities and Usefulness of Deoxynojirimycin and <i>Morus alba</i>: A Comprehensive Review, Molecules (Basel, Switzerland) (2025).
7. White Mulberry Plant Extracts in Cardiovascular Prevention: An Update, Nutrients (2025).