Is Manuka Honey Bad for Diabetics?

Manuka honey is not inherently dangerous for people with diabetes, but it is still a concentrated sugar, and eating it in meaningful quantities can raise blood glucose and worsen long-term glycemic markers. Its glycemic index falls in the moderate range, and some research suggests small amounts of honey may slightly lower fasting glucose compared with table sugar. The picture gets more interesting, though, when you consider that Manuka honey contains unusually high levels of a reactive compound called methylglyoxal, which plays directly into the kind of tissue damage diabetes already accelerates. Whether the benefits outweigh the risks depends heavily on how much you eat, how you use it, and how well your blood sugar is currently managed.

Where Manuka Honey Sits on the Blood Sugar Scale

All honey is roughly 80 percent sugar by weight, mostly glucose and fructose. Manuka is no exception. When tested formally, Manuka honey samples returned glycemic index values between 54 and 59, placing them in the moderate GI category.¹ For comparison, table sugar has a GI of about 65 and pure glucose sits at 100. So Manuka honey does raise blood sugar, just somewhat less sharply than an equal amount of sucrose.

One reason honey tends to produce a gentler glucose spike than refined sugar is its fructose content. Small amounts of fructose prompt the liver to absorb glucose more efficiently by activating an enzyme called glucokinase, which can blunt the immediate blood sugar response.² That mechanism helps explain a separate finding from a head-to-head comparison: when people ate honey instead of an equal-calorie sucrose meal, the honey blunted the postprandial glucose response and delayed the rise of ghrelin, the hunger hormone.³ Hunger ratings and actual food intake afterward were similar between the two, but the metabolic signature looked slightly better with honey.

None of this means Manuka honey is “safe” the way a non-caloric sweetener is safe. It is a concentrated sugar. A tablespoon still delivers roughly 17 grams of carbohydrate, and that carbohydrate still needs to be counted if you are managing insulin doses or carb budgets. The moderate GI simply means the spike is less abrupt, not that it is absent.

The Methylglyoxal Problem

This is where Manuka honey differs from every other honey on your shelf. Its trademark antibacterial punch comes largely from methylglyoxal, or MGO, a reactive compound that forms naturally from the nectar of the Manuka bush. Concentrations in Manuka honey range from about 38 to 828 milligrams per kilogram, levels up to 100 times higher than in conventional honeys.⁴ Those numbers are part of what makes Manuka appealing for wound care and antimicrobial uses, but they create a specific concern for people with diabetes.

MGO is a potent protein-glycating agent. It reacts with proteins in your body and contributes to the formation of advanced glycation end products, commonly called AGEs. These molecules accumulate in tissues over time and are already elevated in people with diabetes due to chronic high blood sugar. AGEs are implicated in the vascular damage, kidney disease, and impaired wound healing that make diabetes so destructive long-term.⁵ Adding a concentrated dietary source of the very compound that drives AGE formation is, at minimum, worth thinking carefully about.⁶

The critical question is how much dietary MGO actually survives digestion and enters the bloodstream. The evidence here is genuinely conflicting. One simulated digestion study found that only 5 to 20 percent of the methylglyoxal in honey survived eight hours of in vitro digestion, leading the researchers to conclude it exerts essentially no influence on MGO levels in the body.⁷ A more recent study using a different digestion model, however, found that 28 to 69 percent of dietary MGO was passively absorbed, depending on what other foods were eaten alongside it.⁸ The gap between “barely any gets through” and “up to two-thirds gets absorbed” is enormous, and researchers have not settled it yet. The body does have its own MGO detoxification system, but that system is often impaired in people with diabetes, which makes the uncertainty more consequential for this group specifically.

What Happens When Diabetics Actually Eat Honey

A large meta-analysis pooling data from 20 clinical trials found that oral honey intake was associated with a small but statistically significant drop in fasting blood glucose, roughly 0.2 mmol/L on average.⁹ That sounds encouraging, but the effect was modest and the studies varied widely in design, honey type, and dose. The meta-analysis covered honey broadly, not Manuka specifically, and the variability between individual trials was substantial.

When you zoom in on studies focused on people with type 2 diabetes, the picture gets less optimistic. A randomized crossover trial that gave diabetic participants 50 grams of honey per day for eight weeks found that HbA1c, the key marker of longer-term blood sugar control, increased by 0.17 percent in the honey condition. In the control condition without honey, HbA1c actually decreased by 0.22 percent, and the difference between the two was statistically significant.¹⁰ Fifty grams is roughly two and a half tablespoons, which is not an unreasonable daily amount for someone who uses honey in tea, yogurt, and cooking.

A systematic review examining honey consumption in diabetic versus non-diabetic adults reached a similar cautionary note: high honey intake may increase glucose levels and worsen other metabolic markers in people with type 2 diabetes, though the authors noted that substantial differences in study design limited the strength of the conclusion.¹¹ Interestingly, the same review found that honey had no significant effect on metabolic profiles in non-diabetic people. The implication is that honey’s metabolic impact is not the same for everyone: if your glucose metabolism is already compromised, the added sugar load matters more.

One eight-week trial that tested honey in diabetic patients did find some favorable lipid changes, including decreases in total cholesterol, LDL cholesterol, and triglycerides along with an increase in HDL cholesterol.¹² So the metabolic trade-offs are real: honey may help some cardiovascular risk markers while simultaneously making blood sugar control harder. Which effect matters more depends on the individual and on what else is happening in their treatment plan.

Topical Use Is a Different Story

If you are thinking about Manuka honey not as a food but as a wound treatment, the calculus changes substantially. Diabetic foot ulcers are one of the most dangerous complications of diabetes, and there is solid clinical evidence that Manuka honey dressings can speed healing and disinfection. In a randomized trial comparing Manuka honey-impregnated dressings to conventional dressings for neuropathic diabetic foot ulcers, the honey group healed in an average of 31 days compared with 43 days in the conventional group. About 78 percent of ulcers in the honey group became sterile within the first week, compared with roughly 36 percent in the control group.¹³

A common concern is whether applying honey to a wound might raise blood sugar through absorption. Clinical evidence says it does not. Topical use of medical-grade honey on diabetic foot ulcers has been found to be safe in terms of blood glucose levels.¹⁴ The amount of sugar absorbed through a wound dressing is negligible compared with what you would eat. For diabetic wound care, the antimicrobial properties of Manuka honey seem to outweigh the theoretical risk of the methylglyoxal content, though some researchers have raised the concern that MGO in honey could contribute to the AGE accumulation that impairs wound healing in the first place.⁵ The clinical trial data, at least, suggests the healing benefits win out.

Anti-Inflammatory and Antioxidant Effects in Animal Models

Much of the enthusiasm around Manuka honey and diabetes comes from animal research that paints a more hopeful picture than the human trials. In diabetic rat models, Manuka honey has been shown to reduce markers of oxidative stress, improve pancreatic islet architecture, and upregulate transcription factors associated with tissue regeneration.² In another animal study, honey and propolis ameliorated kidney and liver damage caused by high glucose, reducing markers of oxidative damage and improving tissue histology.¹⁵

Honey, including Manuka, has also been found to reduce pro-inflammatory cytokines in diabetic models, potentially by inhibiting a key inflammatory signaling pathway. Studies have shown reductions in TNF-alpha, IL-6, and IL-1-beta along with increases in anti-inflammatory IL-10.¹⁶ This matters because chronic low-grade inflammation is a hallmark of type 2 diabetes and drives many of its complications.

The obvious caveat is that rat pancreases and human metabolic systems are not the same thing. The doses used in animal studies often do not translate directly, and the controlled conditions of a lab say little about how honey fits into the chaotic reality of a person’s whole diet. These findings are intriguing starting points for research, not clinical recommendations.

How Much Is Too Much

Portion size is probably the single biggest practical variable. The crossover trial that showed worsening HbA1c used 50 grams of honey per day, which adds up to roughly 40 grams of carbohydrate and about 150 calories from sugar alone. That is a significant chunk of any diabetic meal plan. Smaller amounts, say a teaspoon in tea, deliver around 6 grams of carbohydrate and are unlikely to cause meaningful glycemic disruption for most people on a well-managed treatment plan, provided they account for it in their carb count.

The meta-analysis that found a modest fasting glucose reduction included studies using a wide range of doses and durations, but the signal tended to be better in studies using lower or moderate amounts of honey.⁹ The systematic review that flagged worsening metabolic parameters specifically noted that “high intake” was the problem, not honey per se.¹¹ There seems to be a dose-response pattern where small quantities may be metabolically neutral or mildly beneficial, while larger amounts overwhelm whatever modest advantages honey’s fructose content and bioactive compounds provide.

If you have diabetes and want to use Manuka honey, treating it exactly like any other added sugar in your diet is the most sensible approach. Count the carbs, keep the portions small, monitor your blood sugar response, and do not assume the antioxidant or antimicrobial properties give you a free pass on the sugar content.

The Adulteration Problem

Manuka honey is one of the most expensive honeys on the market, which makes it one of the most frequently adulterated. Cheap corn syrup, rice syrup, or other sweeteners are sometimes blended with genuine honey and sold at premium prices. This matters for anyone, but for people with diabetes, adulterated honey is a particularly bad deal: you get all the blood sugar impact of added refined sugars with none of the bioactive compounds that might offer mild compensatory benefits. Honey adulteration has been linked to greater blood sugar spikes, increased lipid levels, and higher blood pressure compared with genuine honey.¹⁷

New Zealand and Australia have implemented grading systems for Manuka honey based on MGO content and other markers like leptosperin. If you are buying Manuka honey specifically for its purported benefits, looking for a UMF (Unique Manuka Factor) or MGO rating from a certified producer is one way to reduce the chance of getting a diluted product. That said, even genuine Manuka honey with a high UMF rating is still sugar, and the MGO that makes it genuine is the same MGO that raises the AGE concern discussed earlier. Higher-rated Manuka honey contains more of both the therapeutic and the potentially harmful compound.

What Manuka Honey Does to Gut Bacteria

There has been growing interest in whether honey’s oligosaccharides and antimicrobial compounds affect the gut microbiome in ways that could matter for metabolic health. The results so far are underwhelming. A mouse study found that feeding Manuka honey produced minimal changes to the gut microbial community and no significant increase in beneficial Bifidobacteria populations.¹⁸ The researchers noted that most of the honey’s sugars and active compounds are digested and absorbed in the upper gut, leaving little to reach the colon where the bulk of the microbiome lives.

A more promising angle involves combining Manuka honey with alpha-cyclodextrin, a fiber-like compound that protects some honey components through digestion and delivers them to the lower gut. That combination increased the availability of substrates for beneficial bacteria, promoted Lactobacillus growth, and inhibited Salmonella in an in vitro fermentation model.¹⁹ This is a lab result, not a clinical finding, and the formulation involved is not what you would get from a jar of Manuka honey on its own. For now, the microbiome angle is an area of active research with no actionable conclusion for people managing diabetes.

1
e-SPEN Journal. The glycaemic index of Manuka honey
2
PubMed Central. Pancreatic regenerative potential of manuka honey evidenced through pancreatic histology and levels of transcription factors in diabetic rat model
3
PubMed. Effect of honey versus sucrose on appetite, appetite-regulating hormones, and postmeal thermogenesis
4
PubMed. Isolation by HPLC and characterisation of the bioactive fraction of New Zealand manuka (Leptospermum scoparium) honey
5
PubMed Central. Methylglyoxal-a potential risk factor of manuka honey in healing of diabetic ulcers
6
Food Chemistry. An updated review of functional ingredients of Manuka honey and their value-added innovations
7
PubMed. Metabolic transit of dietary methylglyoxal
8
PubMed Central. Glycation reactions of methylglyoxal during digestion in a dynamic, in vitro model of the upper gastrointestinal tract (TIM-1)
9
Nutrition Reviews. Effect of honey on cardiometabolic risk factors: a systematic review and meta-analysis
10
PubMed Central. Effect of Natural Honey on Glycemic Control and Anthropometric Measures of Patients with Type 2 Diabetes: A Randomized Controlled Crossover Trial
11
PubMed Central. The Effects of Oral Consumption of Honey on Key Metabolic Profiles in Adult Patients with Type 2 Diabetes Mellitus and Nondiabetic Individuals: A Systematic Review of Clinical Trials
12
PubMed. Effects of natural honey consumption in diabetic patients: an 8-week randomized clinical trial
13
PubMed Central. Manuka honey-impregnated dressings in the treatment of neuropathic diabetic foot ulcers
14
Journal of Aging Research and Lifestyle. Management of Wounds in the Elderly: A Comparison of Medical-Grade Honey Products with Other Wound Care Products
15
PubMed Central. Effect of propolis and honey in hyperglycemia-induced kidney and liver injuries, proteinuria, and oxidant and antioxidant parameters
16
PubMed. The effects of honey on pro- and anti-inflammatory cytokines: A narrative review
17
PubMed Central. The Toxic Impact of Honey Adulteration: A Review
18
PeerJ. Consumption of antimicrobial manuka honey does not significantly perturb the microbiota in the hind gut of mice
19
Journal of Functional Foods. Metabolic and microbial responses to the complexation of manuka honey with α-cyclodextrin after simulated gastrointestinal digestion and fermentation