Glycaemic Index of Honey vs Sugar — The Evidence

What is the glycaemic index of honey compared to table sugar?

The glycaemic index (GI) of honey is generally quoted as around 55-58. Table sugar (sucrose) has a GI of approximately 65. Both are in the medium GI category — defined as 56-69 by the University of Sydney GI database, which is the main international reference.

The GI scale measures how quickly a food raises blood glucose relative to pure glucose (GI of 100). A lower GI means blood glucose rises more slowly after eating that food. Slow rises are generally considered preferable because they avoid the sharp insulin spikes associated with high-GI foods.

The difference between honey's GI of around 58 and sugar's GI of around 65 is real and statistically significant in controlled studies. However, in practical dietary terms, both foods cause a meaningful rise in blood glucose and both are classified as high-sugar foods that should be consumed in moderation.

GI values for honey vary between studies and between honey types — published values range from around 35 for acacia honey to around 74 for some processed honey types. The variation depends on the fructose-to-glucose ratio (more fructose means lower GI), the presence of minor compounds, and whether the honey is raw or processed. Averaging across common honey varieties gives the approximate figure of 55-58.

One important nuance: glycaemic index is measured using a fixed 50g carbohydrate portion, which for honey is a large serving (around 65g of honey). The glycaemic load — which accounts for typical serving size — is often a more useful practical measure. A teaspoon of honey (7g) has a low glycaemic load simply because it is a small quantity, regardless of GI.

Why does honey have a lower GI than sugar if they both contain glucose?

The key is the fructose content. Table sugar is pure sucrose — a 50:50 molecule of glucose and fructose bonded together. In the gut, sucrose is split into equal parts glucose and fructose. Honey contains free glucose and fructose already separated, with fructose typically making up around 38% and glucose around 31% of total weight.

Fructose has a very low GI of around 19. It is metabolised primarily in the liver rather than directly entering the bloodstream, so it causes a smaller immediate rise in blood glucose. Glucose has a GI of 100 — it enters the bloodstream directly and raises blood sugar rapidly.

Honey's higher fructose-to-glucose ratio compared to sucrose is the main reason it has a lower GI. Because more of the sugar in honey is fructose, the overall blood glucose response is lower than for an equivalent amount of sucrose.

Additionally, honey contains small amounts of compounds — organic acids, amino acids, enzymes, and polyphenols — that may slightly slow glucose absorption. Some studies suggest these minor components modestly reduce the rate of gastric emptying or inhibit some digestive enzymes, contributing to a lower GI beyond what fructose content alone explains.

Processed honey tends to have a slightly higher GI than raw honey. One reason is that heat processing can break down fructose and some minor compounds, altering the sugar profile. Another is that raw honey's enzyme activity may influence starch digestion in the gut. The differences between raw and processed honey in GI terms are modest — perhaps 5-10 points — but they go in the direction you would expect.

Does raw honey have a lower GI than processed honey?

The evidence suggests raw honey has a modestly lower GI than highly processed honey, but the differences are small and study numbers are limited.

The proposed mechanisms include: intact enzyme activity in raw honey, which may affect digestion timing; higher organic acid content, which can slow gastric emptying slightly; and better-preserved fructose, since heat processing can convert fructose to glucose or other compounds.

A study published in the Journal of the Academy of Nutrition and Dietetics (2013) compared natural honey to dextrose and found honey produced a lower glycaemic and insulin response. The study used natural, minimally processed honey. Similarly, a randomised crossover trial from 2004 found that processed honey caused higher blood glucose peaks than natural honey in healthy subjects.

However, none of these differences are large enough to move honey from "moderate GI" to "low GI" food in practical terms. Both raw and processed honey raise blood glucose substantially in normal serving sizes, and neither should be treated as a blood-sugar-friendly alternative to sugar for people with diabetes or prediabetes.

The practical implication is that if you are choosing honey for dietary reasons, raw honey is the marginally better choice from a GI perspective, in addition to having more enzymes and polyphenols. But this should not be the primary justification for choosing raw over processed honey — flavour, enzyme preservation, and supporting sustainable beekeeping are more compelling reasons.

How many calories are in honey versus the same weight of sugar?

Per 100g: white sugar contains approximately 400 calories (kcal). Honey contains approximately 300-304 calories per 100g. Honey has fewer calories per gram because it contains around 17-20% water, while sugar contains virtually none.

However, this comparison is often misleading because honey is denser than sugar. A tablespoon holds about 21g of honey but only about 12g of granulated sugar. Per tablespoon, honey therefore delivers more calories than a level tablespoon of sugar — roughly 60-65 kcal for honey versus 48-50 kcal for sugar.

The calorie argument in favour of honey over sugar — that honey is less calorie-dense by weight — is technically true but practically misleading if you substitute honey for sugar volume-for-volume (tablespoon for tablespoon). By volume, honey is more calorific.

If you weigh your sweeteners and use equal masses, honey does provide roughly 25% fewer calories than sugar. Some people switch from sugar to honey in tea or coffee specifically to reduce calorie intake by switching to equal-mass measurements. This works mathematically, but requires weighing rather than spooning.

Both honey and sugar provide calories with minimal protein or fibre. The difference in calorie density is not sufficient to make honey a "diet food". The NHS categorises honey as a free sugar and includes it in the recommendation that adults consume no more than 30g of free sugars daily — the same limit that applies to sugar, syrup, and fruit juice. A tablespoon of honey is approximately 17g of free sugars, more than half the daily limit.

Can diabetics eat honey instead of sugar?

No. Diabetes UK and the NHS both advise people with diabetes to treat honey the same as table sugar — as an added sugar that affects blood glucose and should be counted in daily carbohydrate management.

The lower GI of honey relative to sugar is real but too modest to make practical difference in diabetes management. A person with type 2 diabetes or type 1 diabetes using carbohydrate counting cannot substitute honey for sugar without accounting for the carbohydrates, because honey raises blood glucose substantially in normal serving sizes.

The claim that honey is "safer" for diabetics than sugar because it is natural is not supported by clinical evidence. Natural origin does not determine glycaemic effect. Honey's blood glucose impact is lower than pure glucose but comparable to — and in normal servings, similar to — table sugar. Any food that raises blood glucose requires accounting in a diabetes management plan.

Some diabetics do eat honey in small quantities as part of a controlled diet. This is not inherently problematic as long as it is counted as part of daily carbohydrate intake and blood glucose is monitored appropriately. The issue is substituting honey for sugar on the assumption it is freely safe, which it is not.

For any person with diabetes considering dietary changes, advice from a diabetes nurse, dietitian, or GP is appropriate. Diabetes UK provides dietary guidance specifically for UK patients that is more authoritative on this question than product marketing.