Is the insulin index the same as the glycemic index?

No. The Glycemic Index (GI) measures how much a food raises blood glucose, using a portion containing 50 g of digestible carbohydrate. The Food Insulin Index measures how much a food raises blood insulin, using a 1,000 kJ (239 kcal) portion. The key difference is that II captures the insulin response from all macronutrients — protein and fat also stimulate insulin — while GI only measures carbohydrate effects on glucose.

Can a food have a low glycemic index but a high insulin index?

Yes, and this is one of the most important insights from FII research. Lean beef and fish have essentially no glycemic index (they contain no digestible carbohydrates), yet they produce a meaningful insulin response due to insulinogenic amino acids. Conversely, some high-fat bakery products may have a lower GI (fat slows glucose absorption) but a higher insulin index because refined carbohydrates combined with fat trigger a disproportionate insulin response.

Should people with diabetes use the insulin index?

The II can be a valuable supplementary tool for people with both type 1 and type 2 diabetes. For type 1 diabetes, it can help refine meal-time insulin dosing beyond carbohydrate counting alone — particularly for protein- and fat-heavy meals. For type 2 diabetes and insulin resistance, choosing low-FII foods may help reduce the burden on the pancreas and improve insulin sensitivity over time. Always implement dietary changes with the guidance of your healthcare team.

What is the best low-insulin-index breakfast?

Based on the available II data, one of the lowest-insulin-index breakfast combinations is eggs cooked in olive oil or butter, paired with steel-cut oats or all-bran cereal. Eggs score around 31, while oatmeal scores around 40. Adding a small handful of peanuts or almonds lowers the overall meal insulin demand further. Avoid fruit juice, sweetened cereals, and flavored low-fat yogurts at breakfast — these score significantly higher on the insulin index.

Why do potatoes have a higher insulin index than white bread?

Boiled potatoes score approximately 121 on the insulin index — higher than white bread (100). Potato starch is highly digestible when cooked, leading to rapid glucose release and a strong insulin response. White bread, while refined, contains some protein from wheat gluten and a different starch structure that slightly moderates the response. You can lower the insulin impact of potatoes by cooling them after cooking (which converts some starch to resistant starch) or by eating them with protein and fat.

Is a low-insulin-index diet the same as a low-carb diet?

Not exactly. While reducing high-GI refined carbohydrates does lower insulin demand, the II reveals a more nuanced picture. Pasta scores low despite being carbohydrate-rich. Legumes and oatmeal score moderately despite containing substantial carbohydrates. Conversely, lean meats and fish — carbohydrate-free foods — still produce a meaningful insulin response. A low-II diet focuses on the quality and combination of foods, not simply on eliminating carbohydrates.

Insulin Index of Drinks — InsulinGuru

Insulin Index Guide

Insulin Index of Drinks: The Complete Guide

From morning coffee to evening wine — here is exactly how different beverages trigger your insulin response, and what that means for your metabolic health.

InsulinGuru Research Team

insulinguru.com

| Updated: April 2026 | 12 min read | Evidence-based

What is the insulin index — and why does it matter for drinks?

Most people are familiar with the glycemic index (GI), which measures how quickly a food raises blood glucose. The insulin index (II) goes one step further: it measures the actual insulin response a food or drink triggers over a two-hour period, relative to a reference portion of white bread (set at 100).

This distinction is critically important when it comes to beverages. Some drinks — particularly those with dairy proteins or certain amino acids — can provoke a significant insulin spike even when they contain little or no sugar. Other drinks, like unsweetened green tea or water, produce virtually no insulin response at all.

Key insight

Many liquids are consumed without much thought about their metabolic impact. Yet a large latte, a glass of orange juice, or a can of cola can each spike insulin to levels comparable to a full meal — even if they feel like "just a drink."

How the insulin index is measured

II = (insulin AUC of food ÷ insulin AUC of white bread) × 100

AUC = area under the curve over 120 minutes post-consumption. The reference food (white bread, 1000 kJ portion) is set to II = 100. A score of 50 means the tested drink provokes half the insulin response of white bread.

For people managing type 2 diabetes, insulin resistance, PCOS, or simply trying to improve metabolic health and body composition, understanding the insulin index of beverages is a highly practical tool. Drinks are often consumed multiple times per day, meaning even a modest reduction in insulin-spiking beverages can have a meaningful cumulative effect.

How to read the insulin index scale

The insulin index uses the same 0–100+ scale regardless of food category. Here is how we classify drinks on this site:

0 – 40 Low

41 – 69 Moderate

70+ High

Scores are benchmarked against white bread (II = 100) using a standard 1000 kJ portion equivalent.

One important note: the insulin index of a drink can shift based on what is consumed alongside it. Drinking a high-II juice alongside fat and protein (as part of a mixed meal) will generally blunt the insulin response compared to drinking it in isolation. Context matters.

Complete insulin index table for drinks

The table below covers the most commonly consumed beverages, organised by category. All scores reflect the drink consumed in a standard serving (~240–250 ml) without food, unless noted. Use the category filters to find drinks quickly.

Insulin Index of Drinks Source: insulinguru.com database · 2026

Drink	II Score	Response level	Category

Data note

Insulin index values for beverages are derived from published human studies and extrapolated from known macronutrient composition where direct measurements are unavailable. Values should be treated as evidence-based estimates. Individual responses may vary depending on gut microbiome, metabolic status, and meal context.

Fruit and vegetable juices

Fruit juices consistently rank among the highest-insulin beverages despite being widely perceived as healthy. The juicing process removes virtually all dietary fibre, which normally slows glucose absorption and moderates insulin release. What remains is a concentrated solution of rapidly absorbed sugars — predominantly fructose and sucrose — that enters the bloodstream very quickly.

A 250 ml glass of grape juice or mango juice (II ≈ 75) can provoke an insulin response approaching that of white bread. Orange juice (II ≈ 70) and apple juice (II ≈ 65) are only marginally better. Even cranberry juice — often marketed as a health drink — registers a moderate-to-high II of around 60 due to its added sugar content in most commercial preparations.

"The problem with fruit juice is not the fruit — it is the removal of fibre. Whole fruit has an insulin index far lower than its juice equivalent because fibre slows gastric emptying and attenuates the insulin response. Drinking a glass of orange juice is metabolically very different from eating two oranges."

InsulinGuru Research Team

Based on Holt et al. (1997) and subsequent fibre research

Tomato juice is a significant outlier in this category. With an insulin index of approximately 38, it falls into the low range — thanks to its low sugar content, high fibre retention, and the presence of umami compounds. It is one of the few commercially available juices that can be consumed without a significant insulin spike.

Best choice in this category

Tomato juice (II ≈ 38) is by far the lowest-insulin juice option. Unsweetened vegetable juices in general — cucumber, celery, spinach — tend to have insulin indices below 30. If you enjoy fruit juice, diluting it 50/50 with still water can meaningfully reduce the insulin load.

Coffee drinks: a wide range of insulin responses

Plain black coffee and espresso (without sugar) have a remarkably low insulin index — around 5 — making them among the most metabolically benign beverages available. Caffeine has a mild stimulating effect on metabolism and, at typical doses, does not meaningfully raise insulin in isolation.

However, the moment milk enters the equation, the insulin index rises substantially. This is due to the dairy protein effect: whey and casein proteins in milk are highly insulinogenic, independent of lactose content. This is one of the most important and frequently misunderstood aspects of coffee and insulin.

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Espresso / Black coffee

II ≈ 5. Negligible insulin response. The reference drink for coffee drinkers concerned with metabolic health.

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Flat white / Americano with milk

II ≈ 35. A moderate amount of milk. Better than a full latte, but the dairy protein effect is already present.

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Cappuccino / Latte

II ≈ 40–45. The larger volume of milk raises the score into moderate territory. Even without sugar.

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Raf coffee (unsweetened)

II ≈ 60. The combination of cream and milk in raf coffee pushes it into the higher moderate range, even before adding any sweetener.

Decaffeinated coffee has a similarly low insulin index (II ≈ 5) to regular black coffee, suggesting the insulin response is driven by the milk and sugar additions rather than caffeine itself. This makes decaf a valid option for those who are caffeine-sensitive but still want a low-II hot drink.

Watch out for

Sweetened coffee drinks — flavoured lattes, frappuccinos, and syrup-laden iced coffees from café chains — can easily reach II scores of 80–100 or higher once the added sugar load is factored in. The values in our table assume no added sugar.

Alcoholic beverages and the insulin response

The relationship between alcohol and insulin is nuanced. Pure ethanol does not itself stimulate significant insulin secretion — in fact, it can temporarily suppress hepatic glucose output and lower blood sugar, particularly in a fasted state. However, the sugar, carbohydrate, and mixer content of alcoholic drinks determines their insulin index profile very directly.

Dry red wine scores approximately 0 on the insulin index. With minimal residual sugar (typically 2–4 g/L) and no significant insulinogenic proteins, dry wine consumed in moderation has one of the lowest insulin impacts of any widely consumed beverage. The polyphenols in red wine — resveratrol and others — may even have mild insulin-sensitising properties, though the evidence remains preliminary.

Champagne and semi-sweet wines have slightly higher scores (II ≈ 10) due to their residual sugar content. Sweet wines (II ≈ 20) are meaningfully higher. Spirits like gin, vodka, and whisky — consumed neat or with zero-calorie mixers — have an insulin index near zero, though mixing them with juice or regular tonic water rapidly changes the picture.

Important caveat

A low insulin index does not make alcohol a health food. Alcohol impairs liver function, disrupts sleep quality (which has significant downstream effects on insulin sensitivity), and provides empty calories. The II scores here reflect acute insulin signalling only, not overall metabolic health impact.

Beer is absent from our primary table because its insulin response varies considerably by style — light lagers sit around II 35–45, while sweet stouts and IPAs can reach 60+. We will cover beer in a dedicated article.

Sodas and sweetened drinks

It will surprise very few readers to learn that Coca-Cola, Pepsi, and similar full-sugar carbonated drinks score very high on the insulin index — around 90. A 250 ml serving contains roughly 26–28 g of rapidly absorbed sugars, producing a sharp blood glucose and insulin spike within 15–30 minutes of consumption.

What makes sodas particularly problematic from an insulin standpoint is the combination of high sugar load, liquid form (no fibre or fat to slow absorption), and the fact that they are rarely consumed as an isolated drink — they often accompany meals that are already high in processed carbohydrates, compounding the insulin response.

Diet sodas: a separate question

Diet versions of cola drinks (containing aspartame, sucralose, or acesulfame K) have an insulin index close to zero in most studies. However, the long-term relationship between artificial sweeteners and insulin sensitivity, gut microbiome health, and cephalic phase insulin release (the brain triggering insulin release in response to sweet taste) is still an active area of research. They are preferable to regular sodas from an acute insulin standpoint, but not a perfect solution.

Practical tips for lower-insulin drinking throughout the day

Shifting your daily beverage choices can be one of the most impactful dietary changes you make for insulin management, precisely because drinks are consumed so frequently and often without awareness of their metabolic cost. Here are the most evidence-supported strategies:

Start mornings with black coffee or tea Espresso, Americano, or green tea (II ≈ 5–10) are ideal morning drinks. Delay adding milk until your body has moved past the fasted, insulin-sensitive state of early morning.

Replace juice with whole fruit A whole orange has an insulin index roughly 40–50% lower than a glass of orange juice, thanks to intact fibre. The fibre slows gastric emptying and attenuates the glucose curve.

Pair higher-II drinks with food Consuming a moderate-II juice alongside a meal containing fat and protein blunts the insulin response significantly compared to drinking it alone on an empty stomach.

Dilute juices and choose smaller portions A 50/50 dilution of apple juice with still water roughly halves the insulin load while preserving much of the flavour. Smaller portions also reduce total insulin stimulus.

Choose tomato juice over fruit juice At II ≈ 38, unsweetened tomato juice is the only commercially available juice in the low range. It is rich in lycopene, potassium, and vitamin C — a genuinely better option.

Opt for dry wine over sweet wine or beer If you drink alcohol, dry red or white wine (II 0–5) has a far lower insulin impact than sweet wines, cocktails, or beer with high residual sugar.

The best low-insulin drinks at a glance

If you want to keep your insulin response minimal throughout the day, the following drinks are your safest choices: still and sparkling water, black coffee, espresso, decaf coffee, unsweetened green and black tea, unsweetened herbal teas, and dry red or white wine (if you drink alcohol). All of these fall below II 10.

Frequently asked questions

Does milk in coffee spike insulin even without sugar? +

Yes — this is one of the most practically important findings in insulin index research. Dairy proteins (particularly whey) are among the most insulinogenic nutrients known, independent of their effect on blood glucose. A plain latte with no added sugar (II ≈ 45) provokes a meaningful insulin response purely due to the milk proteins and lactose. The effect is proportional to the volume of milk used, which is why a flat white (less milk) has a lower II than a large latte.

Does the insulin index of juice change if I drink it slowly? +

Yes, modestly. Sipping juice slowly over 20–30 minutes, rather than drinking it in one go, spreads the glucose absorption and can reduce the peak insulin response. However, the total insulin area-under-the-curve (AUC) — which is what the insulin index measures — will be similar. Rate of consumption matters more for glucose peaks than for total insulin exposure.

Is sparkling water the same as still water for insulin? +

Yes. Plain sparkling water (carbonated water with no added flavours, sweeteners, or sugars) has a negligible insulin index, essentially identical to still water. Flavoured sparkling waters with added sugars or syrups are a different matter — always check the label. Natural mineral waters, flavoured with fruit infusion but no added sugar, generally remain very low on the insulin index.

Why does dry wine have an insulin index of 0? +

Dry wine contains very little residual sugar (typically 2–4 g per glass for red wine), no protein, and no significant carbohydrate that would stimulate insulin secretion. Ethanol itself does not trigger insulin release — in fact, it transiently inhibits hepatic glucose production. The insulin index of 0 for dry red wine reflects the acute two-hour measurement. It does not mean wine is metabolically neutral in the long term: regular alcohol consumption has complex effects on liver function, sleep, and metabolic health.

What is the lowest-insulin hot drink? +

Black coffee, espresso, and decaffeinated coffee (all II ≈ 5) are the lowest-insulin hot drinks commonly consumed. Unsweetened green tea, black tea, and herbal teas also have insulin indices at or near zero. Once milk, cream, or any sweetener is added, the score rises. For comparison, a matcha latte made with oat milk can easily reach II 50–60 depending on preparation.

How does orange juice compare to a whole orange for insulin? +

A significant difference exists. A glass of orange juice (250 ml) has an insulin index of approximately 70. A medium whole orange has an insulin index of roughly 35–40, around half that of its juice equivalent. The fibre in the whole fruit — particularly soluble fibre and the intact cell structure — slows glucose absorption and moderates the insulin response. This principle applies to virtually all fruits versus their juice equivalents.

Key takeaways

✓

Water, black coffee, and tea are your baselineAll score below II 10 and can be consumed freely without insulin concerns.

Fruit juices are not as benign as they seemMost score II 60–75, comparable to many processed foods, due to absent fibre.

Milk in coffee mattersEven unsweetened lattes and cappuccinos sit at II 40–45 due to dairy proteins.

✓

Dry wine is low; sodas are highDry red wine (II 0) and dry spirits (II 0) are the lowest-insulin alcoholic options. Sodas (II 90) are among the highest.

References and further reading

Holt SHA, Brand-Miller JC, Petocz P. An insulin index of foods: the insulin demand generated by 1000-kJ portions of common foods. Am J Clin Nutr. 1997;66(5):1264–1276.
Bell KJ, Smart CE, Steil GM, Brand-Miller JC, King B, Wolpert HA. Impact of fat, protein, and glycemic index on postprandial glucose control in type 1 diabetes. Diabetes Care. 2015;38(6):1008–1015.
Ostman EM, Liljeberg Elmståhl HG, Björck IM. Inconsistency between glycemic and insulinemic responses to regular and fermented milk products. Am J Clin Nutr. 2001;74(1):96–100.
Ercan N, Nuttall FQ, Gannon MC, et al. Effects of glucose, galactose, and lactose ingestion on the plasma glucose and insulin response in persons with non-insulin-dependent diabetes mellitus. Metabolism. 1993;42(12):1560–1567.
Muraki I, Imamura F, Manson JE, et al. Fruit consumption and risk of type 2 diabetes: results from three prospective longitudinal cohort studies. BMJ. 2013;347:f5001.
Schrieks IC, Heil AL, Hendriks HF, Mukamal KJ, Beulens JW. The effect of alcohol consumption on insulin sensitivity and glycemic status. Diabetes Care. 2015;38(4):723–732.
InsulinGuru Database. Insulin Index of Common Beverages. insulinguru.com, 2026. Derived from published studies and macronutrient modelling.