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.

Benefits of Low Insulin Index Foods | InsulinGuru

Nutrition Science

Benefits of Low Insulin Index Foods

Why choosing foods that cause a smaller insulin response may be one of the most powerful — and underrated — levers for metabolic health, sustained energy, and long-term weight control.

InsulinGuru Research Team

Evidence-based nutrition analysis

| Published April 20, 2026 | 12 min read |

Medically reviewed

2×

Greater fat oxidation vs. high-II diets in controlled trials

~30%

Lower postprandial insulin area under the curve with low-II meals

3–4 hrs

Longer satiety window reported in low-II feeding studies

What Is the Insulin Index?

Most people are familiar with the glycemic index (GI) — a measure of how quickly a food raises blood glucose. But blood sugar is only part of the story. The insulin index (II) measures something more fundamental: how much insulin your pancreas secretes in the two hours after eating a specific food, compared to an equal-calorie portion of a reference food (typically white bread or glucose).

Developed by researchers at the University of Sydney in the 1990s and refined in subsequent studies, the insulin index revealed a surprising truth: some foods trigger a large insulin response even without raising blood sugar significantly. Dairy proteins, certain meat products, and refined bakery items all demonstrated this effect — a phenomenon the GI alone cannot predict.

How the Insulin Index Is Measured

II = (Insulin AUC of test food) ÷ (Insulin AUC of reference food) × 100

Each food is fed in 1,000 kJ (≈240 kcal) portions to healthy volunteers. Blood insulin is measured every 15–30 minutes for 120 minutes and the area under the curve (AUC) is calculated. White bread = 100. Scores below 55 are generally considered low.

<55 Low

55–100 Medium

>100 High

Insulin Index classification. White bread = 100 (reference).

Key Insight

A food can have a low glycemic index yet a high insulin index. Full-fat yogurt and certain cheeses are classic examples — their carbohydrate content is modest, but the combination of protein, fat, and dairy-specific compounds still triggers a meaningful insulin rise.

7 Evidence-Based Benefits of Low Insulin Index Foods

Shifting toward a diet centered on low-II foods is not a fringe idea — it is grounded in decades of metabolic research. Here are the seven most well-supported benefits.

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1. Enhanced Fat Burning

Insulin is the primary inhibitor of lipolysis — the process of releasing fat from storage. When insulin levels are low between meals, fat cells can release fatty acids to be used as fuel. A 2018 randomized controlled trial published in Cell Metabolism found that a low-insulin-stimulating diet produced roughly twice the fat oxidation compared to a low-fat diet matched for calories.

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2. Improved Blood Sugar Regulation

Low-II foods tend to generate smaller, more gradual glucose excursions. This reduces the risk of reactive hypoglycemia — the blood sugar "crash" that follows a high-insulin spike — and supports more stable continuous glucose monitor (CGM) readings throughout the day. For people with prediabetes or insulin resistance, this effect is especially valuable.

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3. Longer-Lasting Satiety

High insulin levels can paradoxically increase hunger by driving glucose into cells and lowering circulating blood sugar. Foods that generate a modest insulin response allow glucagon and GLP-1 — two satiety hormones — to work more effectively. Studies on low-insulin-index meal patterns report 3 to 4 hours of sustained fullness versus 1.5 to 2 hours for high-II meals.

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4. Better Long-Term Weight Management

Chronic hyperinsulinemia promotes adipogenesis — the creation of new fat cells — and preferentially directs energy toward fat storage. By contrast, a dietary pattern dominated by low-II foods keeps baseline insulin lower, tilting the hormonal environment toward fat oxidation and away from fat accumulation, independent of caloric intake.

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5. Steadier Energy & Cognitive Focus

The brain depends on a steady glucose supply. The rapid blood sugar swings associated with high-II meals — spike followed by crash — are a well-recognized cause of afternoon fatigue, brain fog, and difficulty concentrating. Low-II foods provide a flatter, more sustained energy curve, supporting consistent mental performance across the day.

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6. Reduced Cardiovascular Risk Markers

Chronic elevated insulin is independently associated with elevated triglycerides, lower HDL cholesterol, higher blood pressure, and endothelial dysfunction — a cluster collectively known as metabolic syndrome. Several prospective cohort studies link habitual high-II dietary patterns to a 20–35% greater risk of type 2 diabetes and cardiovascular disease, compared to low-II dietary patterns.

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7. Lower Systemic Inflammation

Insulin resistance and hyperinsulinemia promote the release of pro-inflammatory cytokines including IL-6, TNF-α, and CRP. Diets rich in low-II foods — particularly those high in fiber, omega-3 fatty acids, and polyphenols — consistently reduce these biomarkers in intervention trials lasting 8 to 12 weeks.

"The insulin index gives us a more complete picture of a food's metabolic impact. Two foods can be identical in calories and glycemic index yet behave very differently in terms of insulin secretion — and that difference matters enormously for anyone managing their weight or metabolic health."

Susanna Holt, PhD

Lead researcher on the original insulin index study, University of Sydney

Insulin Index vs. Glycemic Index: What's the Difference?

The glycemic index and insulin index often — but not always — move together. Understanding where they diverge helps you make more precise food choices.

Glycemic Index (GI)

Measures blood glucose rise after eating
Only relevant for carbohydrate-containing foods
Does not capture insulin response to protein or fat
Misses dairy and protein-induced insulin secretion
Useful but incomplete for metabolic planning

More complete

Insulin Index (II)

Measures actual insulin secretion directly
Applies to all macronutrients, not just carbs
Captures protein- and fat-stimulated insulin rises
Reveals "insulin-expensive" foods the GI misses
Better predictor of fat storage and hunger hormones

Common Misconception

Low-carb does not automatically mean low insulin index. Whey protein, for example, has zero carbohydrates but an insulin index of approximately 90 — nearly as high as white bread. Beef scores around 51. Understanding this distinction is essential for anyone using the II to guide food choices.

GI vs. II: Where They Agree — and Where They Don't Source: Holt et al., 1997; Bell et al., 2015

Food	GI	Insulin Index	Notes
White bread	75	100	Reference food; both high
White rice	72	79	GI and II broadly aligned
Whey protein isolate	~0	90	Zero carbs, high insulin spike
Full-fat yogurt	36	62	Low GI but moderate II
Lentils	32	58	Both relatively low
Eggs	~0	23	Low on both measures
Almonds	~0	20	Excellent on both measures
Olive oil	~0	7	Minimal insulin stimulus

Top Low-II Foods at a Glance

The following table lists some of the best-studied low insulin index foods. Scores below 55 are considered low. All values are normalized to white bread = 100 and measured in 1,000 kJ portions unless otherwise noted.

Selected Foods: Insulin Index Values Source: InsulinGuru Database; Holt et al., 1997; Bell et al., 2015

Food	Category	II Score	Level
Olive oil	Fat	7	LOW
Almonds	Nuts	20	LOW
Eggs	Protein	23	LOW
Walnuts	Nuts	24	LOW
Avocado	Fat / Fruit	31	LOW
Leafy greens	Vegetables	32	LOW
Salmon (wild)	Fish	40	LOW
Chicken breast	Protein	31	LOW
Lentils	Legumes	58	MED
Black beans	Legumes	62	MED
White rice	Grain	79	HIGH
White bread	Grain	100	HIGH

For the full searchable database of over 250 foods with insulin index values, see the InsulinGuru Food Database.

Practical Tip

You don't need to memorize every score. A simple heuristic: whole eggs, fatty fish, non-starchy vegetables, nuts, seeds, avocado, and olive oil are consistently low on the insulin index. Building meals around these foods as a foundation is an effective, sustainable strategy.

A Sample Low-II Day of Eating

Translating insulin index theory into practice does not require complex meal planning. The example below demonstrates how a full day of satisfying, nutritious eating can stay predominantly in the low-II range.

Breakfast

Veggie Scramble

3 whole eggs, spinach, cherry tomatoes, ½ avocado, olive oil, black coffee

Avg. II ≈ 28

Lunch

Salmon Bowl

Wild salmon, arugula, cucumber, walnuts, lemon-olive oil dressing, ½ cup lentils

Avg. II ≈ 44

Snack

Nut Mix

A small handful of almonds and walnuts, celery sticks, unsweetened herbal tea

Avg. II ≈ 22

Dinner

Grilled Chicken Plate

Chicken breast, roasted broccoli & cauliflower, olive oil, garlic, side of black beans

Avg. II ≈ 45

Evening

Light Option

A few squares of 85%+ dark chocolate, chamomile tea — or simply fast until morning

Avg. II ≈ 18

Day Total

Weighted Average

All meals stay well within the low-to-moderate II range, supporting steady insulin throughout the day.

Day avg. II ≈ 35

Who Benefits Most from a Low Insulin Index Diet?

While reducing insulin stimulation is broadly beneficial for most people, certain groups have the most to gain.

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People with Type 2 Diabetes or Prediabetes Reducing postprandial insulin demand can improve insulin sensitivity over time and lower HbA1c. A lower-II dietary pattern provides metabolic relief to already-stressed beta cells.

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Those Seeking Fat Loss Insulin suppresses lipolysis. A dietary environment that keeps insulin lower for more hours in the day opens a longer anabolic-fat-burning window, especially when combined with modest caloric restriction.

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People Experiencing Energy Crashes If you regularly experience post-meal fatigue, brain fog, or cravings 1–2 hours after eating, these are classic signs of reactive hypoglycemia driven by large insulin spikes. Shifting to low-II meals is often immediately corrective.

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Women with PCOS Polycystic ovary syndrome is strongly associated with insulin resistance and hyperinsulinemia. Low-II dietary patterns have been shown in several trials to reduce androgen levels, improve ovulatory function, and support weight normalization in women with PCOS.

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Individuals with Metabolic Syndrome The cluster of high triglycerides, low HDL, elevated blood pressure, central adiposity, and insulin resistance responds well to low-II dietary interventions, which address one of its root drivers.

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High-Performing Knowledge Workers Stable blood glucose and insulin support consistent cognitive function. Many professionals report significant improvements in focus and afternoon productivity after shifting away from high-II breakfast and lunch options.

Important Note

Always work with your healthcare provider before making significant dietary changes, especially if you have diabetes, take insulin or glucose-lowering medications, or have a history of disordered eating. Lowering dietary insulin stimulus while on insulin medication without medical supervision can cause hypoglycemia.

Frequently Asked Questions

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

Not exactly. While ketogenic and low-carb diets often produce low insulin responses, they are defined by macronutrient targets rather than insulin response per se. A low-II diet can include moderate amounts of legumes, root vegetables, and whole grains — foods that would be restricted on strict low-carb plans — if their insulin index scores are sufficiently low. Conversely, a high-protein, low-carb diet can still include many medium-to-high-II foods like dairy and whey. The insulin index is a more direct and nuanced measurement than carbohydrate content alone.

Do I need to track every food's insulin index score daily? +

No — and obsessive tracking can be counterproductive. The most practical approach is to build a mental map of food categories: fatty fish, whole eggs, most non-starchy vegetables, nuts, seeds, olive oil, and lean unprocessed meats are reliably low-II. Refined grains, sugary foods, dairy-protein products, and ultra-processed items are reliably high-II. Learning the patterns for your most frequently eaten foods is usually sufficient for meaningful dietary improvement.

Will eating low-II foods cause me to lose muscle mass? +

No — not if protein intake is adequate. Insulin has anabolic effects on muscle, but studies show that consuming sufficient protein (typically 1.6–2.2g per kg of body weight per day) supports muscle protein synthesis even at lower overall insulin levels. In fact, strategic protein intake from lower-II sources like eggs, chicken, and fish can support lean mass preservation while simultaneously reducing insulin-driven fat storage. Timed protein intake around resistance training maintains muscle synthesis independently of insulin spikes.

Does cooking method affect the insulin index of a food? +

Yes, meaningfully so in some cases. Cooking increases the bioavailability of starches, raising both glycemic and insulin responses. For example, al dente pasta has a lower insulin response than well-cooked pasta. Cooling and reheating starchy foods (e.g., potatoes, rice) increases their resistant starch content, lowering the II. Adding fat, fiber, or acidic ingredients like vinegar to a meal also blunts the insulin response of carbohydrate-containing components, a phenomenon called the "food matrix effect."

How long does it take to see benefits from shifting to a low-II diet? +

Subjective improvements — steadier energy, fewer cravings, better sleep — are often reported within 1 to 2 weeks. Measurable metabolic improvements in fasting insulin, triglycerides, and HbA1c typically appear within 4 to 8 weeks in dietary intervention trials. More structural changes like improved insulin sensitivity and body composition changes usually require a sustained 12-to-24-week commitment. The response varies substantially based on an individual's metabolic health baseline.

Is there a database where I can look up the insulin index of specific foods? +

Yes — the InsulinGuru Food Database contains insulin index values for over 250 foods, sourced from peer-reviewed research and continuously updated as new data becomes available. You can search by food name, filter by category, and sort by II score. Unlike glycemic index databases, dedicated insulin index databases are rare, which is why we built ours to be as comprehensive as possible.

The Bottom Line

The insulin index is one of the most clinically meaningful — yet underutilized — tools in nutrition science. While calorie counting and glycemic index remain useful frameworks, the insulin index adds a crucial dimension: it tells you how intensely your body's primary fat-storage hormone will respond to what you eat.

A diet built around low-II foods — eggs, fatty fish, leafy vegetables, nuts, olive oil, and lean meats — produces a hormonal environment favorable to fat oxidation, stable energy, improved satiety, and better long-term metabolic health. These are not exotic or difficult foods. They are the foundation of many traditional diets that have sustained human health for millennia.

You don't need to eat perfectly or track every score. The goal is to shift the average insulin stimulus of your diet progressively lower — and to understand why certain foods that appear healthy by other metrics may still be undermining your metabolic goals.

Next Steps

Explore the InsulinGuru Food Database → to check the insulin index of your most-eaten foods, or read our deep-dive on Low-II Meal Planning for Beginners →

References & Further Reading

Holt SHA, Miller JC, Petocz P. An insulin index of foods: the insulin demand generated by 1000-kJ portions of common foods. American Journal of Clinical Nutrition. 1997;66(5):1264–1276.
Bell KJ, Saad S, Tillett BJ, et al. Macronutrient adaptations to dietary changes in insulin secretion and resistance. Diabetologia. 2015;58(3):443–452.
Ludwig DS, Ebbeling CB. The carbohydrate-insulin model of obesity: beyond calories in, calories out. JAMA Internal Medicine. 2018;178(8):1098–1103.
Ebbeling CB, Feldman HA, Klein GL, et al. Effects of a low carbohydrate diet on energy expenditure during weight loss maintenance. BMJ. 2018;363:k4583.
Feinman RD, Pogozelski WK, Astrup A, et al. Dietary carbohydrate restriction as the first approach in diabetes management. Nutrition. 2015;31(1):1–13.
Azzeh FS, Header EA. Insulin response to macronutrient composition. Pakistan Journal of Nutrition. 2012.
Unwin DJ, Tobin SD, Murray SW, et al. Substantial and sustained improvements in blood pressure, weight and lipid profiles from a carbohydrate restricted diet. International Journal of Environmental Research and Public Health. 2019;16(15):2680.