Low-Insulin Foods: Weight Impact Score of 23 Popular Foods

Calorie totals describe energy content. They say nothing about whether a food is likely to keep your blood sugar steady or send it soaring and call in a lot of insulin. The Weight Impact Score estimates the latter. The best-known evidence that equal calories can mean very different insulin responses is the insulin index study: Holt and colleagues fed 240 kcal portions of 38 foods to groups of 11 to 13 healthy volunteers and measured insulin responses, against 100 for white bread, of 121 for boiled potatoes, 92 for chocolate chip cookies, 79 for white rice and 31 for eggs (Holt et al., 1997). A 2024 compilation now lists insulin index values for 629 foods and drinks from 80 studies (Hendricks et al., 2024).

We scored 23 common household foods on the 1 to 10 scale, each at the serving the RealFoods app shows for it. Each score is for one food eaten on its own; further down, we show what the research says happens when protein, fat, fibre or nuts share the plate. The list below is sorted from the lowest estimated impact to the highest. For the meal where most days begin, see our scored list of low insulin breakfast foods.

We argue this ranking is more actionable than a calorie list, because the swap it points to is concrete: the high scorers here are mostly refined starch or sugar, and the low scorers are foods built on protein, fat and fibre. Most of the lowest-scoring foods are minimally processed, the kind covered in our guide to what counts as real food.

Which foods have a low Weight Impact Score?

11 of the 23 foods score 1 to 2, the Burning Fat zone: almonds, cheese, chicken breast, eggs, salmon, steak and walnuts (all 1) and broccoli, carrots, milk and strawberries (all 2). The table lists all 23 foods at the serving the RealFoods app shows for each, lowest score first.

Almonds

1/10 • Burning Fatper 30 g serving

Fibre, fat and protein with few digestible carbs, so a 30 g handful has very little estimated impact on blood sugar.

Cheese

1/10 • Burning Fatper 30 g serving

High in fat and protein with almost no carbohydrate, so a 30 g serving has a low estimated insulin impact.

Chicken Breast

1/10 • Burning Fatper 170 g serving

A pure protein source. Negligible estimated insulin impact, which makes it an easy anchor for a low-impact meal.

Eggs

1/10 • Burning Fatper 100 g serving

Rich in protein and fat. Little carbohydrate, so little effect on blood sugar, and very filling.

Salmon

1/10 • Burning Fatper 170 g serving

Packed with omega-3s and high-quality protein, with no carbohydrate to raise blood sugar.

Steak

1/10 • Burning Fatper 220 g serving

No carbohydrate, so even a large 220 g steak scores 1. Highly satiating.

Walnuts

1/10 • Burning Fatper 30 g serving

Rich in omega-3 fats and fibre. A slow-digesting food with little effect on blood sugar.

Broccoli

2/10 • Burning Fatper 150 g serving

Fibrous and filling. Much of its small carbohydrate load is fibre, so even a generous 150 g serving scores low.

Carrots

2/10 • Burning Fatper 130 g serving

Sweet, but mostly water and fibre, so a 130 g serving stays in the Burning Fat zone.

Milk

2/10 • Burning Fatper 240 g serving

Contains natural sugar (lactose), but a 240 g glass is a modest amount, so it stays in the Burning Fat zone.

Strawberries

2/10 • Burning Fatper 150 g serving

A surprisingly low-impact fruit. High water and fibre content keeps the natural sugars a small load.

Blueberries

3/10 • Mostly Neutralper 150 g serving

Denser in sugar than strawberries, but the fibre in the whole berry keeps a 150 g serving in the Mostly Neutral zone.

Watermelon

4/10 • Mostly Neutralper 280 g serving

Mostly water, so even a large 280 g serving adds up to only about 21 g of carbohydrate, which keeps it in the Mostly Neutral zone.

Bananas

5/10 • Fat-Burning Pausedper 120 g serving

A starchy fruit. A 120 g banana carries about 28 g of carbohydrate, which puts it mid-scale.

White Bread

6/10 • Fat-Burning Pausedper 60 g serving

Refined flour that digests quickly. A 60 g serving lands mid-scale, and bigger servings score higher.

Burger

6/10 • Fat-Burning Pausedper 220 g serving

The refined bun carries most of the load, so a 220 g burger lands in the Fat-Burning Paused zone.

Potatoes

6/10 • Fat-Burning Pausedper 210 g serving

A dense starch: a 210 g serving carries about 44 g of carbohydrate, which lands in the Fat-Burning Paused zone.

Pizza

7/10 • Keeping Fatper 230 g serving

A refined flour crust in a large 230 g serving, about 76 g of carbohydrate, pushes pizza into the Keeping Fat zone.

Pasta

7/10 • Keeping Fatper 200 g serving

A 200 g home plate of cooked pasta, about 70 g dry, is refined starch: about 62 g of carbohydrate, so it lands in the Keeping Fat zone.

French Fries

8/10 • Keeping Fatper 120 g serving

Refined potato starch, deep-fried in oil. A 120 g serving lands in the Keeping Fat zone.

White Rice

8/10 • Keeping Fatper 175 g serving

Milled white rice is fast-digesting starch with almost no fibre. A 175 g serving carries about 49 g of carbohydrate, which puts it in the Keeping Fat zone.

Orange Juice

9/10 • Keeping Fatper 300 g serving

Stripped of the fruit's fibre, a large 300 g glass (about 290 ml) delivers about 31 g of carbohydrate, mostly sugar, very quickly, which puts it in the Keeping Fat zone.

Cookies

10/10 • Keeping Fatper 120 g serving

Refined flour and sugar with fat. A 120 g serving, about 2 to 3 large bakery cookies, carries about 71 g of carbohydrate, which puts it at the top of the scale in the Keeping Fat zone.

Does eating these foods together change the response?

Yes, which is why the RealFoods app scores whole meals, not single foods. The evidence comes from short, controlled feeding studies, most of them small and covering a single meal, so read them as patterns rather than promises. Their results are fairly consistent for blood sugar and mixed for insulin.

• Protein lowers the blood sugar rise but adds insulin. A 2024 meta-analysis of 154 feeding comparisons found that adding protein to a carbohydrate meal lowered the blood sugar response and raised the insulin response, with a smaller blood sugar effect in type 2 diabetes (Wolever et al., 2024). In 12 healthy adults, white rice eaten with chicken, oil and a leafy vegetable had a glycemic index of 50, against 96 for rice alone (Sun et al., 2014). The protein source matters: in 15 healthy men, only tofu lowered the blood sugar response to rice, while fish and egg white raised insulin without lowering blood sugar (Quek et al., 2016). Protein also calls in glucagon, the hormone that counterbalances insulin: in that rice trial, glucagon rose when fish or tofu were added and fell below baseline with rice alone (Quek et al., 2016).
• Fat slows the rise in some people, not all. In 10 healthy men, butter eaten with potato lowered the blood sugar response by about 40% and slightly raised insulin (Gannon et al., 1993). In 7 men with type 2 diabetes, the same addition did not lower blood sugar (Gannon et al., 1993).
• Nuts lowered both numbers in several trials. 20 g of almonds eaten 30 minutes before a sugar drink lowered blood sugar and insulin in 60 Asian Indian adults with prediabetes (Gulati et al., 2023, funded by the Almond Board of California). A breakfast built on walnuts produced a lower insulin response at two hours than a nut-free meal in 28 adults with overweight or obesity (Rock et al., 2017, funded in part by the California Walnut Commission).
• Fibre and legumes soften the blood sugar rise. Breakfasts with about 5 g of soluble fibre lowered the blood sugar rise in 19 adults with type 2 diabetes, with no difference in insulin (de Carvalho et al., 2017). Hummus on its own produced much smaller blood sugar and insulin responses than the same carbohydrate from white bread (Augustin et al., 2016, funded by Sabra).

Protein foods are not insulin-free either: in the insulin index study, beef and white fish produced insulin responses of 51 and 59 against 100 for white bread, well above their blood sugar responses (Holt et al., 1997). The WI Score is one modelled estimate that has not been validated against measured insulin; how the Weight Impact Score works explains what it can and cannot tell you.

Ready to stop guessing what to eat?

Common questions

What is a Weight Impact Score?

Weight Impact is RealFoods' 1 to 10 score for how strongly a meal is likely to raise blood sugar and call in insulin, where lower is better: 1 to 2 is Burning Fat, 3 to 4 Mostly Neutral, 5 to 6 Fat-Burning Paused and 7 to 10 Keeping Fat. It is a modelled estimate from the meal's foods, not a medical measurement.

Which foods have a low Weight Impact Score?

At the serving the RealFoods app shows, RealFoods estimates a Burning Fat Weight Impact Score (1 to 2) for almonds, cheese, chicken breast, eggs, salmon, steak and walnuts (all 1) and broccoli, carrots, milk and strawberries (all 2).

What food has the lowest Weight Impact Score?

Protein and fat foods with almost no carbohydrate score lowest. Almonds and cheese (30 g), chicken breast (170 g), eggs (100 g), salmon (170 g), steak (220 g) and walnuts (30 g) all score 1 out of 10 at the serving shown.

What food has the highest Weight Impact Score?

Of these 23 foods, cookies (120 g) score 10, and orange juice (300 g) scores 9. Large servings of fast-digesting starch or sugar score highest.

Does portion size change the Weight Impact Score?

Yes. Each score belongs to the serving it was calculated for. In the RealFoods app, cookies score 6 at 45 g, 9 at 100 g and 10 at 120 g, and pasta scores 6 at 140 g, 7 at 200 g and 8 at 280 g, so starchy and sugary foods climb as the portion grows. Protein foods stay low: chicken breast, salmon and steak score 1 even at 170 g to 220 g.

Is granola bad for your blood sugar?

Most commercial granola is mostly fast-digesting starch and sugar: it is toasted oats bound with honey or syrup and dried fruit, and RealFoods scores half a cup (55 g) of sweetened commercial granola or muesli 6 out of 10, in the Fat-Burning Paused zone (a modelled estimate). A smaller portion scores lower, and individual responses vary. See the full list of foods that cause weight gain.