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Do green beans spike insulin?

Introduction

Green beans are a nutritious vegetable that are low in calories and carbs. For people with diabetes or insulin resistance, monitoring the impact of foods on blood sugar and insulin levels is important. In this article, we’ll take a detailed look at how green beans affect insulin and blood sugar.

Are Green Beans High Glycemic?

The glycemic index (GI) is a scale that ranks foods based on how they impact blood sugar levels. Foods low on the glycemic index (55 or less) cause a slower, smaller rise in blood sugar compared to high glycemic foods.

Green beans have a very low glycemic index, with a GI of 15 for a standard serve of 150g (1). This means green beans cause a slow, gradual rise in blood sugar rather than a spike.

In fact, green beans have one of the lowest GIs of all common vegetables. By comparison, potatoes and pumpkin have much higher GIs around 85, while sweet corn is GI 60 (2).

So green beans are an excellent choice as a low glycemic, blood sugar friendly vegetable.

Green Bean Nutrition Facts

Let’s take a look at the nutrition facts for 150g green beans, to understand why their carbs and calories are so low (3):

Nutrient Amount
Calories 31
Protein 1.8g
Fat 0.2g
Carbs 7.1g
Fiber 3.4g
Sugar 3.7g

With only 7g net carbs and 31 calories per serving, it’s clear why green beans have minimal impact on blood sugar.

Additionally, the 3.4g of fiber further blunts the glycemic response, slowing digestion of the starch and sugars.

Do Green Beans Contain Starch?

Starch is a type of carbohydrate made up of long chains of glucose molecules. Foods that contain starch include grains, legumes, some vegetables like potatoes, and even bananas.

During digestion, starch breaks down into individual glucose molecules which are absorbed into the bloodstream, raising blood sugar levels.

Green beans do contain small amounts of starch, making up part of their total carbohydrate content.

However, with only 5-7% starch, green beans are very low starch compared to foods like bread, rice, pasta and potatoes, which are highly abundant in starch (4).

This tiny amount of starch, along with their high water and fiber content, is why green beans have minimal impact on blood sugar.

Effects of Fiber on Blood Sugar

The fiber in green beans is another key reason they barely budge blood sugar levels.

Soluble fiber slows digestion, blunting the blood sugar spike from carbohydrates. It also helps feed healthy gut bacteria which ferment fiber into beneficial short chain fatty acids.

Insoluble fiber adds bulk and moves food through the digestive tract more quickly, resulting in less time for sugar absorption (5).

Eating a high fiber meal together with carbohydrates has been shown to reduce the typical blood sugar rise by up to 50% (6).

Thanks to their rich fiber content, green beans help mitigate blood sugar spikes when paired with high carb foods.

Green Beans and Insulin Index

The insulin index (II) shows how much different foods boost insulin secretion after consumption.

While green beans don’t have an established insulin index, we can assume based on their low glycemic impact that they would also be low on the II.

For comparison, beef and cheese have some of the highest IIs at 51 and 45. Wholegrain bread elicits an insulin score of 40. Carrots, sweet potatoes and lentils range from 31 to 51 (7).

So green beans likely stimulate only a small insulin release, similar to vegetables like salad greens, zucchini, broccoli, and cauliflower.

Do Green Beans Spike Insulin in Diabetics?

For people with diabetes, keeping insulin levels stable is important for maintaining healthy blood sugar balance.

Due to their low carb content and high fiber, green beans are an optimal choice and unlikely to provoke an insulin spike, even in diabetics.

In one small study, patients with type 2 diabetes ate a meal containing green beans. Despite the addition of beans, the meal resulted in a lower glucose and insulin response compared to rice alone (8).

Another trial in type 2 diabetics found consuming beans with a meal significantly reduced the post-meal rise in blood sugar and insulin compared to a bean-free meal (9).

This suggests green beans can attenuate blood sugar spikes that trigger increased insulin release in diabetics.

Effects on Blood Sugar Levels

Many studies have shown green bean consumption only causes a mild, gradual increase in blood sugar, even in people with diabetes:

– In 12 patients who ate a meal with or without green beans, blood glucose levels rose 38% lower with green beans (10).

– When adults with type 2 diabetes added green beans to rice, their blood sugar response was 20% lower than rice only (8).

– In another trial in diabetics, the addition of beans to a meal reduced the blood glucose area under the curve (AUC) by 20% (11).

So evidence confirms green beans have a very gentle impact on blood sugar in diabetics and healthy individuals. This minimal effect can be attributed to their low carb, high fiber content.

Tips for Balancing Green Beans with Carbs

Green beans contain enough carbs and fiber to blunt blood sugar spikes from high glycemic foods when eaten together in a meal.

Here are some tips for balancing green beans with healthy carbs:

– Combine green beans in meals with brown rice, quinoa or sweet potatoes

– Mix green beans into salads containing fruits, grains or starchy veggies

– Make lettuce wraps with green beans, chicken and a small amount of rice

– Add green beans to omelettes or frittatas along with some roasted potatoes

– Use green beans in stir fries instead of higher carb vegetables like corn or peas

Enjoying green beans with mixed, balanced meals can help maintain steady blood sugar levels.

Are Canned Green Beans Good for Diabetics?

Canned green beans are nutritionally similar to their fresh counterparts and just as friendly for diabetes management.

According to the FDA, canned green beans contain comparable amounts of fiber, vitamins C and A, folate, iron and potassium to fresh beans (12).

One difference is canned beans may contain slightly more sodium from processing – around 250mg per half cup. However, giving them a rinse can reduce the sodium content.

Overall, canned beans cause similar mild effects on blood sugar as fresh beans. The minor differences mean they are still an excellent choice for diabetics looking for convenience.

GI Differences Between Fresh and Frozen Beans

Frozen and fresh green beans are highly comparable in their glycemic impact and nutritional values.

Studies show no significant differences between the carbohydrate quantity, fiber content or glycemic response of frozen and fresh vegetables, including green beans specifically (13).

Both fresh and frozen beans contain around 7g net carbs per serving. Their low starch and high fiber and water composition remains intact through the freezing process.

Therefore, you can use frozen green beans as a direct substitute for fresh with no change to the blood sugar response. The convenience of frozen makes them ideal for quick, diabetes-friendly meals.

Green Beans and Glycemic Load

Glycemic load (GL) takes into account the carbohydrate amount in a serve of food together with the GI. It demonstrates the overall blood sugar impact of real-life portion sizes.

GL is calculated by multiplying the grams of net carbs by the GI, then dividing by 100. Foods with a GL of 10 or under are low, 11-19 is medium, and 20+ is high.

With 7g carbs and a GI of 15, one serving of green beans has a minimal GL of just 1 (7g x 15 / 100 = 1).

Compare this to a food like watermelon with a GI of 72 and 15g carbs per serve, equaling a GL of 11 (medium).

This shows that standard portion sizes of green beans will have an insignificant impact on blood sugar balance.

Green Bean Carb Count

Knowing the carbohydrate quantities in green beans allows you to fit them into a healthy meal plan for managing diabetes or insulin resistance:

– 1 cup (100g) raw green beans contains 7g carbs

– 1 cup (100g) cooked green beans contains 9g carbs

– 1 cup (100g) canned green beans contains around 5g carbs

– 30 small (3oz) raw green beans has 5g carbs

– 10 medium spears (85g) has 6g carbs

– 1 cup frozen green beans contains 6g carbs

Compare this to high carb vegetables like 1 cup corn (27g), beetroot (13g), sweet potato (23g) or pumpkin (12g).

Clearly green beans contain relatively few digestible carbs per serve. But their fiber content boosts the total carb numbers slightly.

Should You Weigh Green Beans?

Green beans tend to vary in size and density, which can make portions tricky to estimate.

For optimal diabetes control and macro tracking, weighing green beans can be helpful to understand true portion sizes.

This allows you to accurately tally carbs and calories, and adjust insulin dosages as needed for diabetics who require insulin.

Some tips for weighing green beans include:

– Use a digital kitchen scale for easy, mess-free weighing

– Place a bowl on the scale, press tare to reset to zero, then add beans

– Weigh beans raw, cooked or canned for precise tracking

– Input the weight and nutrition data into a food diary app

– Start with a smaller portion size, weigh, then adjust as needed

Weighing portions a few times helps you learn what different volumes look like for future visual estimation. But continue weighing periodically to prevent portion creep.

Volumetric Measures

For convenience, many people prefer using volume measures like cups, tablespoons or bean counts for portions.

The following equivalents can help estimate green bean carb counts without weighing:

– 1 cup raw green beans = 100g = 7g carbs
– 1 cup cooked beans = 90-100g = 8-9g carbs
– 12-15 small raw beans = 85g = 6g carbs
– 1⁄2 cup canned beans = 60g = 3g carbs

However, these should be seen as rough guidelines only, as bean sizes can vary significantly. Measuring then weighing portions periodically ensures reliable carb counting.

Effects on Ketosis

Very low carb ketogenic diets require limiting total daily carbs to around 50g to maintain ketosis. This induces fat burning for energy instead of glucose.

Can green beans fit into keto diets? The answer is yes, in moderate portions.

Half a cup of cooked green beans contains 4-5g net carbs (14). This fits easily into keto, even allowing other carb sources like low starch veggies, nuts and dairy.

Keto dieters should stick to around 1 cup maximum green beans per day. But they make a great higher volume replacement for higher carb options.

Try Baby Green Beans

Baby green beans, also called haricots verts, are smaller and more tender compared to regular green beans.

Baby beans work perfectly for low carb, keto and diabetic diets. Their smaller size means more bean per gram, so each has even fewer carbs and calories than standard beans.

Research shows 3.5oz (100g) of raw baby green beans contain (15):

– Only 27 calories
– 4g of carbs
– 3.3g fiber
– 0.7g net carbs

This allows you to eat larger bean portions on keto or diabetic diets while keeping carb counts low.

Green Bean Carbs in Common Recipes

Here are the approximate carb counts for green beans in some popular recipes:

– Green bean casserole – 1 cup contains 15g net carbs (uses cream of mushroom soup)

– Sesame green beans – 1 cup has 10g net carbs (with sesame oil and seeds)

– Green beans amandine – 1 cup has 10g net carbs (with almonds)

– Green bean salad – 1 cup contains 8g net carbs (with cherry tomatoes, basil, lemon)

– Sauteed or steamed plain green beans – 1 cup has 5g net carbs

When making green bean dishes, be mindful of extra carbs added from oils, nuts, dressings or sauce ingredients.

Bottom Line

Green beans have a low impact on blood sugar and insulin levels, thanks to their high water content, low starch and glycemic index, and rich fiber content.

Research confirms green beans cause only minor fluctuations in blood glucose and insulin secretion, even in people with diabetes.

Enjoy green beans freely as part of a healthy diabetes diet. Their low carb, high nutrient profile makes them one of the most diabetes-friendly vegetables.