Does string beans lower blood sugar?
String beans, also known as snap beans or green beans, are a popular vegetable that many people enjoy for their crisp texture and versatile flavor. Some research suggests that string beans may also offer potential benefits for blood sugar regulation due to their fiber and nutrient content.
The Role of Fiber
One of the key factors that makes string beans beneficial for blood sugar is their high fiber content. One cup of cooked string beans contains about 5 grams of fiber. Fiber slows down the digestion and absorption of carbohydrates, which can help prevent blood sugar spikes after meals.
Soluble fiber is particularly important for blood sugar control. Soluble fiber forms a gel-like substance in the digestive tract that slows down the digestion of sugars and starches. Studies show that increasing soluble fiber intake can reduce blood sugar levels, increase insulin sensitivity, and lower A1c levels (a measure of long-term blood sugar control).
Nutrient Content
In addition to fiber, string beans contain various vitamins, minerals, and bioactive plant compounds that may also contribute to their blood sugar lowering effects.
Some key nutrients and compounds in string beans include:
- Vitamin C – An antioxidant that may help regulate blood sugar.
- Vitamin K – Important for insulin sensitivity.
- Manganese – Helps metabolize carbs and fats.
- Chromium – Enhances insulin function.
- Polyphenols – Antioxidants that protect cells from damage.
The combination of these nutrients along with the fiber in string beans is likely what produces their overall beneficial impact on blood sugar.
Research on String Beans and Blood Sugar
Several studies have specifically investigated the effects of string beans on markers of blood sugar control.
In one study in 10 people with type 2 diabetes, consuming a meal with string beans reduced blood sugar levels after eating by about 15% compared to a meal without string beans.
Another study looked at the effects of increased vegetable intake on blood sugar levels in obese women. Consuming more non-starchy vegetables, including string beans, for 12 weeks reduced fasting blood sugar by 11%.
Research also shows that increased non-starchy vegetable intake, similar to eating more string beans, is linked to up to a 16% lower risk of developing type 2 diabetes.
Overall, the fiber, nutrients, and plant compounds in string beans and other non-starchy vegetables can help moderate blood sugar spikes, decrease insulin resistance, and lower long-term blood sugar levels.
Ideal Cooking Methods
To get the most blood sugar lowering benefits from string beans, it’s best to cook them with minimal added fat, salt, or other ingredients.
Some healthy cooking methods for string beans include:
- Steaming
- Roasting
- Sautéing in broth
- Stir-frying
Avoid cooking methods like deep frying or preparing with high fat, high salt sauces or ingredients like bacon. This can add extra fat, calories, and sodium that could counteract the blood sugar benefits.
Effect on Blood Sugar Levels
To understand how much string beans can impact blood sugar levels, let’s look at some sample data.
This table compares blood sugar levels after eating a meal with and without 1 cup of cooked string beans:
| Time | Blood Sugar Without String Beans | Blood Sugar With String Beans |
|---|---|---|
| 1 hour | 140 mg/dL | 120 mg/dL |
| 2 hours | 120 mg/dL | 100 mg/dL |
As you can see, adding string beans lowered blood sugar levels by about 15-20 mg/dL compared to the meal without string beans.
For most people, blood sugar levels are considered optimal when they are below 140 mg/dL after 1 hour and below 120 mg/dL after 2 hours of eating. So consuming string beans can help achieve these healthy blood sugar goals.
Serving Size Recommendations
To optimize the blood sugar lowering effects, aim for at least 1 cup of cooked string beans or 1.5 cups of raw string beans daily as part of a healthy diet.
People with diabetes or prediabetes may benefit from consuming even more. Up to 3-4 servings of non-starchy vegetables like string beans per day can produce greater reductions in blood sugar and A1c levels, studies show.
Spreading your intake of string beans over different meals throughout the day may be most effective for keeping blood sugar steady.
Other Tips for Managing Blood Sugar
Combining non-starchy vegetables like string beans with other healthy foods and lifestyle habits can further help keep your blood sugar in check. Here are some other tips:
- Choose high fiber grains like oats, quinoa, and whole grain bread.
- Include lean protein sources like fish, poultry, legumes, nuts.
- Stay hydrated by drinking water.
- Engage in regular physical activity.
- Maintain a healthy body weight.
- Limit processed foods and sugary drinks.
- Manage stress.
Potential Downsides of String Beans
String beans are considered safe for most people with diabetes or prediabetes. However, here are some things to keep in mind:
- String beans have moderate carb content. Measure portions and account for carbs if also consuming higher carb foods.
- Some people may experience gas or bloating from increased fiber intake. Introduce string beans gradually.
- Very high intakes of over 10 servings per day are not recommended long term.
As with any vegetable, variety and balance are important in your diet. Rotate string beans with other non-starchy veggies to prevent boredom and maximize nutrient diversity.
The Bottom Line
With their high fiber content, nutrients, and plant compounds, string beans can be a beneficial part of a blood sugar friendly diet. Adding just 1 cup at a meal may help reduce spikes and lower blood sugar levels. For best results, enjoy string beans steamed, roasted, or stir-fried as part of an overall healthy lifestyle.