Glycemic Index and Health Benefits of Fresh Green Soybeans

Understanding the Glycemic Index and Health Benefits of Edamame

Edamame, or fresh green soybeans, have become a popular snack and addition to salads and stir-fries. But many people wonder about the glycemic index and health effects of this vegetable. Is edamame good or bad for blood sugar and your overall health?

What is the Glycemic Index?

The glycemic index (GI) measures how quickly foods raise blood glucose levels. Foods are ranked based on how they compare to the absorption of pure glucose. The higher the GI, the faster the food causes spikes in blood sugar.

Low GI foods, with scores under 55, are digested more slowly and help control appetite and energy levels. High GI foods over 70 can lead to crashes and cravings soon after eating. Moderately high GI foods score between 56-69.

The Glycemic Index of Edamame

So where does edamame fall on the GI scale? Plain, unsalted edamame has a GI of 18, making it an extremely low glycemic food. This means the carbohydrates in edamame are broken down slowly, preventing surges in blood glucose.

In fact, edamame contains complex carbs and ample fiber. This helps explain its low ranking, as fiber slows digestion. The protein and healthy fats in edamame also help stabilize blood sugar response.

The Nutrition and Health Benefits of Edamame

Beyond having a favorable glycemic impact, edamame offers several other nutritional and health advantages. Getting to know the complete nutrition profile of edamame helps clarify all this superfood has to offer.

Edamame Nutrition Facts

One cup of frozen, shelled edamame contains:

• Calories: 189
• Protein: 17 grams
• Fat: 8 grams
• Fiber: 8 grams
• Carbs: 16 grams
• Calcium: 102 mg
• Iron: 15% Daily Value
• Vitamin C: 12% DV
• Vitamin A: 10% DV

Edamame is high in vitamins, minerals, antioxidants and omega-3 fatty acids. It contains all 9 essential amino acids needed to form complete protein. In particular, it is rich in an amino acid called arginine.

Arginine and Nitric Oxide Production

The generous arginine content helps make edamame supportive for heart health. Arginine converts to nitric oxide in the body. Nitric oxide relaxes and expands blood vessels, increasing blood flow.

This reduction in blood pressure lowers cardiovascular disease risk. Nitric oxide also discourages plaque deposits inside artery walls through its anti-inflammatory actions.

Cholesterol Lowering Abilities

Clinical research highlights edamames cholesterol lowering effects. Regularly eating edamame significantly decreases LDL bad cholesterol. This also lowers total cholesterol levels.

These heart protective benefits come from edamames supply of plant sterols. The steroid compounds block cholesterol absorption in the intestines. With less circulating cholesterol, less deposits up as plaque in blood vessels.

Anti-Cancer Effects

The antioxidant content of edamame assists in cancer protection as well. Edamame is rich in compounds like phenolic acids, flavonoids and isoflavones. These eliminate free radicals that can lead to DNA mutation and tumor growth.

Population studies associate frequent edamame intake with up to 60% lower cancer risk. The anti-inflammatory nature of edamame is also believed to inhibit cancer cell metastases.

Comparing Edamame and Soy Beans

Edamame buds directly from the soy plant before the beans harden in their pods. Soybeans are simply harvested later, once the bean pods mature and dry out in the field.

But does the difference in harvest timing alter nutritional value? Fresh edamame and dried soybeans share similar health benefits, though some variation exists in their nutrition profile.

Nutrition Comparison

In their whole food forms, one cup shelled edamame contains:

• 8 grams protein
• 8 grams fiber
• 5 grams fat

One cup boiled mature soybeans has:

• 14 grams protein
• 10 grams fiber
• 15 grams fat

While soybeans offer higher amounts of protein and fiber, the gap largely disappears once edamame is served in the pod. The nutrition packed bean pods provide comparable protein, fat and minerals to soybean servings.

Glycemic Response

Interestingly, the glycemic index does seem to differ between fresh and mature legumes. Edamame has an extremely low GI of just 18 as previously mentioned.

Boiled soybeans, on the other hand, have a moderately high GI of 71. This indicates the additional maturation process impacts carbohydrate metabolism. Still, soybeans have a lower GI than many other beans.

Isoflavone Content

Another variation between edamame and soybeans is their isoflavone content. These compounds are linked to anti-cancer, heart healthy and antioxidant activity.

Some research found immature edamame contains lower total isoflavone levels compared to mature soybeans. However other studies show significantly higher genistein content, one of the most potent isoflavones, in edamame.

More research on the differing phytonutrient profiles is still needed. But both edamame and soybeans are considered nutritious functional foods.

How to Buy and Store Fresh Edamame

Seeking out high quality, fresh edamame is important to fully utilize its nutritional benefits. Follow this edamame buying and storage guide for best quality.

Checking Bean Maturity

When buying edamame pods, look for a bright, even green color. Avoid yellowing pods or those with brown spots, which signal over-ripeness. Beans should completely fill out pods.

Pods that feel limp or lightweight often contain shriveled beans lacking adequate moisture. Pick pods that feel rigid and heavy for high bean content.

Inspecting Interior White Fuzz

Next examine pod interiors for a key freshness indicator. Carefully crack open one end. Inside you should see a thin, bright white fuzz coating around the beans.

As edamame ages and dries out after harvest, it loses this inner fuzz. Absence of fuzzy lanugo suggests beans are older. The fuzz helps lock in moisture and flavor.

Storing Edamame Properly at Home

To extend shelf life after buying fresh edamame, promptly refrigerate pods. Keep them loosely packed in a perforated plastic bag in your crisper drawer. This allows airflow to prevent excess moisture buildup.

You can also shell beans and freeze for long term storage. Blanch pods first for 2-3 minutes, shock in ice water, then pop out beans and freeze in an airtight container for 4-6 months.

How to Cook Edamame for Maximum Nutrition

To unlock the full nutritional bounty of edamame, proper cooking methods matter. Here are some easy preparation tips.

Should You Boil or Steam?

Experts recommend steam cooking over boiling to maximize nutrition. Water soluble vitamins like C and B vitamins leach out easily when boiling veggies. Steaming better preserves these.

If boiling, use minimal water and avoid overcooking. Cook just until beans become bright green and tender, about 5 minutes. Quick steaming takes under 4 minutes.

To Salt or Not to Salt?

Salting edamame is popular for added flavor, but it impacts health effects. Consuming edamame with no salt maximizes the low glycemic benefits.

Added salt can elevate the GI somewhat, as salt alters glucose absorption rates. However, the glycemic index change is fairly small. Lightly salting doesnt diminish the weight loss and cholesterol lowering advantages.

What About Reheating?

Precooked, frozen pods and beans certainly offer convenience. But some nutrients do degrade with reheating compared to freshly prepared. Catechin levels fall by 15% and vitamin C drops by 14% on average when reheating.

If reheating precooked edamame, use the microwave or steamer rather than skillet sauting. Limit exposure to excess heat by reheating only small portions as needed just before serving.

Disclaimer: This article is for informational purposes only and does not constitute medical advice. Always consult with a healthcare professional before starting any new treatment regimen.