Corn Glycemic Index: Health Benefits

Corn, also known as maize, has been a staple crop in North American agriculture for hundreds of years. It is drought resistant, easy to grow, and versatile in cooking. The main variety we consume is sweet corn, which offers a range of nutrients and fiber. 

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Americans consume the largest amount of corn and corn by-products in the world.¹ In 2019, it was estimated that each person consumed 36.5 lbs of corn products yearly. This is a significant increase from data thirty years ago, documenting approximately 21 lbs consumed per person. 

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This article will explore how corn may impact blood sugar levels and the health benefits that could be gained from including this vegetable in meals. 

Corn contains natural carbohydrates, which are broken down into simple sugars during digestion. Sugars from food are absorbed into your bloodstream and can raise your blood sugar levels. 

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Corn alone may not cause your blood sugars to spike, as it is considered a low glycemic index food, but when you consider the full glycemic load of your meal, there is a good chance you may see a spike. It is common to serve corn alongside other high-starch and high-carb foods, which all accumulate and can raise blood sugar levels. 

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Every person will have a unique glycemic response to corn. Some people may experience higher blood glucose levels, and others may not. The below glycemic index and glycemic load data are based on a serving size of 100g (approximately one medium cob) of sweet, yellow, raw corn.² ³

Corn is a robust source of energy, vitamins, minerals, and fiber while low in sodium and fat. While there are natural sugars in corn, positive nutritional properties make it a safe option to include in meals. 

Unprocessed versions of corn can be part of your weight loss journey. The bright, juicy kernels are high in fiber and have a variety of minerals and vitamins. 

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What you pair corn with will significantly influence its nutritional value. Try to pair corn with fresh, non-starchy vegetables, spices, and lean proteins.

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You will want to avoid processed foods containing corn, which could hinder your weight loss. These foods often have a higher glycemic index than raw corn, including corn chips, corn tortillas, high-fructose corn syrup, and corn starch.

Corn, a low glycemic index food on its own, is safe for people living with diabetes. When included in processed foods, the glycemic index of corn can be significantly raised, so individuals should be mindful of portion sizes. 

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The American Diabetes Association classifies corn as one of the best starchy vegetables to choose from when planning meals. However, this vegetable should make up only a quarter of your plate.⁹ You can balance this starchy vegetable with lean proteins and healthy fats.

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Similar to rice, the cooking method of corn will also influence its glycemic index. The ideal cooking method is boiling, which will decrease the GI score of this vegetable. If you want to eat popcorn, a popular corn variety, purchase plain popcorn and avoid adding extra butter, cheese, caramels, or oils. 

Corn allergies can be caused by an immune system reaction to the proteins found in corn. Symptoms of an allergic reaction to corn include:

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• Digestive issues: nausea, vomiting, diarrhea, abdominal pain, or bloating
• Skin reactions: itching, hives, swelling of the lips, tongue, or throat
• Respiratory symptoms: sneezing, running nose, nasal congestions, wheezing, or difficulty breathing

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In severe cases, an allergic reaction can lead to anaphylaxis, which is a life-threatening situation.

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If you suspect an allergy to corn, please consult a healthcare professional.