Cooked Sweet Corn Calories & Nutrition Calculator

A single medium ear (103g) of boiled yellow sweet corn provides approximately 99 calories — making corn one of the more moderate-calorie vegetables on your plate ^[1]. Per 100g, boiled yellow sweet corn delivers 96 calories, with the energy split roughly as 74% carbohydrates, 13% protein, and 13% fat by calorie contribution.

The calorie count shifts depending on the variety and how you prepare it. White sweet corn runs leaner at about 86 calories per 100g boiled, while grilling concentrates the sugars and pushes it closer to 108–120 calories per 100g depending on whether oil is added ^[1]. Raw sweet corn actually starts at a similar 86 cal/100g, but cooking concentrates nutrients as water evaporates from the kernels.

One factor worth noting: sweet corn has a glycemic index of roughly 48–55, placing it in the low-to-moderate GI range ^[4]. Unlike refined grains, its combination of fiber, protein, and moderate sugar content means the energy release is relatively gradual — a key consideration for anyone tracking their carbohydrate intake through food journaling.

What most people overlook about sweet corn is its antioxidant profile. Yellow sweet corn contains 906 mcg of lutein + zeaxanthin per 100g — both xanthophyll carotenoids that accumulate in the macula of the human retina and are associated with long-term visual wellness ^[2][5]. Among common grains and vegetables, corn is one of the richest dietary sources of these specific pigments.

But the surprises don't stop at carotenoids. Corn also contains ferulic acid, a phenolic compound found primarily in the cell walls and insoluble fiber fraction. Research has shown that corn has the highest ferulic acid content among all common cereal grains — higher than wheat, rice, and oats ^[4][7]. Ferulic acid contributes significantly to corn's total antioxidant capacity.

Here's the counterintuitive finding: cooking actually increases sweet corn's antioxidant activity. A landmark study by Dewanto et al. (2002) demonstrated that thermal processing at 115°C for 25 minutes elevated the total antioxidant activity of sweet corn by 44%, even though 25% of vitamin C was lost in the process ^[3]. The mechanism involves heat breaking down cell walls to release bound phenolic compounds. Purple and pigmented corn varieties are even richer in anthocyanins, another potent antioxidant class ^[6].

Cooking transforms sweet corn at the molecular level, and the changes aren't uniformly negative. Boiling and steaming preserve most of the starch and total sugar content but significantly reduce resistant starch and dietary fiber ^[8]. This matters because resistant starch acts similarly to fiber in the digestive tract, and its reduction after cooking changes how quickly the carbohydrates are metabolized.

A 2022 study published in *ACS Food Science & Technology* found that both boiling and steaming did not change sucrose concentrations — the dominant sugar in raw corn — but decreased minor sugars including glucose, fructose, and maltose ^[8]. Total water-soluble carbohydrates and total starch remained relatively stable, meaning the overall calorie content per 100g doesn't shift dramatically with moist-heat cooking.

On the vitamin side, cooking creates trade-offs. While vitamin C drops by about 20–25% during boiling, studies on sweet corn hybrids have shown that carotenoid and tocopherol bioavailability can increase after cooking, as heat breaks down the plant cell matrix and makes fat-soluble nutrients more accessible for absorption ^[2]. The research by Mladenovic Drinic et al. (2021) confirmed that cooking significantly increased total carotenoids and tocopherols in multiple sweet corn hybrids ^[2].

Sweet corn delivers a solid B-vitamin profile that often goes underappreciated. A 100g serving of boiled corn provides Niacin/B3 at 1.7mg (11% DV), Pantothenic Acid/B5 at 0.79mg (16% DV), Thiamine/B1 at 0.09mg (8% DV), and Vitamin B6 at 0.14mg (8% DV) ^[1]. These B-vitamins play essential roles in energy metabolism, converting the carbohydrates you eat into usable fuel.

On the mineral front, corn provides Manganese 0.17mg (7% DV), Zinc 0.62mg (6% DV), Phosphorus 77mg (6% DV), and Magnesium 26mg (6% DV) per 100g ^[1]. While these aren't headline-grabbing numbers individually, they contribute meaningfully to your daily intake — especially when corn is consumed regularly as a side dish or in combination meals.

A commonly overlooked fact: sweet corn is naturally gluten-free ^[7]. While botanically classified as a cereal grain (Zea mays), corn contains zein rather than gluten proteins, making it suitable for those with gluten-related dietary considerations. When eaten on the cob or as whole kernels, corn also functions as a whole grain, retaining the bran, germ, and endosperm — unlike refined corn products such as corn flour or corn starch, where these fractions are separated ^[5].

Sweet corn portion sizes can be confusing because the same food is measured three different ways: by ear size, cup of kernels, and raw weight. According to USDA standards, 1 medium ear (6.75–7.5 inches) yields approximately 103g of kernels, while 1 cup of cut kernels weighs about 149g ^[1]. A small ear (89g) delivers roughly 85 calories, a medium ear about 99 calories, and a large ear (118g) around 113 calories.

When choosing between fresh, frozen, and canned corn, the calorie differences are minimal — but the sodium gap is enormous. Fresh and frozen corn contain just 1–3mg sodium per 100g, while regular canned corn packs 245–285mg per 100g — that's a 100-fold increase ^[1]. Opting for "no salt added" canned varieties brings sodium back down to single digits. Frozen sweet corn is flash-frozen at peak ripeness and retains most of its nutritional profile, making it a reliable year-round substitute ^[5].

For the popcorn lovers: air-popped popcorn is technically the same species as sweet corn but has a very different nutritional density — 382 calories per 100g. However, the typical serving is just 1 cup (~8g), which means a single cup of air-popped popcorn contains only about 31 calories. This makes popcorn one of the most volume-efficient, low-calorie snacks available when air-popped and unsalted ^[1].