How Many Calories in a Corn of Cob

Corn on the cob is a summer staple and a favourite on barbecues, often served hot, buttery and straight off the grill. Sweet, juicy and satisfying, it's easy to assume corn is a light vegetable — but in truth, it sits closer to a starchy carbohydrate like potatoes or rice. So how many calories are in a corn on the cob, and how does it impact your diet? That answer depends on size, cooking method, and toppings. Here’s what you need to know.

Calories in Corn on the Cob by Size and Preparation

A medium-sized ear of corn, which weighs roughly 90 to 100 grams once cooked and without the husk, contains around 90 to 100 calories. This is for plain, boiled or steamed corn with no added butter, oil or seasoning.

If you add butter, the calorie count increases dramatically. One teaspoon of butter adds about 35 calories. A generous coating can add 100 or more calories easily. Grilled corn, when prepared without added fat, remains close to the same calorie range — around 100 calories per cob — but using oil or basting it during grilling can push the total higher.

Larger cobs, which are often served at restaurants or barbecues, can weigh up to 130g or more, raising the natural calorie count to 120 or even 140 calories, especially if served with rich toppings or sauces.

Nutritional Breakdown of Corn on the Cob

Corn is a starchy vegetable, which means it's higher in carbohydrates than leafy greens or non-starchy vegetables. A typical corn on the cob provides about 3g of protein, 1 to 2g of fat (unless buttered), and 19 to 25g of carbohydrates, of which around 6 to 8g are sugars. It also includes around 2 to 3g of fibre, which supports digestion.

Corn contains several beneficial micronutrients, including vitamin C, magnesium, potassium, and small amounts of B vitamins like folate and thiamine. It’s also a source of lutein and zeaxanthin, antioxidants that support eye health.

How Corn on the Cob Is Grown and Made

Corn on the cob comes from maize plants, with ears harvested when the kernels are in the "milk stage" — sweet, soft and not fully dried. This is known as sweetcorn, distinct from the hard, dry kernels used for popcorn or flour.

The cobs are usually boiled, steamed or grilled, and can be eaten straight off the cob or sliced and served in salads or salsas. Corn can also be roasted in foil or cooked in the husk to preserve moisture. It’s most popular during summer months when fresh corn is in season, although frozen and vacuum-packed cobs are available year-round.

Benefits of Eating Corn on the Cob

Corn on the cob offers a combination of slow-release energy, fibre and natural sweetness, making it both satisfying and nutritious. It provides plant-based carbohydrates without the additives or preservatives found in many processed starches.

The fibre content supports digestion and gut health, while the antioxidants in the yellow pigment — like lutein — help protect vision and may reduce oxidative stress in the body. When eaten in whole form, like on the cob, corn retains more of its nutrients and promotes mindful eating, as it takes longer to chew and eat compared to processed foods.

It’s also naturally gluten-free, making it suitable for people with coeliac disease or gluten sensitivity.

Downsides of Corn on the Cob

The main downside is that corn is still a carbohydrate-heavy food, and portion size can creep up quickly — especially at barbecues or buffets. When drenched in butter, mayonnaise, cheese or creamy sauces, a single cob can go from 100 calories to over 300, depending on what’s added.

Corn is also higher in natural sugars than most vegetables, and may not be ideal for people on strict low-carb or ketogenic diets. For individuals with insulin resistance or diabetes, corn should be eaten in moderation and ideally paired with protein or fat to help slow blood sugar absorption.

Another consideration is digestion. Some people find that corn, particularly the kernels’ outer skins, can be difficult to fully break down, occasionally leading to bloating or visible remnants in stool.

Impact on Your Diet

Corn on the cob can easily fit into a balanced diet when portioned properly and prepared with care. It provides energy, fibre and a mild natural sweetness, which can help curb cravings for more refined carbs or sugar.

As a side dish, corn is best served plain, lightly seasoned or with minimal fat added. If you’re tracking calories, it's worth measuring how much butter or oil you use, as toppings can account for more than half of the calories in a single serving.

Corn is also a good option for post-workout recovery, offering a clean carbohydrate source to replenish glycogen stores, especially when paired with lean protein.

Where Corn on the Cob Falls on the GI Index

Corn on the cob sits in the medium range on the glycaemic index (GI), typically around 60 depending on how it’s cooked. Boiled corn has a slightly lower GI, while grilled or roasted corn can be slightly higher. The GI rises more dramatically when corn is processed — as in cornmeal, cornflakes or popcorn — but whole corn on the cob tends to produce a moderate blood sugar response.

Pairing it with fats or proteins, such as grilled chicken or a small amount of olive oil, can help reduce the glycaemic impact and promote more stable energy levels.

Healthier Alternatives and Adjustments

If you're looking for a lower-carb side dish, you could opt for courgette, cauliflower rice or leafy green salads, but for most people, corn on the cob doesn’t need to be replaced — just moderated. Choosing herb seasoning, lime juice or spices instead of butter and cheese helps keep the calories low while still delivering flavour.

You can also try cutting the corn off the cob and mixing it with diced tomatoes, black beans and avocado for a high-fibre, high-flavour side salad that balances carbs with protein and healthy fats.

Corn on the Cob Isn’t Just a Vegetable

One thing that often surprises people is that corn isn’t technically a vegetable in the nutritional sense. It’s classified as a starchy carbohydrate, like potatoes or rice. This means it’s not as low in calories as green vegetables like broccoli or spinach. That matters when you're structuring a meal — if you treat corn as a side veg and also serve rice or bread, you could be doubling up on starches without realising it.

Understanding corn’s place as a grain-like carb helps manage portions more effectively. Instead of pairing it with pasta or mashed potatoes, it makes more sense to combine corn with protein and non-starchy vegetables for a more balanced plate.

Sauces and Toppings Add More Than Flavour

One of the biggest calorie traps with corn on the cob is how it's served. While plain corn is relatively light, once you add melted butter, mayonnaise, cheese, garlic oil, or creamy dressings, you’re often adding more calories than the corn itself contains. In street food settings, a single cob might be coated in sauces, sprinkled with toppings and dusted with sugar or spice blends — sometimes taking the calorie count past 250 or 300 per cob.

It’s easy to assume a grilled cob is still a healthy option, but if it’s been basted in oil throughout cooking or served with a generous knob of butter, the calorie balance shifts significantly. These additions don’t just bring flavour — they change the nutritional profile entirely.

Hidden Sugars in Sweetcorn Varieties

Modern sweetcorn has been selectively bred for higher sugar content, especially varieties found in supermarkets and fast food outlets. While it’s all natural sugar, a medium cob can still contain 6 to 8 grams of sugar, which is quite a bit compared to other vegetables. That sweetness is part of its appeal, but it’s worth noting if you’re managing blood sugar levels or carbohydrate intake.

Although these sugars are naturally occurring and absorbed more slowly due to the fibre content, it still contributes to your overall sugar and carb load. It’s why corn, unlike leafy greens, should be eaten in measured portions, particularly by those with diabetes or insulin resistance.

Portion Size and Frequency Matter

It’s easy to eat more corn than you realise, especially when it’s served sliced off the cob or mixed into salads, soups, or rice dishes. A half-cob might only add 45 calories, but a full large cob, topped with butter or salt, can jump to over 150. And if you’re at a barbecue or buffet where cobs are endless, it’s easy to go back for seconds or thirds.

This is especially true when corn is eaten mindlessly while chatting or drinking, as the natural sweetness and chewiness makes it feel lighter than it is. Over the course of a meal, this can lead to unintentional calorie creep.

Corn on the Cob and Satiety

One of the advantages of eating corn straight from the cob is that it promotes slower, more mindful eating. You chew more thoroughly, eat with your hands, and generally eat more slowly — which supports better satiety. This contrasts with refined corn-based products like crisps or cornmeal, which are easy to overconsume.

Because it takes time to eat and digest, a corn on the cob can help you feel full for longer than other fast carbs. This makes it a useful inclusion in meals where you’re trying to control portion sizes or avoid overeating refined starches.

Summary

A corn on the cob contains around 90 to 100 calories, depending on size and cooking method. When eaten plain or lightly seasoned, it’s a nutrient-rich source of fibre, slow-release carbs and antioxidants. However, heavy toppings like butter and cheese can dramatically raise the calorie count. Corn on the cob ranks mid-range on the GI index, offering a steady energy source when balanced with protein or fat. It’s a satisfying, naturally sweet whole food that works well in most diets — especially when kept simple and portioned with awareness.