How Many Calories Are in Mayo

Mayonnaise is one of the most widely used condiments, found in everything from sandwiches and burgers to salads and dressings. While it adds creaminess and flavour, mayonnaise is also high in calories due to its fat content. If you’re trying to monitor your energy intake, understanding how many calories are in mayo and how different types compare can help you make more informed choices.

Calorie Content by Serving Size and Type

A standard 15g tablespoon of full-fat mayonnaise contains approximately 100 to 110 calories, depending on the brand and recipe. The majority of these calories come from fat, especially oil, which is the primary ingredient in traditional mayo. A 10g teaspoon has around 65 to 75 calories, which still makes it a calorie-dense condiment for its size.

Light mayonnaise, often labelled as reduced-fat or low-fat, usually contains 35 to 50 calories per tablespoon, depending on how much oil has been replaced with water or other thickening agents. Vegan mayonnaise, which typically uses plant-based oils and starches instead of eggs, sits somewhere in the middle, averaging around 60 to 80 calories per tablespoon, though this varies by brand and ingredients.

Some “extra light” versions may go as low as 10 to 20 calories per tablespoon, but these tend to be heavily processed and may contain added stabilisers or artificial sweeteners.

Nutritional Breakdown of Mayonnaise

Traditional full-fat mayonnaise is made primarily from oil, egg yolk, vinegar or lemon juice, and sometimes mustard or seasonings. Its macronutrient profile is almost entirely fat, with one tablespoon containing around 11 grams of fat, of which 1 to 2 grams are saturated fat.

There is little to no protein, fibre or carbohydrate in standard mayo. It offers trace amounts of vitamin E and omega-3 or omega-6 fatty acids, depending on the type of oil used, but no significant levels of other nutrients. It contains a small amount of sodium and cholesterol, especially in versions made with egg yolk.

Light and vegan mayonnaises tend to have less fat and fewer calories, but may include added sugar, starch or modified food ingredients to maintain texture and flavour.

Benefits and Downsides of Eating Mayo

The main benefit of mayo is its ability to enhance flavour and texture in a wide range of meals. It adds moisture to sandwiches, acts as a base for dressings and dips, and can improve the mouthfeel of lean proteins and vegetables. Some versions made with olive oil or avocado oil may offer healthier fats, including monounsaturated fatty acids.

On the downside, mayonnaise is an energy-dense food that is easy to overuse. Because it’s spread thinly or mixed into dishes, many people underestimate how much they’ve eaten. A few tablespoons across a sandwich or salad can easily add 200 to 300 extra calories, with very little satiety in return.

It’s also low in nutrients, especially compared to more wholefood-based toppings like hummus, yoghurt or avocado. In large quantities, the saturated fat and cholesterol content in egg-based mayonnaise may also contribute to heart health concerns for some individuals, particularly if combined with a high-fat diet overall.

How Mayo Fits Into Your Diet

Mayonnaise can fit into a healthy diet when used sparingly and mindfully. The key is portion control. Measuring out a single tablespoon rather than guessing can keep calorie intake in check. Using it as a flavour enhancer rather than the base of a dish also helps reduce reliance on it.

If you're trying to reduce calorie intake or manage weight, switching to a light or low-fat version can help. Better still, using a small amount of full-fat mayo combined with yoghurt or mustard can give you the same flavour with fewer calories overall.

For those on low-carb or keto diets, full-fat mayo is often acceptable due to its low carbohydrate content, although quality of fat sources should still be considered.

Glycaemic Index of Mayo

Mayonnaise has a glycaemic index of virtually zero, as it contains no sugar or starch in its classic form. This means it does not raise blood sugar levels and is generally safe for people managing diabetes or insulin resistance, especially when consumed in moderation.

Light or flavoured varieties may include added sugars or starches, which slightly increase the glycaemic load, so it’s important to check the label if blood sugar control is a concern.

How Mayonnaise Is Made and What It Contains

Traditional mayonnaise is made by slowly whisking oil into a mixture of egg yolks, vinegar or lemon juice and mustard, forming an emulsion. This creates its creamy texture and stability. Most shop-bought versions use rapeseed oil, sunflower oil or soybean oil, and stabilisers like xanthan gum or starch to maintain consistency over time.

Vegan mayonnaise replaces the egg with aquafaba, pea protein or starch, and may use similar oil bases. Light versions may replace part of the oil with water, air or gelled starches.

Some brands also add preservatives, flavour enhancers, or sweeteners, especially in flavoured versions like garlic mayo or chilli mayo. As a result, ingredient lists can be long, particularly for shelf-stable versions.

Healthier Alternatives to Traditional Mayo

For a lower-calorie and more nutrient-dense spread, you can use Greek yoghurt, cottage cheese, mashed avocado or blended silken tofu in place of mayo. These alternatives offer protein, fibre or healthy fats, with fewer calories and more vitamins and minerals.

You can also make your own lighter mayo at home using olive oil, mustard and egg yolk, controlling the type of fat and salt content. For added flavour without extra fat, consider mixing yoghurt with herbs, lemon juice or garlic to create a tangy dressing or spread.

Summary

A tablespoon of full-fat mayonnaise contains about 100 to 110 calories, most of which come from fat. Lighter and vegan versions range from 20 to 80 calories per tablespoon, depending on formulation. While mayo can enhance meals and add richness, it's calorie-dense and should be used in moderation if you're watching your intake. Choosing light or homemade alternatives can help you enjoy the taste while keeping calories under control.