What to Know About Mayonnaise and Is It Dairy-Free?

Medically Reviewed by Christine Mikstas, RD, LD on July 08, 2023
3 min read

You can spread it on your sandwich, mix it into your potato salad, make sauces with it, and more. There are even hair masks made of it. Mayonnaise is a popular, creamy condiment easily found in supermarkets. Some people think mayo is a dairy product because of its white coloring and creamy texture. But what is it actually made of?

Mayonnaise is made by emulsifying eggs, oil, and some type of acid, usually vinegar or lemon juice. Emulsification means combining two or more liquids that normally are unmixable. There are permanent and temporary emulsions. Vinaigrettes, made of oil and vinegar, are temporary emulsions, so you need to shake them before adding to salads. Mayo is a permanent emulsion. The lecithin in egg yolk is an effective emulsifier that keeps it together.

Dairy refers to products that are made from the milk of other mammals, such as cows, sheep, and goats. Mayonnaise doesn’t have any milk products in it, so that means it doesn’t have dairy. 

Eggs aren’t considered a dairy product, even though they are an animal product. That means if you have a dairy allergy or lactose intolerance, it’s safe to eat eggs, as well as mayonnaise, because they don’t contain any lactose. Some recipes for eggless mayonnaise use condensed milk instead of eggs, though. 

Because mayonnaise has egg in it, it’s not vegan. A food product that’s vegan is made without any animal products. Instead of eggs, commercial vegan mayonnaise brands may use aquafaba, which is the thick liquid from cooking or soaking chickpeas.

Most commercial mayo brands don’t have dairy, but they may have some of these ingredients:

  • Soybean oil
  • Distilled vinegar
  • Eggs or egg yolks
  • Salt
  • Sugar
  • Lemon juice concentrate
  • Spices and herbs for flavor and color, like paprika
  • Preservatives and food additives like calcium disodium EDTA.

Always double check the nutrition label for a list of ingredients if you have food allergies. Be aware that some mayonnaise-based dressings and sauces, such as ranch, might have dairy.  

A 14-gram serving of commercial mayo has:

  • 94 calories
  • 10 grams of fat
  • 1.6 grams of saturated fat
  • 6 grams of cholesterol
  • 0.138 milligrams of magnesium

The American Heart Association recommends that saturated fat make up 5% to 6% of your daily calories. That means that for a 2,000 calorie diet, you should be eating no more than 120 calories (13 grams) of saturated fat. Saturated fat can raise your LDL "bad" cholesterol. High levels of cholesterol can raise your odds of stroke and heart disease.

Commercial mayonnaise is available in low-fat or fat-free versions. These types of mayo use modified food starch and other emulsifiers to get the right texture. 

Making mayonnaise at home lets you control the amount of salt and other ingredients you add. Try whipping up some homemade mayonnaise to use in your sauces and spreads.

To make about 1 cup of mayonnaise, whisk together one large egg yolk and a half tablespoon of water. Blend the mixture until slightly thickened. While blending, add one drop of a neutral oil, like canola oil. Then begin to slowly stream in the oil. Keep blending as you add in the rest of the oil, for a total of 1 cup of oil. If it gets too thick, add in a little bit of water. After adding all the oil, mix in the juice of half a lemon. Season with salt to taste.

You can make mayo with any type of oil, but it’s best to use a neutral oil like canola or vegetable. If you choose to use an unrefined oil, such as extra-virgin olive oil, the emulsion may separate after several hours. Unrefined oils, as well as old or improperly stored oils, tend to make the mayonnaise unstable. 

You can store homemade mayo in the fridge for only a few days. Spread it, mix it, and savor it while you can.