Why Do They Say Mayonnaise Is Bad for You? Unpacking the Health Concerns

December 10, 2025 •

5 min read

A single tablespoon of regular mayonnaise can contain up to 100 calories, primarily from fat. This caloric density is a primary reason why do they say mayonnaise is bad for you, fueling misconceptions and concerns about its place in a healthy diet.

Quick Summary

Mayonnaise faces scrutiny for its high fat and calorie content, potential for processed ingredients, and omega-6 fatty acids. Understanding the difference between commercial and homemade varieties is key to assessing its impact.

Key Points

High in Fat and Calories: Regular mayonnaise is calorie-dense due to its high oil content, meaning excessive consumption can contribute to weight gain.
Processed Oils in Commercial Brands: Many store-bought mayonnaises use refined vegetable oils high in Omega-6 fatty acids, which can be pro-inflammatory if not balanced by Omega-3s.
Hidden Additives: Commercial mayos may contain unnecessary additives like added sugars, salt, and preservatives to prolong shelf life and mimic texture in lower-fat versions.
The Salmonella Myth is Debunked (for store-bought): Commercially produced mayonnaise is made with pasteurized eggs, making it safe from salmonella. The food poisoning risk comes from improperly handled foods mixed with mayo, not the condiment itself.
Homemade Offers Control: Making your own mayonnaise allows you to choose healthier oils (like avocado or olive oil) and avoid additives, though it still needs to be consumed in moderation due to high fat content.
Moderation is Key: Mayonnaise can be part of a healthy diet, but portion control is essential due to its high-calorie count.
Healthier Alternatives Exist: For a creamy texture with fewer calories and more nutrients, alternatives like Greek yogurt, hummus, or mashed avocado can be used.

Unpacking the Misconceptions About Mayonnaise

Mayonnaise is a global culinary staple, beloved for its creamy texture and rich flavor that enhances everything from sandwiches to salads. However, it has developed a reputation as an unhealthy indulgence, prompting many to ask, "Why do they say mayonnaise is bad for you?" The answer is multi-faceted, combining elements of high calorie and fat content, the presence of specific processed ingredients in commercial versions, and common misunderstandings surrounding food safety. By breaking down these concerns, a clearer, more balanced view of this popular condiment emerges.

High Calories and Fat Content

One of the most immediate reasons for mayonnaise's negative reputation is its nutritional density. Mayonnaise is a semi-solid emulsion made primarily from oil, with traditional recipes containing about 70-80% oil. This high oil content means it is very high in calories. For instance, a single tablespoon of regular, store-bought mayonnaise can contain around 90-100 calories, with most of these coming from fat.

For individuals trying to manage their weight or reduce their overall calorie intake, a heavy-handed application of mayonnaise can significantly increase the calorie count of a meal, potentially leading to weight gain over time. The key, as with many calorie-dense foods, lies in moderation and portion control. Consumed in small, measured amounts, mayonnaise can be part of a balanced diet without derailing health goals.

The Role of Refined Vegetable Oils

Another significant concern, particularly with commercial mayonnaise brands, revolves around the type of oil used. Many mainstream, store-bought mayos are made with inexpensive, refined vegetable oils like soybean or canola oil. These oils are high in Omega-6 polyunsaturated fatty acids. While Omega-6 fats are essential for health, a diet with a high ratio of Omega-6 to Omega-3 fatty acids can contribute to inflammation in the body. This imbalance has been linked to various health problems. Homemade versions or specific commercial products made with healthier oils like avocado or olive oil can mitigate this issue.

Harmful Additives and Preservatives

Store-bought mayonnaise, unlike its homemade counterpart, contains more than just oil, eggs, and acid. To extend shelf life, enhance flavor, and maintain texture, manufacturers often add ingredients that are less than ideal for health. These can include:

Added Sugars and Salts: Many brands add extra sugar and salt to improve flavor, contributing to higher overall intake of these ingredients.
Stabilizers and Thickeners: Gums and starches are often used to replace fat and mimic the creamy texture lost in low-fat versions, but can introduce less desirable processed ingredients.
Artificial Preservatives: Preservatives like calcium disodium EDTA and potassium sorbate are used to prevent spoilage. While generally considered safe in small doses, some people prefer to avoid them entirely.
Monosodium Glutamate (MSG): MSG is sometimes included as a flavor enhancer and can cause negative side effects like headaches or nausea in some individuals.

The Mayonnaise Food Safety Myth

One of the most persistent myths is that mayonnaise causes food poisoning, especially in dishes like potato salad left out at picnics. Historically, this was a valid concern with homemade mayo made with unpasteurized, raw eggs, which can carry Salmonella bacteria. However, modern commercially produced mayonnaise is made with pasteurized eggs, which eliminates the risk of salmonella contamination. In reality, the low pH from the vinegar or lemon juice in commercial mayo actually inhibits bacterial growth. The real culprit in picnic food poisoning is typically improper temperature control of other, more perishable ingredients like meat, potatoes, or cooked eggs.

Homemade vs. Store-Bought Mayonnaise: A Nutritional Comparison


Feature	Homemade Mayonnaise	Store-Bought Mayonnaise
Key Ingredients	Fresh, whole-food ingredients like pasteurized eggs, healthy oils (olive, avocado), and fresh lemon juice or vinegar.	Refined, less healthy oils (soybean, canola), pasteurized eggs, and various additives.
Healthier Fats	Allows for the use of heart-healthy monounsaturated fats from high-quality oils, improving the Omega-6 to Omega-3 balance.	Typically relies on vegetable oils high in Omega-6 fatty acids, potentially contributing to inflammation.
Additives	Contains no added sugar, salt, preservatives, or artificial ingredients, making it a cleaner, purer product.	Often includes added sugars, sodium, preservatives, thickeners, and flavor enhancers.
Shelf Life	Shorter, typically lasting one to two weeks, due to the absence of preservatives.	Long shelf life, lasting several months unopened and weeks after opening, due to preservatives.
Calorie Count	Still high in calories and fat due to the oil content, requiring portion control.	High in calories, but "light" versions can have fewer calories by replacing fat with water and other additives.

How to Choose or Make Healthier Mayonnaise

Making healthier choices with mayonnaise is possible. Here are some strategies:

Choose the right oil: Opt for brands that use healthier oils like avocado or olive oil, or better yet, make it at home where you can control the ingredients.
Control portions: Given its high-calorie nature, using a small, measured amount is key. A thin layer on a sandwich is far healthier than a thick dollop.
Opt for light or reduced-fat varieties with caution: While lower in calories, these versions may contain more processed starches and added sugars to compensate for the lost fat. Always check the ingredient list to ensure they align with your dietary goals.
Explore healthier alternatives: For a creamy texture with fewer calories, consider these excellent substitutes:
- Greek yogurt (adds protein and probiotics)
- Mashed avocado (rich in healthy fats and fiber)
- Hummus (a great source of protein and fiber)
- Pesto (made with healthy oils and nuts)

Conclusion

So, why do they say mayonnaise is bad for you? The answer isn't that it's inherently toxic, but rather that its high fat and calorie content, coupled with potentially unhealthy ingredients in commercial versions, requires mindful consumption. The health risks are largely linked to overconsumption and reliance on processed brands with unbalanced Omega-6 content and additives. By practicing moderation, choosing higher-quality brands made with healthy oils, or making your own at home, mayonnaise can be a perfectly acceptable—even beneficial—part of a balanced diet. Ultimately, the biggest factor determining the health impact of mayonnaise is the quality of the ingredients and the quantity consumed. GoodRx offers a good overview of mayo's nutritional considerations.

Frequently Asked Questions

Mayonnaise's effect on heart health depends on its ingredients and quantity. Commercial varieties with high levels of Omega-6 fatty acids from processed oils can be pro-inflammatory. However, healthier versions made with avocado or olive oil contain beneficial monounsaturated fats. For most people, dietary cholesterol in mayo does not significantly impact blood cholesterol, but excess fat and calories can contribute to heart disease risk, so moderation is key.

No, commercially produced mayonnaise does not cause food poisoning. It is made with pasteurized eggs, and its high acidity creates an environment hostile to bacteria like Salmonella. Food poisoning from dishes containing mayo is typically caused by other perishable ingredients (like cooked eggs or meat) being left at unsafe temperatures.

Homemade mayonnaise can be healthier because you control the ingredients, allowing you to use high-quality, healthier oils and avoid preservatives and added sugars. However, both are high in calories and should be consumed in moderation.

The perception that mayonnaise causes weight gain stems from its high fat and calorie content. One tablespoon can add up to 100 calories to a meal. Consuming large amounts regularly can easily lead to an excess of calories, which, over time, can result in weight gain.

Not always. While light mayos have fewer calories and fat, manufacturers often replace the fat with added sugars, starches, or thickeners to maintain flavor and texture. It's important to read the ingredient label to ensure they align with your health goals.

Excellent healthy alternatives to mayonnaise include Greek yogurt, mashed avocado, hummus, and pesto. These options can provide a creamy texture with fewer calories and more nutrients like protein, fiber, or healthy fats.

When made with heart-healthy oils like olive or avocado oil, mayonnaise provides beneficial unsaturated fats. It also contains small amounts of vitamin E and K from the egg yolk, and its fat content can help the body absorb fat-soluble vitamins from other foods like salads.

No, traditional mayonnaise is made with eggs. However, vegan mayonnaise is widely available, which uses plant-based emulsifiers and is free of eggs and animal products. People with egg allergies should always check the label carefully.