Is mustard high in carbs? Understanding its nutritional impact on your diet

October 31, 2025 •

4 min read

A typical tablespoon of yellow mustard contains less than one gram of total carbohydrates, making it a low-carb condiment option for many diets. But the question, Is mustard high in carbs?, depends heavily on the variety you choose, particularly whether it contains added sweeteners.

Quick Summary

Most plain mustards are very low in carbohydrates, making them a suitable condiment for low-carb diets and weight management. Sweetened options like honey mustard, however, contain significant amounts of added sugar. Always check nutrition labels to identify hidden carbs.

Key Points

Plain is Low-Carb: Classic yellow, Dijon, and spicy brown mustards are generally low in carbohydrates, with less than 1g per tablespoon.
Watch for Added Sugar: Flavored mustards, especially honey mustard, are high in carbs due to added sweeteners and should be avoided on low-carb diets.
Always Read the Label: To ensure your mustard is low-carb, check the ingredients list for terms like honey, molasses, or high-fructose corn syrup.
Keto-Friendly Option: Unsweetened mustard is a great condiment for a ketogenic diet, providing flavor with minimal carb impact.
Monitor Sodium Intake: While low in carbs, many mustards can be high in sodium, which should be monitored, especially for those with blood pressure concerns.
Potential Health Benefits: Mustard seeds contain antioxidants and minerals, and studies suggest they may help regulate blood sugar and cholesterol.

For many people following a low-carb, keto, or diabetic-friendly diet, condiments can be a nutritional minefield. While a dash of flavor is desirable, it's crucial to avoid hidden sugars and carbs that can undermine dietary goals. Mustard is a popular choice, but with so many varieties, it raises the important question: is it a safe option or a high-carb trap?

The Low-Carb Profile of Plain Mustard

At its most basic, mustard is made from just a few ingredients: mustard seeds, vinegar, water, and salt. This simple formula results in a condiment that is naturally very low in carbohydrates and calories. For example, a single tablespoon of classic yellow mustard typically contains less than one gram of carbs and has minimal caloric impact.

For those on a low-carb or ketogenic diet, this means that most standard mustards are an excellent choice for adding flavor without worrying about carb counts. The negligible amount of net carbs (total carbs minus fiber) means it can be enjoyed freely without disrupting ketosis. It is also considered a "free food" for individuals with type 2 diabetes, meaning its low carb count means it will not significantly impact blood glucose levels.

The High-Carb Red Flags: Sweetened Mustards

The low-carb status of mustard changes dramatically when manufacturers add sweeteners. Honey mustard is the most well-known culprit, often containing 5–7 grams of carbs per tablespoon due to added honey. Other sweet or flavored mustards may also be loaded with molasses, high-fructose corn syrup, or fruit purees.

To ensure your condiment choice remains low-carb, reading the nutrition label is non-negotiable. Look for mustards with minimal total carbohydrates and, importantly, check the sugars listed on the nutritional information. If ingredients like honey, brown sugar, or corn syrup are high on the list, it's a clear indication of a higher-carb product that should be avoided on a restrictive diet.

Comparison of Common Mustard Varieties


Mustard Type	Carbohydrates (per tbsp)	Added Sugars?	Notes
Yellow Mustard	<1g	No, typically	Classic and safest option for low-carb diets.
Dijon Mustard	<1g	Check label for sweeteners	Generally low in carbs, but some gourmet versions may contain wine.
Spicy Brown Mustard	<1g	Check label for sweeteners	Similar to Dijon, typically low-carb but requires label-checking.
Whole Grain Mustard	~1g	Check label for sugar	Nutty flavor, usually low-carb but verify for added sugar.
Honey Mustard	5-7g	Yes, contains honey	High in sugar and carbs; best to avoid on low-carb diets.
Sweet Mustard	~4g	Yes, contains sugar/molasses	Made with added sweeteners, making it high in carbs.

Health Benefits of Mustard Beyond its Carb Count

Mustard offers more than just low calories and carbs. The seeds themselves are packed with beneficial nutrients and compounds.

Antioxidants: Mustard seeds contain antioxidants like selenium and magnesium that help fight free radicals in the body.
Minerals: It is a good source of essential minerals, including calcium, iron, manganese, phosphorus, potassium, and zinc.
Heart Health: Some research suggests that regular consumption of wholegrain mustard may help achieve healthy blood glucose and cholesterol levels.
Immunity: The minerals in mustard seeds, especially zinc and magnesium, can help strengthen the immune system.
Digestive Aid: Mustard seeds can stimulate digestion by increasing saliva production and digestive enzymes.

The Sodium Factor

While low in carbs, prepared mustard often contains a notable amount of sodium. A single tablespoon can have around 166mg of sodium. While this is not an issue for most people in moderation, those watching their sodium intake, such as individuals with high blood pressure, should be mindful of serving sizes. For individuals on a keto diet, the higher sodium content can sometimes be beneficial for balancing electrolytes, but it still requires careful monitoring.

Making the Right Choice: Tips for Adding Mustard to Your Diet

Read the Label: The number one rule for selecting a healthy mustard is to check the ingredients list for added sugars. This is especially important for flavored or gourmet options.
Use it Wisely: Standard mustards are a great way to add flavor to foods without significant calories or carbs. Use it on meats, in dressings, or mixed into dips.
Consider Making Your Own: For complete control over ingredients, you can make your own low-carb mustard at home using mustard seeds, vinegar, and spices.
Explore Other Condiments: There are many other low-carb condiments available, including hot sauce and mayonnaise (check for sugar-free versions).

Conclusion

In summary, plain, unsweetened mustard is an excellent, low-carb condiment that can be a healthy part of a balanced diet, including ketogenic and diabetes-friendly meal plans. However, flavored or sweetened versions, such as honey mustard, are high in carbs due to added sugars and should be avoided. The key to making an informed choice is to always check the nutrition label for hidden sweeteners. By selecting the right type, you can enjoy the zesty flavor of mustard and its potential health benefits while keeping your carbohydrate intake in check.

Diet Doctor offers more insights on keto-friendly condiments.

Frequently Asked Questions

Yes, most types of mustard, particularly plain yellow, Dijon, and spicy brown, are suitable for a keto diet because they are very low in carbohydrates and have no added sugar. You should, however, avoid sweetened mustards like honey mustard.

Flavored mustards that contain added sweeteners, such as honey mustard, sweet mustard, or those with fruit purees, are typically high in carbs. Honey mustard can contain 5-7 grams of carbs per tablespoon.

You can tell by reading the nutrition label. Check the ingredients list for honey, brown sugar, corn syrup, or other sweeteners. The carbohydrate and sugar counts on the nutrition facts panel will also be higher in sweetened varieties.

Yes, unsweetened mustard is generally safe for people with diabetes because its low carb content does not significantly affect blood sugar levels. The key is to choose varieties without added sugar, like classic yellow mustard.

Yes, mustard seeds contain antioxidants, omega-3 and omega-6 fatty acids, and essential minerals like selenium, magnesium, and calcium. Some research also suggests it may help regulate blood sugar and cholesterol levels.

Prepared mustard is often high in sodium. While a small amount is fine for most people, those with hypertension or who need to monitor their sodium intake should be mindful of their serving sizes.

Yes, whole grain and Dijon mustards are typically low in carbohydrates, similar to yellow mustard, and are good for low-carb diets. However, it is still best practice to check the label to ensure no sweeteners or high-carb additives have been included.