French onion soup is one of the most delicious dishes in the world. Caramelized onions, beef stew, croutons, cheese… Just thinking about the fantastic mix of spices and broth makes your mouth water.
French onion soup is a favorite of many, but it may not be a good meal for those on a keto diet. French onion soup is delicious, and we would all love to have it.

But when we're on a keto diet, we're already counting our calories and limiting our carb intake, so we can't risk eating our favorite foods unless we know they're keto-friendly.
Speaking of which, is French Onion Soup keto-friendly? Unfortunately, fellow ketoers, French Onion Soup is not keto-friendly, so you must not eat any when you're on a keto diet.
But, before you lose all hope, let's talk about this delicious concoction in detail and figure out a way to include it in your keto diet.
What is French Onion Soup?
Is French onion soup keto-friendly? Before we answer this, let's step back in time and find out how this delicacy came to delight our taste buds.
History of French Onion Soup
Most people can tell that French Onion Soup is a delicacy of France. However, you'll be surprised to know that while the modern French onion soup does come from France, its delicious history dates back way earlier than you expected.
Let's think of it this way; there are two variations of French onion soup. The first one dates back quite a few centuries to the Romans. The second dates back to France. Even with historical differences, the two are pretty similar.
In the olden times, when the Romans were still conquering land, civilians and poor people boiled onions and any available stock/water together. The onion soup was very common with Roman peasants because onions were one of the few vegetables you could grow quickly and cheaply back then.
The Romans cooked different variations of onion soups as they got their hands on better crops, and over time, onion soups were one of the most popular dishes. But with the Romans' defeat, the soup barely made it to other civilizations and remained a delicacy amongst the peasants.

Many believe that back in the 18th century in France, the then King Louis XV got hungry and only found onions, champagne, and butter. Not wanting to go back to bed on an empty stomach, he boiled the ingredients together, and voila, he made the first French onion soup.
The history of French onion soup is a little complicated, and many people question it. But we're not here to debate over French onion soup's record; we know it's incredible, so why fight over where it originated?
What Makes French Onion Soup?
I wasn't just telling you the history of French onion soup for no reason; due to its different variations, there are many recipes for this French delicacy. To make the simplest French onion soup, you would technically blend in onions, champagne, and butter, right?
While it seems from the original recipe that this is the mixture you should use, French onion soup evolved much more after King Louis XV discovered it. The simplest, tastiest, and the most authentic French onion soup recipe includes croutons, onions, wine, and gratinéed cheese.
General Nutritional Overview of French Onion Soup
French onion soup is rich in antioxidants, vitamins, and minerals. It is also a great source of fiber. However, French onion soup contains a lot of carbs, which is why the traditional recipe of French onion soup is not keto-friendly.
We will be looking at its nutritional profile in detail in a bit.
Is French Onion Soup Keto-friendly?
Before we talk about what makes French onion soup healthy or unhealthy, let's answer the central question: is French onion soup keto-friendly?
Unfortunately, French onion soup is not keto-friendly. The traditional recipe of French onion soup contains ingredients that are not keto-friendly and can upset your keto diet, even if you eat a few spoonfuls.

What French Onion Soup Ingredients are not Keto-friendly?
Let's talk about why traditional French onion soup is not keto-friendly:
Croutons
Traditional French onion soup recipes call for croutons as a topping. Croutons are re-baked bread, which is not a good fit for keto diets. Bread contains a lot of carbs and will disturb your keto diet.
Caramelized Onions
To make French onion soup, you caramelize onions in sugar. The quantity of sugar in even a single serving of French onion soup is too high for anyone on keto.
Wine/Champagne
While wine isn't necessarily something you stay away from on a keto diet, the quantity of wine in French onion soup is too much. The higher the amount of wine/champagne, the greater the carbs.
White Wheat Flour
Traditional French onion soups contain flour as a thickener. You're not supposed to eat flour on a keto diet because it is high in carbs.
Can You Make a Keto-friendly version of French Onion Soup?
Is French onion soup keto-friendly? Traditional French Onion soup is not keto-friendly, but you can make a keto-friendly version.
Keto diets are strict, but you can find alternatives for most non-keto food. If you replace all non-keto ingredients with keto-friendly ingredients, you can make a keto-friendly French onion soup.
Nutritional Profile of French Onion Soup
An estimation of the nutritional profile of French onion soup is:
Nutrients | Weightage |
Carbohydrates Sugars Dietary Fiber | 3.1g 1.1g 0.1g |
Fats Saturated fats Trans fats | 5.8g 3.6g 0.2g |
Protein | 1.8g |
Cholesterol | 15.1mg |
Minerals and Salts Sodium Calcium Iron | – 1480mg 1% 2% |
Calories | 78 |
Note: This nutritional profile is an estimation of most French onion soups that you can find in restaurants and supermarkets. It may or may not be the same across different brands.
What's Not Good for Ketoers?
You can tell from the nutritional profile of French onion soup that some dietary components aren't suitable for those on a keto diet. Let's find out more:
High Carbs
Anyone on a keto diet knows that high carbs are a no-no. You're setting back your diet when you eat high carb foods on a keto diet. French onion soup has a lot of carbs because it contains flour, wine/champagne, and croutons.
High Cholesterol
Most people on a keto diet are trying to restrict their cholesterol. A single serving of onion soup contains around 15 mg of cholesterol, and while this doesn't seem like much, for anyone who can't afford to raise their cholesterol level, this is more than enough.
Lots of Sugar
French onion soup contains a lot of sugar in the form of caramelized onions and stew. Sugar resets your diet and can increase your blood sugar level, which is why it's not suitable for anyone on a keto diet.
Nutritional Benefits of French Onion Soup
Is French onion soup keto-friendly? Unfortunately, traditional French onion soup is not keto-friendly, but that doesn't mean that French onion soup does not have much to offer.
Here are some benefits of French onion soup:
Rich in Minerals
French onion soup contains many minerals, including Sodium, Calcium, and Iron. It also contains Vitamins A, B, and C.
High Fibre Content
Adding fiber to your diet can help you regulate digestion and prevent stomach problems. French onion soup is rich in fiber,
Keto-friendly French Onion Soup Recipes
I mentioned before that you could make a keto-friendly version of French onion soup. You must replace all non-keto items with keto-friendly versions, and then you'll be able to make French onion soup without worrying about your diet:

Alternative Ingredients
Swap these ingredients to make keto-friendly French onion soup:
White Onions
Onions contain carbs, but red onions have a much higher carb content than white onions. Don't use red onions if you must eat French onion soup on a keto diet.
Keto-friendly Sweetener
You can't eat a lot of sugar when you're on a keto diet, so you must swap with a keto-friendly sweetener. You can use Erythritol or Monk fruit sweetener.
Dry White Sauvignon Blanc
Most wines contain carbs, so your best bet would be dry white sauvignon blanc.
Xanthan Gum
Traditional French onion soup recipes use flour as a thickening agent, which is high in carbs. You can use xanthan gum instead as it contains fewer carbs.
Natural, Unsalted Broth
Make your French onion soup from scratch; use beef or chicken bones to make your broth, and don't use salt.
Broths you can buy from the marketplace often contain additives and preservatives that are unsuitable for a keto diet. Some packaged broths also contain higher carbs than natural broth.
Alternative Recipes
If you'd like to follow a different recipe, you can check this or this.
Wrapping Up
Is French onion soup keto-friendly? No, a traditional French onion soup is not keto-friendly because it is rich in carbs and contains a lot of sugar. Additionally, French onion soup contains ingredients like flour and wine, which you usually avoid on a keto diet. While traditional French onion soup is not keto-friendly, if you swap non-keto ingredients with keto-friendly ingredients, you can make keto-friendly French onion soup.
Click on one of the links below to learn more about keto friendly foods: