Can You Eat Onions on Keto?

When starting a ketogenic diet, the majority of people focus on the more obvious sources of carbs — namely bread, pasta and sugar. But some foods that seem healthy—like onions—can raise questions. Can you eat onions on keto? Yes, however there are some restrictions. That is the short answer. With some moderation and the right forms, onions can also be keto-friendly.

Here’s how onions break down in a ketogenic lifestyle.

Why Carbs Matter on Keto

The keto diet is a low-carbohydrate, high-fat, moderate-protein diet. The aim is to maintain your body in a state of ketosis, in which it uses fat for fuel rather than carbs.

To stay in ketosis, most people limit their carbohydrate intake to 20–50 grams of net carbs each day. Total carbs minus fiber equals net carbs. Because the carb limit is so low, every bite is precious—including vegetables.

Are Onions Keto-Friendly?

Onions can be part of a keto diet, but it’s contingent on the variety of onions, the amount, and the cooking method.

Onions, while a vegetable, have natural sugars in them, which can add to your carbs for the day. That does not mean that you need to avoid them altogether — just be aware of how much.

Onions: Carby Variety Carb Count

Here is a breakdown of the net carb content in 100 grams (about 3.5 oz) of different onion varieties:

Type of Onion	Total Carbs (g)	Fiber (g)	Net Carbs (g)
Yellow Onion	9.3	1.7	7.6
Red Onion	9.6	0.9	8.7
White Onion	9.5	1.2	8.3
Green Onion (Scallion)	7.3	2.6	4.7
Shallot	16.8	3.2	13.6

The greenest of low-carb options: Green onions (scallions)

Beware: Shallots and red onions (higher in sugar)

How to Use Onions the Right Way on Keto

• This way, you can still enjoy the flavor of onions on keto without exceeding your carb limit. Try these tips:
• Onions are a flavoring agent rather than a main element. Sauté or caramelize in butter or olive oil—this intensifies the flavor, so you can use less.
• Sauté or caramelize in butter or olive oil — this concentrates the flavor, meaning you use less.
• Combine with other low-carb veggies, such as garlic, peppers, or cauliflower, for extra bulk and flavor.
• Opt for green onions when using them for garnishes and in raw dishes—you have the lowest net carbs.

Onion Substitutes for Keto Dieters

Want to lower the carbs even further but still get that sweet-savory onion flavor? Try these alternatives:

• Suitable as a garnish, chives are low in carbohydrates and have a moderate flavor.
• Garlic — There is not much difference in pungency in small amounts; there is a slightly lower carb content.
• Leeks — Higher in carbs, but may be okay in small quantities.
• Onion powder More concentrated in flavor; use sparingly. (1 tsp = ~2g net carbs)

Sample Keto Meal with Onions

Here’s a great low-carb recipe that you can make with onions in a keto-friendly way:

Beef Stir-Fry with Green Onions (keto)

Ingredients:

• 1 lb sliced beef
• 2 tbsp coconut oil
• 1 cup chopped bell peppers
• 1/4 cup chopped green onions
• 2 cloves garlic
• 2 tbsp soy sauce or tamari

Instructions:

1. In a pan, heat oil on medium-high heat.
2. Add beef and cook until fat is browned.
3. Add in garlic and bell peppers, stir-fry for 2–3 minutes.
4. Add green onions and soy sauce, cook for another minute.
5. Serve hot — low carbs, high flavor!

The Final verdict: Are onions allowed on keto?

The answer is YES — you can eat onions on keto. The florets contribute terrific flavor and nutrition, but the carbs can add up quickly. Keep portions small, and select varieties lower in carbs, such as green onions, and consider them a flavor accent, not the star of the show.

So long as you eat them in moderation, you can reap the delectable onion flavor without kicking yourself out of ketosis.