Best Onions For Keto: Which Varieties To Choose

Onions are a staple in most diets, but are they keto-friendly? The answer is yes, but with some caveats. Onions are vegetables, and vegetables are generally safe to eat on the keto diet. However, onions contain carbohydrates, and the keto diet is strict about limiting carb intake. So, while onions can be a part of a keto diet, they should be consumed in moderation and with careful consideration of the overall daily carb limit.

Green onions are the most keto-friendly

Green onions, also known as scallions, are the most keto-friendly variety of onion. They have the lowest net carbs of all onions, with only 1.2 grams of net carbs in a 1/4 cup of chopped green onions. This makes them a delicious addition to keto-friendly Mexican bowls and chili, or mashed cauliflower with a dollop of sour cream.

Green onions provide the same type of oniony flavour as other onions but with a more robust taste, so you're likely to use a smaller amount in your recipes. For a 100g or 1-cup serving, you can expect green onions to provide around 7 grams of carbohydrates, 2.5 grams of dietary fibre, and just 2 grams of sugar. Most dishes will call for a much smaller serving of green onions, so the carb content of what you actually consume will likely be minimal.

Green onions are a great way to add flavour to your recipes without adding too many net carbs. They are also packed with health benefits. Compounds in onions have been reported to have a range of health benefits, including anticancer properties, antiplatelet activity, antithrombotic activity, anti-asthmatic activity, and antibiotic effects.

When it comes to keto-friendly onions, the second-best option is yellow onions. They have slightly higher net carbs than green onions, with 2.5 grams of net carbs in a 1/4 of a whole yellow onion. However, yellow onions still have a lower sugar content than other types of onions, making them a good choice for keto dieters.

In general, onions are considered keto-friendly, but it's important to monitor your serving sizes and keep your daily carb intake in check. Onions are typically used as a flavour enhancer, and a small amount can go a long way in adding flavour to your dishes.

Yellow onions are the second-best option

A cup of chopped yellow onion contains around 7g of carbohydrates and just 1g of dietary fibre. Of the 6g of net carbs in a yellow onion, only 1g comes from sugar. This makes yellow onions a keto-friendly option compared to other varieties.

For example, red onions contain approximately 15g of carbs per cup of chopped onion and around 12g of net carbs. Of these net carbs, about half come from sugars. White onions are also less keto-friendly, containing about 15g of carbohydrates per cup and 3g of dietary fibre. That brings the total net carbs to 12g with 7g of sugar per cup of chopped white onion.

Sweet onions, sometimes called Vidalia onions, are usually considered the worst option for keto dieters. They contain 12g of carbs per cup, around 1g of dietary fibre, and the most sugar of any onion: 8g.

Therefore, if you're looking to incorporate onions into your keto diet, it's best to avoid sweet onions and white onions as much as possible and favour yellow onions for their lower sugar and total carbohydrate content.

Red onions are middle-of-the-road

Per 100g, 3.5oz or 2/3 cup of red onion, there are 9.7g of total carbohydrates, 2.2g of which is fibre, leaving 7.5g of net carbohydrates. This is a relatively small amount, but it can add up if you're not careful.

A cup of chopped red onion contains approximately 15g of carbs and around 12g of net carbs. Of these net carbs, about half come from sugars. This is double the amount of carbs per serving than yellow onions, which are considered the best onion variety for keto.

However, it's unlikely that you'll be consuming a whole cup of chopped red onion in one sitting. A more realistic serving size of 1/4 of a medium red onion contains only 2.5 grams of net carbohydrates, which won't derail your keto diet.

So, while red onions may not be the best choice for keto, they can certainly be enjoyed in moderation as part of a keto meal plan.

White onions are high in carbs

White onions are indeed high in carbohydrates. A cup of chopped white onion contains about 15 grams of carbohydrates and 3 grams of dietary fibre. This brings the total net carbs to 12 grams, with 7 grams of sugar per cup. In comparison to other onions, white onions have a higher sugar content.

White onions are a crunchy variety with a less pungent aftertaste than some of their counterparts. They are commonly found in Mexican cuisine, such as salsa, guacamole, or tacos, but are also used in barbeque.

On a ketogenic diet, it is important to monitor carbohydrate consumption. White onions, while tasty and nutritious, can contribute a significant amount of carbohydrates to a meal. For those strictly adhering to a keto diet, it is advisable to limit the consumption of white onions or opt for lower-carb alternatives, such as yellow onions.

However, it is worth noting that onions, including white onions, offer multiple health benefits. They contain micronutrients such as vitamin B, vitamin C, and potassium, as well as antioxidants that may help reduce inflammation and lower the risk of cardiovascular disease and cancer.

Shallots are the worst option

While some sources claim that shallots are not suitable for a keto diet due to their high carbohydrate content, others argue that they can be enjoyed in moderation as a garnish or flavour enhancer.

Shallots, a vegetable that combines the flavours of garlic and onions, are undeniably rich in carbohydrates, with 13.6 grams of net carbs per 100-gram serving. This is certainly a concern for keto dieters, who typically aim for a daily net carb intake of 20 to 30 grams to maintain ketosis. Consuming a large quantity of shallots could easily push you beyond your carb limit and disrupt ketosis.

However, it's worth noting that shallots are typically used in small quantities as a garnish or flavouring agent. A standard serving of shallots is just one tablespoon, containing only 1.4 grams of net carbs. When used sparingly in recipes, the carb contribution from shallots becomes negligible, making them a viable option for keto dieters who want to enjoy their unique flavour.

Ultimately, the key to including shallots in a keto diet is moderation. While they may not be the best choice for a primary ingredient, using a small amount of shallots to enhance the flavour of a dish is unlikely to compromise your keto goals.

In conclusion, while shallots are high in carbohydrates and should be consumed with caution on a keto diet, they can be incorporated in small amounts without derailing your ketosis.

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