Is red onion healthier than white onion?

In this blog post, we will answer the following question: Is Red Onion healthier than white onion? We will explain the differences between red, white, and yellow onions.

Is red onion healthier than white onion?

The purple or red onion is healthier than white onion because it is richer in antioxidants since it contains anthocyanins, the pigments responsible for its red or purple color and that helps prevent cancer and heart disease. Red onions also help preserve memory, take care of the urinary tract, and delay the aging process.

The purple or red onion contains more than the white, quercetin, a nutrient with great antioxidant power that helps protect cells against oxidative damage and prevent malignant tumors, in addition, it has an anti-inflammatory and anti-allergic effect, and favors the circulation of blood. Quercetin has been used as a therapy for cardiovascular diseases, high cholesterol, cataracts due to diabetes, inflammations, among others.

The red onion would be an effective natural remedy to regulate blood glucose levels in people living with diabetes. According to researchers from the University of Gezira, in Sudan, glucokinase, as well as its rich content in flavonoids and sulfur, have a hypoglycemic effect and stimulate the secretion of pancreatic juice that helps to break down fats, proteins, and carbohydrates from food.

A good way to treat osteoporosis naturally is by increasing your consumption of red onion. According to researchers from Bone Biology at the University of Bern, Switzerland, it increases bone density with a benefit greater than that of calcitonin, which is the drug most used to treat osteoporosis that usually occurs as a result of menopause.

The red onion is a great friend of our digestive system, it fights constipation and helps prevent intestinal parasites, thanks to its rich content in quercetin. In addition, the quinine it contains stimulates the liver, gallbladder, pancreas and favors the functions of the stomach and has a neutralizing effect on acids, thereby activating the secretion of gastric juices that promote the health of the intestinal flora.

On the other hand, the white onion is one of the most powerful cardio protectors that exist in nature. The alliinase enzyme it contains helps to thin the blood and reduce the levels of “bad” cholesterol, thus maintaining the elasticity of the arteries and cleaning the fat. A study from the University of Pennsylvania says that eating a medium onion a day reduces cardiovascular risk and cholesterol by 15%.

In addition to making us cry, it seems that white or purple onion can be very effective in the fight against cancer. A group of scientists from the Autonomous University of Madrid discovered that the outer skin of the onion is rich in a set of substances that help prevent cancer. Sulfur compounds, quercetin, and selenium would be useful in cancer prevention due to their antioxidant effects.

Yellow onion: the onion par excellence

The conventional onion, which we all have at home, is one that, traditionally, grew during the summer and was harvested already ripe in the autumn. That is why, although it is sold all year round, it is at this time when they taste sweeter.

It is rich in sulfur compounds, drier and easier to store in a cool, dry place, without the need for refrigeration, for several months.

Although it is acceptable raw, it is the quintessential onion for cooking. Depending on age, it stings more or less but always becomes softer when warming up. It is the ideal variety to prepare the base of any dish and also to caramelize.

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White onion: the friend of your salads

These onions were the spring ones, as they were planted as shoots in late fall and harvested before they were fully ripe, the following spring and early summer. Today they are found all year round and their flavor does not differ too much between seasons. Now, they are worse preserved. They can also be stored in a cool and dry place, but they hold less than conventional onions.

This type of onion is ideal to consume raw, as its flavor is smoother and its texture is more crunchy than that of the yellow variety. Thinly sliced, it is the ideal onion to add to a salad, but it is also great when you need to cook quickly, such as a pizza, or for dishes where we want a softer and sweeter flavor, as is the case of onion soup. It is also a particularly popular variety in Latin America.

Red onion: a note of color

The red onion is similar to the white one, but it is pigmented by water-soluble anthocyanins, which gives it its characteristic color. This, in any case, is only present in the superficial layers of each leaf scale and when cooked its color is diluted and faded.

In terms of flavor and preservation, they are similar to white onions, although slightly stronger and spicier. They are found all year round, but in summer and early fall, they have a milder flavor as their acidity intensifies throughout the winter.

It does not make much sense to use this onion for hot preparations, for which we will obtain better results with the yellow variety, but it works wonderfully in salads or to make pickles or macerations, such as ceviche, where its presence is mandatory.

Vidalia onion: the sweetest variety

The Vidalia onion owes its surname to the town of the same name, in the state of Georgia (USA). It is actually a spring onion that is grown in soils with little sulfur and therefore has half, or less, the usual amounts of chemical defenses based on compounds of this mineral. This makes it much smoother and sweeter. Although again, it is available all year round, the ideal is to buy them between the end of April and the beginning of September.

Although its flavor is more similar to that of white onion, its external appearance makes it easily confused with conventional yellow onion, although it is usually somewhat flatter.  It is a great option to eat raw, as it is the least strong option, and it is also the ideal variety for making onion rings.


No kitchen is complete if there are no onions. They may make you cry, but they are on your side when it comes to health. Both the white and the purple or red have vitamins A, B, and C, calcium, magnesium, phosphorus, iron, and potassium. 

Its main assets are allicin and alliin, a component to which several medicinal properties are attributed, including anti-inflammatory and antioxidant effects.

So, is red onion healthier than white onion? The final answer is yes or no, depending on what properties you are looking for. No matter the color of the onion, it is an amazing ingredient to have in your kitchen!

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