Onions aren’t just for crying. Get to know all its advantages, you will be amazed!

Onions are the irreplaceable basis of almost every known recipe.

However, the fact that it can also serve as the main and only raw material is often forgotten.

Do you know onion dishes? They won’t put a strain on the family budget, and they’re also extremely healthy!

How not to cry when cutting, why do onions rot in the presence of fruit and when to choose the red or white option?

All useful information, advice, tips and tricks – you will find all this in this article.

The healing power of the ancient onion

Kitchen onion, also called garden onion and common onion, is the most cultivated plant from the genus Allium, which includes, for example, garlic, chives and leeks. Onion ( Allium cepa) is an ancient vegetable that has been cultivated by humans for over 7,000 years. In the past, it was popular mainly for its potential healing abilities and effects. Only over time has it become a basic and indispensable ingredient of the human diet and every kitchen.

In Egypt, the onion was considered a symbol of eternal life, which is why its image appears on the walls of pyramids and tombs. It also became part of mummification and funerary rites for its “magical” powers, as evidenced by the mummy of Pharaoh Ramesses IV, where onion remains were found in the eye sockets.

Found historical writings confirm that the Roman culture used onions on a daily basis, to such an extent that, specifically in Pompeii, entire large gardens were built for its cultivation. It was used to treat vision, cold sores and gingivitis. Gladiators then used onion ointment to strengthen their muscles and skin before matches.

What is an onion?

The bulb is the storage organ of the whole plant, similar to, for example, the bulb of a turnip. It forms from the lower part of the stem and subsequently nourishes the roots, leaves and flowers that grow from it.

Are onions really healthy?

Onions contain a minimum of fat, so they are non-caloric and do not contribute to weight gain. Individual varieties differ from each other in the amount of specific antioxidants and compounds.

White onions provide the least flavonoids, specifically 12 times less than yellow onions. Flavonoids (dyes) have a beneficial effect on human health in several ways. Red onions also contain anthocyanins, red pigments that have even greater antioxidant capabilities. That is why red onions are considered the healthiest, followed by yellow and lastly white onions.

Red onion
100 g 1
Yellow onion
100 g 2
White onion
100 g 3
Water 88.6 g 90.1 g 91.3 g
Energy value 44 kcal 38 kcal 36 kcal
Proteins 0.94 g 0.83 g 0.89 g
Fats 0.1 g 0.05 g 0.13 g
Carbohydrates 9.93 g 8.61 g 7.68 g
Fiber 3.97 g 2.71 g 1.2 g
Sugars 5.76 g 5.82 g 5.76 g
Calcium 17 mg 15 mg 21 mg
Magnesium 11.4 mg 9 mg 9.3 mg
Phosphorus 41 mg 34 mg 29 mg

Onions destroy cancer cells

Onion consumption is associated with the prevention of colon, rectal and stomach cancer. Studies have shown that people who consume cooked onions daily reduce their risk of developing stomach cancer by up to 22% 4 .

Among other things, onions contain sulfur compounds that also have effective cancer-fighting abilities. For example, the compound onionin A blocks the development of tumors and slows the spread of lung, ovarian and uterine cancer 5 . It also significantly enhances the effect of chemical anticancer treatment, especially in patients with an advanced stage of the disease.

According to research, onions included in the diet of breast cancer patients significantly reduced the side effects of chemotherapy. Raw yellow onion suppressed adverse effects of treatment such as insulin resistance and hyperglycemia 6 .

Strong bones thanks to onions

Onions may be an important factor affecting bone health. Scientific research has shown that people who consume at least one onion per day have a 5% higher total bone density. In women aged 50 and over, this fact reduced the risk of hip fracture by up to 20% 7 .

Onions and bacteria

Spicy onions can also kill potentially very dangerous bacteria, such as Staphylococcus aureus (golden staphylococcus) and Vibrio cholerae (the causative agent of cholera). The flavonoid quercetin, which is contained in onion skins, also effectively kills the MRSA bacteria 8 . It is mostly resistant to antibiotics and causes difficult-to-treat infections throughout the human body.

Reducing the risk of a heart attack and treating asthma

The aforementioned quercetin is a really valuable antioxidant. It prevents bad cholesterol from clogging the arteries and thus greatly reduces the risk of heart attack and stroke 9 . At the same time, it has strong antibacterial properties that can alleviate bladder inflammation and respiratory tract infections. Quercetin from onions also prevents the release of histamine, so it acts as an antihistamine 10 . In the future, it could thus be part of treatment procedures for allergies, asthma and bronchitis.

Onions and COVID-19

Quercetin is also an antiviral, anti-inflammatory, and analgesic compound that recent studies have shown to have therapeutic potential as a low-cost treatment for patients with SARS-CoV-2. The effectiveness has been confirmed mainly in cases with a life-threatening course of COVID-19, where the so-called cytokine storm is usually directly responsible for the patient’s death. Onion quercetin blocks the regulators that trigger inflammation and the subsequent storm 11 . In addition, its effects can be greatly enhanced by combining it with “ordinary” vitamin C 12 .

Excessive consumption of onions

In sensitive individuals, excessive consumption of (mainly raw) onions can cause digestive problems. Bloating is common, as are abdominal cramps, nausea, vomiting, diarrhea and heartburn. People who suffer from irritable bowel syndrome should include raw onions in their diet in a reasonable amount.

What is onion good for or homemade onion cures and tricks

  • Raw onion slices applied to a bee sting will relieve pain, swelling and itching.
  • A whole raw onion, consumed just before bed, is likely to clear the nasal passages and trigger a cold by morning.
  • Blended onion mixed with turmeric effectively heals skin irritations, for example from cleaning products.
  • A freshly cut onion, held to the nose and then inhaling its aroma, usually stops bleeding from the nostrils.
  • Homemade onion tea treats coughs caused by flu or colds.

Are chopped onions toxic?

One of the most common myths about onions , which includes several misinformation warnings:

“Leftover chopped onions you keep in the fridge can cause food poisoning the next day.”

“The onion is a magnet for bacteria, it absorbs all of them and becomes poisonous.”

“If you came down with the flu out of the blue, it might be the onions that were sitting in your fridge.”

Onions are not toxic to humans! As several food safety centers point out, all of these myths are false. The chemical composition of the onion does not even allow the growth of bacteria, because it is too acidic. So onions do not attract bacteria, but on the contrary – inhibit and destroy them. It can kill even the microorganisms that normally cause food poisoning.

It is completely safe whether sliced or whole, raw onions can last up to 7 days in the fridge without spoiling.

Onions and animals

However, the thiosulfates that onions contain cannot be processed by animal metabolism. Therefore, all plants of the genus Allium are toxic to dogs and cats, both in raw and cooked or dried form. In animals, ingestion of onions can cause damage to red blood cells or severe damage to the digestive tract and kidneys, which can lead to total collapse and subsequent death.

How not to cry while cutting onions

Slicing onions commonly causes burning of the eyes and subsequent tearing or crying. When portioning, a volatile liquid is released, which produces an aerosol. The main purpose of this gas is to protect the onion, so it serves as a defense mechanism. It very quickly penetrates the eye nerves and irritates them.

  • Cut the root of the onion last, it contains the most volatile liquids.
  • First, soak the onion in water for 10 minutes and then chop.
  • Before slicing, place the onion in the freezer for a few minutes.

The good news is that the more you cut onions, the less your eyes will cry as they get used to it.

Onions are a basic ingredient in every kitchen

It is not called a gastronomic treasure for nothing. A number of recipes would most likely not even exist without onions. It is truly the “foundational building block” of every world cuisine, has a wide range of uses and gives dishes exactly the taste they should have.

How to cut an onion? Check out some handy ways:

3 Ways To Chop Onions Like A Pro

Onion recipes

  • Slightly golden or caramelized onions are part of most soups, sauces and roasts. But don’t be afraid to add it to homemade bread, for example together with fried bacon.

  • As for using onions in sauces, try cooking straightonion sauce . It is ready in 15 minutes and if you are missing cabbage at home with roast meat and dumplings, it will replace it brilliantly.

  • Just like other vegetables or potatoes, you can also grill or bake onions in the oven and then serve them as a side dish to meat.

  • It is common knowledge that onions are the base of almost every soup. But did you know that you can also cook a great onion soup? It’s cheap, fast, tasty and, on top of that, extremely healthy. Therefore, do not forget to try the traditional onion recipe .

  • Do you know the so-called quiche? These savory pies are very popular and onions play a very important role in them. It is combined not only with egg, but also with zucchini, spinach, ham and potatoes. A pure onion pie is also a great option!

  • Famous and world-famous – this isthe recipe for fried onion rings . These crispy canapés are simply the ideal treat for larger celebrations; they won’t put a strain on your budget and everyone adores them.

  • Another popular dish is the so-calledonion marmalade . From the name you might think it is sweet, but on the contrary – it is a spicy, slightly salty spread known as onion chutney.

How to Caramelize Onions

Caramelized onions are a very versatile ingredient. First of all, it will keep well in the fridge for up to a month, and secondly, you can incorporate it into any recipe you can think of. It is most often added to burgers, hot dogs, spreads, soups, but also under meat or on pizza.

Raw materials:

  • 4 large onions
  • 2 tablespoons of butter or olive oil
  • salt

Procedure :

  • Melt and heat the butter (olive oil) in a large, deep pan.
  • Cut the onion into half rings and add them to the pan.
  • Season with a pinch of salt and mix well.
  • Sauté gently, on a low heat for at least 1 hour, the onions will stick to the pan as they caramelize – that’s okay, stir every 5 minutes.
  • Once the onions have turned dark brown, softened and become sticky, remove the pan from the heat.
  • Allow the caramelized onions to cool and then store in the refrigerator, preferably in sterilized jars.

Onions and bad breath

Onions, especially raw ones, cause bad breath. Fortunately, there are foods that can suppress this unpleasant smell. Chewed coffee beans or cloves, as well as cinnamon, honey, mustard, thyme, sage, parsley, aloe vera and high-percentage chocolate will guarantee fresh breath.

Onion products or what is sold in stores

You can buy onions in several forms. In addition to fresh and raw, also for example caramelized, i.e. already prepared for sauces and soups. Similarly, fried/roasted, which is added to roast meat or onion pastries.

You can also find frozen, canned or pickled onions and chives in stores. Recently, the popularity of onion powder, which is used as a spice, has increased considerably. Onion paste has a similar use, it is often used to season pasta or dressings or marinades.

Another product is onion oil. The one that is produced by extraction from onion seeds is available mainly in drugstores. Due to the higher production and therefore sales price, it is not used for consumption, but as a cosmetic oil. Effectively nourishes the scalp and promotes hair growth.

Edible cooking oil, on the other hand, isn’t quite oniony, even though it’s called that. Its basis is virgin olive oil, in which the onions are only left to infuse.

When to plant onions, their cultivation and harvest

Onions thrive best in cooler weather. However, it is not frost-resistant, so it is planted in March and April; when temperatures no longer drop below -1 °C. Although the onion is normally a biennial plant, it works like an annual. It is harvested in the autumn of the first year, after the outer layers of the onion (skin) have dried.

Tip! The more sulfur the soil contains, the hotter the onions grown in it will be. Choose sandy soil for sweeter onions, clay soil for sharper ones.

Types and varieties of onions

Onions have many types and even more specific varieties. They differ from each other in the length of the growing day, taste, size and skin color. However, they are all considered common onions, i.e. Allium cepa, except shallots, which in 2010 were classified as a separate species of Allium cepa var. aggregate.


There are significant differences between shallots and onions. Shallots have a milder, less hot taste, so they are often used raw to freshen up dishes. It also has a different structure, it softens much faster during heat treatment, which is why it is more suitable for sauce bases; caramelized forms a thick broth. In the comprehensive article on shallots, you will find all the information and specific tips on processing.

Recipes that include shallots: Brynzová spread , chicken broth, Thai-style squid , chicken supreme in many variations

Onions Shallots
source: specialtyproduce.com

Spring onion

While the classic onion is eaten when it is ripe, the spring onion is its unripe stage. These young plants are harvested before the so-called bulbing, i.e. when they do not have a developed bulb. Their green, tubular, slightly pungent leaves are used in the kitchen.

Spring onion is suitable for recipes: smoked mackerel spread , vegetable salad, grilled spring onion, Mexican burrito ,Japanese and Czech cabbage pancakes

Spring onion tied
source: mashed.com

Yellow (brown) onion

The skins of this onion, as the name itself suggests, are yellow to light brown in color. Basic varieties contain a higher content of sulfur compounds, so they are more pungent and pronounced, especially raw. Yellow onions are commonly available in stores, caramelized to give sauces and soups a dark brown color and a sweet taste.

The most cultivated varieties of yellow onions: Yellow Granex, Walla Walla, Yellow Ebenezer

Two yellow onions with skin
source: treehugger.com

Red (purple) onion

This onion has red, sometimes purple skins. It has a distinct juicy taste and is noticeably sweeter than yellow onions. It is therefore suitable for making onion chutney aka marmalade. It is also used because of its rich color and not only in dishes; its peels are commonly used as a natural dye used to dye Easter eggs.

The most cultivated varieties of red onion: Red Burgundy, Red Wethersfield, Tropea

Red onion with skin cut into slices

White onion

White onions have very versatile uses. Its taste is more bland and indistinct, so it is added to dishes where it is desirable not to overpower the other flavors. It is also often included in fermented, canned and pickled mixes or frozen sandwiches and baguettes.

The most cultivated varieties of white onions: Crystal White Wax, Snow White

White onions with skin
source: epicurious.com

Pearl onions

These small bulbs of white varieties are harvested at mid-ripening. That is, when they are small, sweet, but at the same time already slightly pungent. They are used whole and most often for canning; thus, to most of the population, they are known as pickled onions in a jar.

White pearl onions with skin
source: specialtyproduce.com

Sweet onion

Some red, yellow and white onion cultivars continue to be bred into so-called sweet onion varieties. Their popularity is skyrocketing, as they are extremely sweet compared to non-bred varieties. For that reason, there is no need to cook them and they are mainly eaten raw.

The most famous sweet onion varieties: yellow Vidalia, red Bermuda, white White Granex

Dividing onions according to day length

To form the bulbs themselves, the plants need a certain interval of daylight. Short-day varieties require a day long of 10-12 hours, long-day 14-16 hours.

red (purple) yellow (brown) white
short day varieties Bermuda,
Red Burgundy
Yellow Granex,
Walla Walla
White Granex,
Crystal White Wax
long day varieties Red Wethersfield,
Yellow Ebenezer Snow White

How to store onions?

Most crops need ethylene to ripen. However, onions are very sensitive to this gas and will start to rot when in contact with it. Therefore, never store it near fruits that naturally ripen on their own and thus release ethylene. These are, for example, apples, pears, bananas, avocados, mangoes, peaches, plums, strawberries, tomatoes and potatoes.

Onions are stored loosely hanging, in a dry, cool and above all sufficiently ventilated place, never in containers or microtene bags. In an ideal environment, it has a shelf life of up to 2 months. Sweet onion cultivars contain much more water and sugar, cutting their shelf life roughly in half. Onions can also be stored in the refrigerator, but this is not a suitable solution – it absorbs moisture from other foods and spoils faster.

Milan & Ondra

We are both fans of good food and enjoy cooking. On this website, we want to inspire you with traditional, but also less common recipes. We will be happy if you try our recipes and let us know how you liked them. Bon appetite! :)