Onion, fiber, antioxidants

The onion is considered, with the garlic, the lemon, the honey, the walnut and the apple, a medicinal food. However, on the other hand, many people reject it because of its strong flavor, because it repeats, because it causes flatulence ... So, where are we? Is onion advisable or not?

Low in calories and rich in fiber

The onion belongs to the genus Allium, of the liliaceae family, which also includes chives, chives, leeks ... Like most vegetables, the onion is very rich in waterIn fact, water represents about 90% of its composition. Apart from this, its high content of fiber, vitamins and minerals, and its low caloric intake is remarkable.

For all this it is considered a regulating food. Regarding its mineral content, onions provide potassium, calcium, iron, phosphorus, magnesium ... although it does not stand out for any of them and it should be taken into account that bioavailability of iron and calcium It is not very high since, for example, the body can make better use of iron in meat and calcium in dairy products. As for vitamins, it provides, especially B3, B6 and B9 and also, and a small amount of, the latter two with antioxidant effect.

Soluble fiber and essential oils

Onion is a food that is attributed preventive and / or curative properties because it contains:

• Fiber: which contributes to the regulation of intestinal transit.
• Fructooligosaccharides (FOS): soluble fibers that provide important benefits at the digestive level and have a prebiotic effect, thus stimulating the growth of beneficial intestinal microflora. In addition, they improve intestinal transit, which prevents constipation. These effects also reduce the risk of cancer at the digestive level, improve the absorption of some minerals and possibly influence blood lipid levels, lowering them.
• Vitamin and mineral content.
• Sulfur compounds and flavonoids: provide onions with antioxidant properties. These sulfur compounds are found in volatile essential oils that, upon reaching the respiratory tract, promote expectoration.

How to take it?

Onion is the complement to almost all kinds of cooking and food. It can be eaten cooked, fried or sautéed, or raw, in salads or tapas. It is the base par excellence of stews and stir-fries, it is used in sauces, fried foods, sautéed ... It can accompany well both meat and fish, also in vegetable preparations with other vegetables, even with eggs and dairy products. It can be part of pizzas, empanadas, omelettes, tapas, hamburgers, sandwiches, soups, sausages, croquettes ... It gives a huge game in the kitchen.

Depending on the dish to be made, you have to choose the most suitable type. While white and yellow onions give good results in soups, stir-fries, sautées, and sauces, in softer stews and sauces, red onions give a finer touch due to their sweeter flavor. A less penetrating and more palatable flavor is also achieved for all palates with fresh chives, which will be the best option in salads, tapas and any preparation in which the strong onion flavor is not wanted to stand out.

Why do you cry?

The onion stimulates tearing because it contains highly volatile sulfur compounds that are released when the layers of the bulb that form it are cut. When these compounds reach the mucosa, they cause an irritant effect that produces more tears. To reduce it, try to make clean cuts, for which it is advisable to use knives in good condition and sharp, rather than saw ones. Besides, if the onion is peeled under the tap, it is possible that part of the sulfur compounds go with the water and do not reach the mucous membranes.

Who is it good for and who is not?

Onion may be advisable for the vast majority of the population. However, there are people who do not tolerate it.

It is recommended for:

• Weight control: onion provides few calories and a lot of fiber, which provides a feeling of satiety without hardly contributing to increasing the calories consumed. Therefore, it can be a good complement in weight control diets.
• : the large amount of water and fiber, especially soluble fiber, helps regulate intestinal transit through the formation of less hard and difficult to expel stools. FOS increase the volume of stool and promote evacuation.
• Regulate diuresis: its high content in water and potassium, and the low sodium intake favors diuresis, making it difficult to retain fluids and exerting a purifying role. Therefore, it can be beneficial in cases of hypertension, hyperuricemia and gout, kidney stones, oliguria and fluid retention.
• respiratory problems: the sulfur compounds that give the characteristic spicy flavor come from essential oils that, upon reaching the mucous membranes, favor expectoration at the level of the respiratory tract.

They are not suitable in case of:

• Gastroesophageal reflux: the sulfur compounds that give the characteristic flavor to onions can be indigestible and cause gas. For people with heavy digestions and especially with a tendency to have reflux, onion can be a very heavy food. On the other hand, the way we eat the onion we take raw and fried, they usually generate much more annoyance than if they are taken well cooked as part of a stew for example.
• Flatulence: the amount of fiber contained in the onion can cause excess gas at the digestive level with the consequence of suffering from aerophagia or annoying flatulence.
• Renal insufficiency and / or potassium-controlled diets: sometimes the amount of potassium in the diet should be limited, especially in certain stages of kidney disease. In this case, it is important to control the intake of fruits and vegetables, including onion.

Buying and conservation advice

Apart from choosing the most suitable variety according to the case, firm, hard, without bumps, stains or soft specimens should be chosen. The neck should be short and hard, since the specimens with a soft or long neck are overgrown onions. Onions do not spoil easily unless they are damaged beforehand or stored with excess moisture.

They should be kept in a cool, dry place and preferably protected from light, with the exception of fresh onions, which should be kept in the fridge. Once an onion is opened, if not all of it is used, it is best to cover it with plastic wrap or inside a plastic container and store it in the fridge.

• Season: all year round, although its best time is from the end of March to June.
• Benefits: low in calories, rich in soluble fiber and antioxidant compounds.
• Ideal in: weight loss diets, constipation, fluid retention ...

Diploma in Human Nutrition and Dietetics