Onions belong to the allium family of plants, which includes garlic and leeks. These vegetables have characteristic pungent flavours and some medicinal properties.

Onions vary in size, shape, colour and flavour. The most common types are red, yellow, and white onions.

The taste of these vegetables can range from sweet and juicy, sharp to spicy. In most cases, they complement most dishes.

One can use raw chopped onion in a sandwich filling or as a salad topping. This vegetable also makes a tasty addition to dips.

According to nutritionists, these flavourful bulbs are packed with numerous nutrients and are healthy whether raw or cooked, though raw onions have higher levels of organic sulfur compounds that provide many benefits.

Erick Musengimana, a nutritionist at Rwanda Diabetes Association, Kigali says including onions in a dish is a great way to boost the flavour without adding calories, fat or sodium.

He says onions are excellent sources of vitamin C, sulphuric compounds, flavonoids and phytochemicals.

Phytochemicals or phytonutrients are naturally occurring compounds in fruits and vegetables that are able to react with the human body to trigger healthy reactions.

Besides, Musengimana says their high levels of antioxidants give onions their distinctive sweetness and aroma, adding that foods that are high in antioxidants and amino acids allow one’s body to function optimally.

He goes on to note that onions are low in calories (45 per serving), very low in sodium and contain no fat or cholesterol.

Furthermore, he says onions contain fibre and folic acid, vitamin B that helps the body make healthy new cells. 

"Red onions contain a higher amount of antioxidants and flavonoids than the yellow or white onion and they are a rich source of quercetin,” he says. 

Quercetin is a powerful antioxidant with anti-inflammatory properties that may help fight chronic diseases such as heart disease and cancer, and it is beneficial in eliminating free radicals in the body. 

It may also prevent the release of histamine, making onions a natural antihistamine. 

Fights diseases

Musengimana says consuming onions has been linked to reducing the risk of several types of cancer, improving mood and maintaining skin and healthy hair.

Studies have shown that allium vegetables extensively important prevention of cancer, especially stomach and colorectal cancers.

Additionally, nutritionists say consumption of onions helps in reducing the symptoms of bladder infections, promoting prostate health and lowering blood pressure.

Other important phytochemicals in onions are disulfides and copaene; these are all helpful in maintaining good health and have anticancer and antimicrobial properties.

Musengimana explains that the polyphenols in onions act as antioxidants, protecting the body against free radicals.

"Eliminating free radicals can help encourage a strong immune system. Also, the quercetin in onions helps reduce allergic reactions by stopping your body from producing histamines-which are what make one sneeze, cry, and itch if you are having an allergic reaction,” he says.

Several studies have also found out that intake of allium vegetables, including onions, are associated with reduced gastric cancer risk.

In fact, it has been proven that eating between one and seven servings of onions per week may help reduce the risk of colorectal, laryngeal, and ovarian cancer.

Whereas, eating several servings of onions a day may help decrease the risk of oral and oesophageal cancer.

mbslydia31@gmail.com