Many people like to just eat onions and blend onion with various foods without knowing their attributes, nutritional composition and which one gives the most health benefits. Many think these onions only differ in colour and taste – but no, they are different in terms of the health benefits and other beneficial compounds they provide.
These onion types are all powerful superfoods that come with anti-carcinogenic, antiviral, antibacterial, and antioxidant properties. All these are beneficial to our body but which one has the most in terms of these benefits.
All these types of onion have been found to be low on the glycemic index (how much sugar they add to our blood), with a rating of 10. They provide about 10 percent of the daily value for vitamin C and the same amount of calcium per serving.
Differences in Health & Nutritional Benefits of Red, White & Yellow Onions
The red onion has about 2 grams of fiber per 100-gram serving. This is slightly a better source of fiber when compared to the white onion which contains about 1.2 grams of fiber in the same serving. Both are not particularly high sources of fiber.
Difference In Antioxidant Properties
From the colour of the red onion, it is easier to predict that they contain higher amount of flavonols. These compounds called flavonols have antioxidant properties. Red onions contain 415 to 1917 mg of flavonols compared to yellow ones, which only contain 270 to 1187 mg.
Red onions have higher flavonols, than yellow onions, which in turn have higher flavonols that white onions. The flavonols are more concentrated in the outer and redder layer of the onion. Therefore, when you peel your onion, don’t do so deep into the outer red layer of the onion.
Another important compound present in red onions is quercetin – a polyphenol compound. It helps in getting rid of free radicals. This compound is present in white onions too, but a lot more in the red type.
Difference In How They Help Fight Cancer
Since the red onions have higher level of antioxidants in them than the white and yellow types, they (the red onions) provide higher protection against cancer.
As mentioned earlier in this article, red onions contain higher level of quercetin. This quercetin, with allicin in red onions has been shown to reduce inflammation and be beneficial for both the prevention and treatment of cancer.
A particular study has shown that the risk of stomach cancer was reduced by 50% when half an onion was eaten daily. Other studies have also shown that eating onions reduces the risk of stomach, colorectal, oral, laryngeal, esophageal and ovarian cancer.
Final verdict on choosing onions…
As has been said earlier, don’t over-peel onions. This way, you get the best nutritional and health benefits from them. Most of these compounds that give these health benefits are more concentrated in the outer layers of onion.
According to a particular study, peeling the first two layers of the onion removes 75% of the antioxidant anthocyanins. So, you might want to simmer down on cutting those outer layers of your onions.