Most people will be familiar with the classic yellow banana. It’s a common sight in supermarket aisles and household fruit bowls alike.
But, did you know that bananas have different health benefits depending on the colour of their skin? Usually, people wanting a tasty and nutritious snack will buy greener bananas and wait a few days for them to mature to their well-known yellow tone.
These unripe bananas offer some surprising benefits for anyone with diabetes. Dr Karan Rajan, an NHS surgeon, explained that each stage of ripening offers “a completely different nutritional profile” – with a typical banana going through three main phases.
The more under-ripe or green banana is a “resistant starch powerhouse”. This fuels your gut microbiome like any other prebiotic would because it reaches the large intestine mostly undigested and promotes a healthy gut lining and overall digestive function.
Snacking on these greener versions is also helpful if you’re managing high blood sugar. Dr Rajan said: “It’s low in sugar (only 10g compared to 17g in a standard yellow banana), which is useful if you’re keeping a close eye on this.”
As bananas start to ripen, they lose fibre but make up for this by increasing the level of potassium per fruit. At these middle stages, bananas also start to become softer and “mildly sweeter” to eat, says Dr Rajan.
Potassium is a mineral that helps control the balance of fluids in the body and also helps the heart muscle work properly. Adults (19 to 64 years) need around 3,500mg of potassium a day, which may seem high, but a single banana could have about 360mg each, making them a good and balanced way to boost your intake.
However, the classic yellow fruit does have more antioxidants, claims Dr Rajan. Bananas contain specific ones called catechins that may help protect against heart disease and cancer. Experts stress that banana peels contain more catechins than the pulp, so it might be worth doing something with the skin rather than throwing it away.
It’s also packed with vitamin C and B5, making it “easy to digest”. Dr Rajan explained: “Most of that resistant starch is now converted to simple sugars, meaning faster energy absorption.” This makes it a perfect snack if you plan on exercising or want something naturally sweet as a treat.
As bananas reach the stage where people typically throw them in the bin, overripe bananas certainly have some benefits. The sugar levels increase to around 17g per fruit, meaning you get a “quick hit” that’s useful for a quick pick-me-up.
The fruits that develop ‘dark spots’ are also highest in helpful antioxidants. You don’t have to eat them raw to get the benefits, as Dr Rajan suggests whipping up a healthy banana bread loaf or blitzing them into a smoothie.
Bananas are fairly cheap to buy and handy to keep around the kitchen for a quick and convenient snack. A bunch of five currently costs less than 80p in Aldi.
