A scientist specialising in long life has shared a superfood that he says is cheap, easy to find, and can help you live longer. Dan Buettner researches ‘blue zones’ – parts of the world where people live for much longer than average and have fewer chronic illnesses.
There are five of them – Okinawa in Japan, Sardinia in Italy, Nicoya in Costa Rica, Ikaria in Greece, and Loma Linda in the US. It is thought that physical activity, low stress, rich social interactions, a local whole foods diet, and low disease incidence all contribute to people in those locations living far longer than usual.
Buettner has spent years researching both the lifestyle and diet of people in these zones, and he gave his advice on a particular superfood which he feels can help others live longer. He said that one specific food people on the Japanese island of Okinawa eat can have a massive health impact:
“I’m going to show you the one longevity superfood that everybody can afford – sweet potato,” he said. “Want to live longer? Eat more sweet potatoes.
“Ideally it would be a purple sweet potato from Okinawa but regular sweet potatoes are just fine. They’re full of complex carbohydrates, they have protein, they’re cheap, they taste delicious, and they’re full of micronutrients.
“Okinawans—one of the longest-lived populations on Earth—get over 60 per cent of their daily calories from these vibrant, nutrient-packed tubers. They’re loaded with complex carbs for sustained energy, fibre for gut health, and antioxidants to fight inflammation. Forget the latest diet trend—longevity is built on simple, whole foods like this.”
Why sweet potatoes?
It is well-known that sweet potatoes are packed with healthy vitamins and nutrients. Not only are they a rich source of fibre – something more than 90 per cent of Brits do not eat enough of – but the antioxidants also improve digestion and reduce the risk of diabetes and colon cancer.
They are also recommended for diabetes patients because they do not cause any spike in blood sugar levels. Sweet potato is a complex carbohydrate and has a low glycemic index. It takes longer to digest compared to simple carbohydrates and makes you feel fuller for longer, making them a great weight-loss tool.
Their antioxidants like vitamin C, carotenoids, and phenylpropanoids have anti-inflammatory properties and protect against inflammatory conditions like arthritis. They also contain polyphenolic compounds that are good for eye and retinal health. The vitamin A in sweet potatoes not only keeps your vision healthy but also boosts your immune system. A single sweet potato provides 102 per cent of your body’s vitamin A requirement.
Sweet potatoes are rich in vitamin B6, which synthesises serotonin, a neurotransmitter that regulates mood. They also contain anthocyanin, which helps in improving memory. They are also rich in vitamin C, which boosts collagen production preventing premature ageing and keeps your skin glowing.
The purple sweet potatoes that Buettner referred to tend to be starchier and tougher than the more orange ones we have in the UK, meaning they take longer to cook. Anthocyanins – an antioxidant found in the likes of blueberries and blackberries – give it its deeper colour.
Anthocyanins have been linked with anti-inflammatory and anti-cancer properties, while the antioxidants in the purple variety of sweet potato also lower the risk of cancer. They are also thought to reduce the risk of high blood pressure.