In the world of nutrition, potatoes seem to have fallen from grace. Meanwhile, sweet potatoes still — largely — get away scot-free. What is this travesty? Angela Dowden, British award-winning health journalist and Registered Nutritionist examines the evidence in this article published by the American Council on Science and Health.
“Stop cutting out white potatoes – they’re as healthy as sweet ones, dietitians say,” a recent headline in Insider urges us. That gets a big hooray from me.
Forgive my conceit but I cook the best roast potatoes (a British culinary delight) just about anywhere on these shores. Ask my husband.
But the nutrition police don’t approve. According to an article darkly entitled “the problem with potatoes” on the Harvard T.H. Chan School of Public Health website, a cup of potatoes has a similar effect on blood sugar as a can of cola or a handful of jelly beans. Moreover they claim that “this roller-coaster-like effect on blood sugar and insulin can result in people feeling hungry again soon after eating, which may then lead to overeating.”
Wow, that’s quite the set of accusations, especially when sweet potatoes, which have almost identical levels of carbohydrates and calories are often lauded as exemplars of nutritional excellence.
The disdain for standard spuds hinges on the fact that they have a high glycemic index, or GI.
GI measures how rapidly a food increases a person’s blood glucose. A global database of GI values is maintained by Sydney University Glycemic Index Research Services in Sydney, Australia. GI is measured relative to glucose (GI 100) under fixed conditions that don’t relate very much to how we actually eat foods in mealtime combinations.
According to the above mentioned database, sweet potatoes have a GI of anywhere between 44 and 95 depending on the exact variety and method of preparation, whereas a serving of North America’s most popular potato, the Russet Burbank, registers GI values of between 56 and 111. As you can see, there’s not a whole lot of difference between the two.