NEW YORK • If french fries come from potatoes, and potatoes are a vegetable, and vegetables are good for you, then what is the harm in eating the fries?
Plenty, say experts, including Dr Eric Rimm, a professor in the departments of epidemiology and nutrition at the Harvard T.H. Chan School of Public Health, who called potatoes "starch bombs".
Potatoes rank near the bottom of healthful vegetables and lack the compounds and nutrients found in green leafy vegetables, he said.
If you take a potato, remove its skin (where at least some nutrients are found), cut it, deep-fry the pieces in oil and top it all off with salt, cheese, chilli or gravy, that starch bomb can be turned into a weapon of dietary destruction.
A study last year in The American Journal Of Clinical Nutrition noted that potatoes have a high glycaemic index, which has been linked to an increased risk of obesity, diabetes and cardiovascular disease.
The study found that participants who ate fried potatoes two to three times a week were at a higher risk of mortality compared with those who ate the unfried version.
In the United States, potatoes are the most consumed vegetable, with folk eating an average of 52kg of white potatoes a year. Two-thirds are in the form of french fries, chips and frozen or processed items, the Agriculture Department noted. But fries are undeniably tasty. Here are some better ways to eat them.
EXERCISE PORTION CONTROL
How many fries you eat matters more than things such as the fries' surface area or the type of oil used in making them, said Ms Lindsay Moyer, a senior nutritionist at the Centre for Science in the Public Interest.
Consider, for instance, that a large serving of McDonald's fries is 510 calories, nearly the same as a Big Mac (540 calories), she noted.
The Agriculture Department lists a serving of fries as three ounces or about 85g, which amounts to 12 to 15 individual potato sticks, or about 140 calories.
Split your order, get the smallest portion or substitute with a side salad or some kind of green vegetable, Ms Moyer said. Or get a baked white or sweet potato.
BEWARE OF TOPPINGS AND CONDIMENTS
Some appetisers consist of fries coated with cheese and chilli or other dressings, which can deliver as much as 1,000 calories a serving, Ms Moyer said.
Do not overdo it on the condiments, either. An average packet of ketchup is only 10 calories, but the same amount of mayonnaise can add nearly 100 calories.
Which kinds and cuts are best? Elaine Magee, author of 25 books about healthy cooking, ranks fries best to worst this way:
Homemade baked fries: Make them at a high temperature with a sprinkling of canola or peanut oil.
Home fries: "They tend to still have their skin on as chunked or wedged potatoes, and they aren't deep-fried, but tend to be fried in a skillet, usually in oil," she said.
Sweet potato fries: Magee said they have more vitamin A and fibre.
Then, in descending order, according to Magee: Steak, crinkle-cut and shoestring fries, followed by waffle and curly fries, which are a toss-up because both have a greater surface area to soak up oil.
Chilli cheese fries: These are second to last, but it depends on the kind of fries, chilli ingredients and amount of cheese.
Poutine: "This is an example of taking something with fat and salt (french fries) and topping it with something that adds more fat and saturated fat (cheese curds) and topping that with something that contributes potentially more fat, saturated fat and salt (gravy)," she said.
Diners should ask how often a restaurant changes its oil, Prof Rimm said. The repeated heating, cooling and reuse of oil promotes the creation of fatty acids.
Ms Sharon Zarabi, a dietitian at Lenox Hill Hospital in Manhattan, noted that corn oil, which is often used in making french fries, is high in omega-6 fatty acids, which contribute to inflammation.
Still, Magee said the best defence comes from exercising control.
"Anything can be eaten healthfully if it's eaten mindfully," she said.
"If you eat french fries that way, you will probably be satisfied with 10."