1 September 2009

Busting Food Myths with Nicole Senior

Myth: Potatoes are bad for you.

Nicole Senior

: Potatoes are a vegetable, and vegetables are good for you.
The poor old potato is a much maligned food but it really doesn’t deserve all the criticism. It has been called fattening, bad for blood glucose, and generally undesirable, but this really isn’t fair. Spud lovers can relax. Potatoes are good for you.

Potatoes are starchy tubers that grow underground. I remember as a child digging them out of the soil and roasting them whole in an open fire at a friend’s farm – pure joy! They are high in carbohydrate for energy and stimulate that feel-good brain chemical called serotonin. Eating potatoes help you feel that life is good. Potatoes are also a good source of vitamin C and fibre (especially if you eat the skin) and also contain vitamin B6 and potassium.

People often say potatoes are fattening, but this is an exaggeration. Any food containing kilojoules can be fattening if you eat too much, and carbohydrate in potatoes is no more or less fattening than kilojoules from any other source. It is sad for low-carb diets to recommend followers eat mashed cauliflower and pretend it’s potato. Just enjoy a bit of both.

Photo of baby potatoes: Ian Hofstetter

Eaten whole with minimal additions, potatoes are difficult to overeat due to their high ‘satiety index’. Boiled potatoes are one of the most filling foods you can eat. Potatoes cut into French fries and cooked in unhealthy fats are a different story, but don’t tar all potatoes with the same fast food brush. If you are a French-fry (hot chip) fan, then look for establishments that cook them in healthy oil, keep your portions small and skip the salt. This way, you can have your chip and eat it.

Most potatoes have a high GI but even GI Queen Professor Jennie Brand Miller agrees there is no need to ban high GI foods altogether. Just enjoy them in a balanced meal with plenty of other vegetables and some lean protein. There are also lower GI varieties such as canned new potatoes, and varieties such as Almera (GI 65) and Nicola (GI 58). Orange-fleshed sweet potato has a GI of 61. Adding a little healthy fat also lowers the GI, so in fact some nice fat potato wedges roasted in a little olive, sunflower or canola oil is a healthy, lower GI option. Adding vinegar also lowers the glycemic response. To keep potatoes healthy, avoid serving them with butter, cream and cheese.

One of the things I love about the potato, apart from the gorgeous taste and texture, is how simple they are to prepare. I simply wash, cut and microwave on high until tender, and lightly dress with some extra virgin olive oil, dried rosemary and black pepper. Use whatever healthy oils, herbs and spices you like for an instant accompaniment to lean meat, chicken or fish and steamed greens. And a good tip: always cook more than you need because cooled and reheated potato contains a beneficial kind of dietary fibre called resistant starch that keeps your bowel healthy. That’s what I call potato magic.

If you’d like some delicious ideas to enjoy potatoes in sensible portions, check out the new-look http://www.eattobeatcholesterol.com.au/



Wilf said...

You say that potatoes contain vitamin C and other valuable substances "especially if you eat the skin".

True that may be but you should really also mention that the potato must not show any green tinge otherwise the skin does contain toxins. Potatoes should be stored in the dark to avoid the toxin building up - it is usually safer to eat peeled potatoes.

If unaware, read http://en.wikipedia.org/wiki/Potato especially the Toxicity paragraphs.

Anne said...

You mention tinned new potatoes as having moderate GI but I am sure this website has talked about fresh chat potatoes being suitable. Are they? also are chats just baby potatoes or a type on their own? Anne

GI Group said...

The canned new potatoes tested were Edgells Mint Tiny Taters and have a GI of 65. Chat potatoes is a term for immature baby potatoes (or tiny taters). Here's what we have said about potatoes previously in GI News.

"Cutting back on potatoes is something many people on a low GI diet find hard to do. So what’s the answer?

First of all, there’s no need to say ‘no’ to potatoes altogether just because they may have a high GI. They are fat free (when you don’t fry them), nutrient rich and filling. Not every food you eat has to have a low GI. So enjoy them but in moderation.

Secondly, look for the lower GI varieties of potato or serve them in a way that reduces the glycemic response. University of Toronto researchers found that the GI of potatoes ranged from 56 to 89 depending on variety and cooking method (Journal of the American Dietetic Association). Precooking and reheating potatoes or consuming cold cooked potatoes (such as potato salad) reduced the glycemic response. The highest GI values were found in potatoes that were freshly cooked and in instant mashed potatoes. Margareta Leeman and her colleagues at the University of Lund in Sweden found that preparing potatoes the day before and serving them cold as potato salad with a vinegary vinaigrette dressing can lower the GI (European Journal of Clinical Nutrition). In Low GI Eating Made Easy, dietitian Kaye Foster-Powell suggests steaming small new potatoes (with their skin for added nutrients), or bake a jacket potato and add a tasty topping based on low GI beans, chickpeas or corn kernels."

GI Group said...

Hi Wilf,

Nicole suggests eating the skin of healthy potatoes and discarding any potatoes with greening of the skin due to the presence of glycoalkaloids. It’s safer to toss them out than to peel green potatoes she says and has attached some comments on green potatoes from the CSIRO.

The CSIRO says: 'Green potatoes may cause food poisoning and since some of the symptoms are similar to gastroenteritis it is possible that some undiagnosed cases of gastroenteritis have been caused by eating green potatoes. Human and livestock deaths have been recorded as a result of the consumption of greened or damaged potatoes with very high glycoalkaloid levels. It should be noted that glycoalkaloids are not destroyed by cooking processes, even by frying in hot oil. Consequently potatoes with pronounced greening or with signs of damage should not be eaten. It is advisable that green or damaged potatoes are avoided by pregnant women or women who are likely to become pregnant, as there is some evidence of possible foetal damage or loss of the foetus from glycoalkaloid poisoning in animals.'

Unknown said...

Hi, I'm new to this website. Thanks for the great article, really enjoyed it. I'm a firm believer that most food from the earth are good for you, in moderation, especially the lowly potato..I grew up with them and not about to give them up. However I agree, keep them natural. The orange flesh sweet potato is not readily available here in SA, but looking forward to watching it's growing popularity when it finally does arrive. Donna

Olivier PERSIN said...

why do all this logorrhea on consumption of a food that has a high glycemic index ?
the fact to lower its glycemic load is valid for all other starchy foods too, so why not choose, instead, a good starchy ?