Cooking spaghetti al dente and mashing spuds with the skins on make them less unhealthy - even beneficial, explains Sophie Morris
Ben made grated tomato sauce for our spaghetti
When you hear the words “good carbs”, you know that we are probably not talking about a bag of chips lathered in cooking oil and salt and vinegar. But new findings on what is and isn’t “healthy” in the world of carbohydrates is cause for celebration, especially if you are a pasta fiend.
Pasta is one of the world’s most popular foods but spaghetti, penne et al have long been smeared with the “unhealthy” label. As a starchy, processed carbohydrate made with wheat flour, pasta is said to give us energy spikes but little else in the way of fibre or nutrients, and is also blamed for making us put on weight.
But now nutrition scientists at the University of Minnesota are claiming the opposite, claiming that “pasta does not hinder weight loss or contribute to weight gain”. What’s more, the authors of the new research, Lisa Sanders and Professor Joanne Slavin, writing in the journal Nutrients, say that pasta can benefit gut health and even help with weight loss.
Their review also demonstrates some surprising findings, especially if you are looking to fill your diet with good carbs. These include how a food’s structure and our body’s capacity to digest it can change depending on how it has been cooked and its temperature when eaten.
Even white pasta can be good We are often told to eat wholemeal or wholegrain versions of our favourite grains and flours, but Sanders and Slavin banned wholegrain, gluten-free and addedprotein pasta from the 38 studies they reviewed. They also excluded egg or rice noodles, to make sure that the data they were looking at concerned white pasta alone.
The studies all investigated pasta consumption and weight, and found that “pasta is either inversely or not associated with overweight or obesity in healthy children and adults, and does not contribute to weight gain within the context of a healthy diet.”
Low GI carbs Even though pasta looks like a processed product and is made from refined wheat, it has a much lower GI - glycaemic index - than other refined carbs such as breakfast cereals. Surprisingly, white pasta has a GI of only 50-55, compared with 100 for a slice of white bread. Foods with a high GI cause spikes and falls in blood sugar; too many of these over time will reduce the efficiency of your body’s ability to release insulin and absorb sugar from the bloodstream, which will instead be stored as fat and can lead to type 2 diabetes.
“Unlike many other refined grains,” explains Sanders, “the unique structure of pasta makes it a low-glycaemic index carbohydrate. Low GI-load diets have been shown to be beneficial for weight loss or maintenance, even when the low GI diet includes pasta.”
Food with a GI of 55 or less is considered low. Other carbs in this group include beans, pulses, brown rice, porridge oats (not instant porridge), and bulgur wheat.
Don’t overcook it One of the most surprising outcomes of the study is how significantly cooking and heat affect GI. The advice is to not overcook pasta, in order to slow down digestion. We know dried pasta is inedible, but cook it al dente (firm not falling apart) and it will retain some of what is known as “resistant starch”. Our bodies struggle to break down and digest this resistant starch, and the slower release will have a steadier effect on our blood-sugar levels.
Eat chilled Pasta salads are divisive. If you are a hater, maybe the discovery that chilled pasta is better for you will make you rethink. Once pasta cools down, its carbs partly return to their resistant-starch structure (think al dente). This means the GI goes down as the pasta chills, and this occurs even if you overcooked it in the first place.
This is where your gut health gets a look in, because the resistant starch can provide nourishment for gut microbes, encouraging them to flourish and improve your gut fauna.
Even reheating brings benefits Do you like your pasta piping hot? Dr Tracey Robertson, a nutritional scientist at the University of Surrey, looked at how blood sugar behaves when pasta is eaten just after being cooked, after cooling, or once cooled and reheated.
The meals were identical - pasta with olive oil and a tomato sauce. Her study, published in the European Journal of Clinical Nutrition, found that the best result - ie smallest rise in blood sugar - occurred when the pasta was cooked, chilled, then heated up again.
Potato power Lowly spuds are also often criticised as an unhealthy food, when in fact they are packed full of nutrients. A 100g portion supplies a third of our daily vitamin C, 12 per cent of the recommended amount of potassium (which controls blood pressure), and 8 per cent of our dietary fibre.
And you don’t have to eat it plain - mashing a potato with olive oil and butter will reduce its overall GI, which for an average white boiled potato is 83, but that comes down when you eat the skin and combine it with fats and protein.
Want to bring that GI down even lower? A study into the effects of glycaemic index with a focus on potatoes, published last year in the journal Foods, found that a boiled red potato with a GI of 89 reduced to 56 once chilled.
Mix and match As with everything we eat, portion size plays its part, but what we eat with our pasta is also significant. As delicious as it is, a lasagne made with a fatty ragu, bechamel and cheese will add a lot of calories to your meal compared with a homemade tomato and vegetable based sauce. Adding oily fish such as tuna or sardines is a good way to add protein, which will help you feel full for longer.
Even juice can be healthy There are many different kinds of carbs, and fruit juice is another that is often under fire. However a study in the journal Plos One last week suggested that a small glass of OJ a day can help to lower blood pressure.
While eating the whole fruit is a better option, because of the fibre, oranges in any form are full of vitamin C and have antiinflammatory properties. It was also found that juice does not spike blood sugar in the same way as drinks with added sugar do.