Some of us view carbohydrates as diet enemy number one; others say they’re an essential energy source. So which is it? We asked the experts to sort the wheat from the chaff and give us the facts.
Low-carbohydrate diets are so hot right now — just ask Gwyneth Paltrow, who swears by the health benefits of cutting back on carbs to such a degree that she limits the amount she feeds her children.
Meanwhile, doctors and dietitians are telling us that carbs are essential to a healthy diet. Confused? To find out what’s best for your health and your waistline, keep reading …
Why do I need carbs?
Many people don’t realise that most foods contain some carbs. Vegetables can be a good source, and fibre itself is a carbohydrate. You’ll also find carbs in milk and other dairy products. Sweet foods that contain sugar, even fruit and honey, also contain carbs, because sugar is a carbohydrate.
The energy chain
Carbs are the petrol that fuels the body’s engine. During the digestive process, the body breaks down carbs into glucose, which then moves into the bloodstream. As glucose travels through the body, all of our cells draw on it for energy.
If we don’t eat enough carbs to maintain this steady glucose supply, we force our bodies to start using protein or fat for energy. This is a back-up system that’s designed to see your body through a surprise famine, so it’s a less efficient process.
Glucose is also the main source of energy for the brain, so it’s crucial to our thinking and memory. Plus, without carbs, our muscles lack the energy reserves they need to respond properly to emergencies. So, clearly, carbohydrates are essential to life.
Won’t carbs make me fat?
Fans of low-carbohydrate diets often try to convince us that carbs are fattening, but it doesn’t really matter where kilojoules come from — if we eat more food than our bodies actually need, we will gain weight.
“In fact, carbs are our friends,” says HFG dietitian Zoe Wilson, “and even more so when we’re watching our weight, because gram for gram, carbs provide half the kilojoules of fat.”
“Plus, if we choose wholegrain or ‘brown’ carbs — think brown bread, wholemeal pasta and brown rice — we’re also choosing fibre-rich food, which helps us feel satisfied, too,” she adds.
Guilt by association
The problem is that the word carbs is now a highly loaded term, because people tend to associate it with processed foods. And many desirable carb-rich treats, such as cakes, chocolate, chips and biscuits, also contain a lot of fat — which means they’re loaded with kilojoules, too.
The carbs in these foods come from sugar and white flour. Food manufacturers have stripped this white flour of its fibre, which is key to our feeling full after eating.
“What’s more, this processing also strips the grain of its key vitamins and minerals. So the carbs in sugary cereals, white bread, rice and pasta fail to sustain you,” explains Wilson.
‘‘It’s important for us to realise that low-fibre processed carbs are less satisfying than their wholegrain cousins,” she adds. “This means you’re likely to eat more of them than you would have if they’d contained wholegrain carbs.”
The bottom line
Not all carbs are equal, and we shouldn’t treat them as such. When you’re reaching for carbs, consider the amount of processing the food has had, as well as how rich it is in other nutrients, such as fibre, vitamins and minerals.
What’s the GI factor?
The glycaemic index (GI) is a widely used measure of carbohydrate quality on a scale from 0 to 100. A GI score reflects the rate at which we digest a food as well as the body’s fluctuations in levels of blood glucose after eating it.
If a food scores a high-GI rating (think jelly beans), it means we digest that food quickly. This sends glucose surging into the bloodstream, resulting in a rapid energy hit that puts a strain on our system. Conversely, we digest low-GI foods (think nuts) more slowly, thereby producing a more gradual release of energy.
A food is low GI if it scores less than 55. Low-GI foods help us feel full for longer and help stabilise our mood and energy levels. Many factors affect a food’s GI, including the foods with which we eat it. A plate of high-GI mashed potato, for example, can become low-GI if you enjoy it with a piece of steak, because the steak’s protein slows the digestion and rate at which your body absorbs it.
The bottom line
The glycaemic index is a good indicator of which foods to choose if you want to stabilise blood-sugar levels, but you shouldn’t use it in isolation to make judgements about a food’s overall nutritional worth.
Is there more than a grain of truth to whole grains?
Experts agree that we should include more wholegrain-carbohydrate foods in our daily diet. The word wholegrain is the giveaway here, as these grains — and their nutrients — remain intact.
When manufacturers mill or refine grains, to make white flour, for instance, they extract key parts of the grain’s structure, thereby removing most of its nutrients and fibre. That’s why products made of refined carbs are often called ‘processed’ carbs. But milling whole grains to make wholegrain or wholemeal flour retains all of the grain’s goodness.
Brown versus white
“As a general rule, wholegrain foods (such as rice, wholegrain bread and wholemeal pasta) tend to be brown, whereas products made from processed or refined grains tend to be white,” explains Wilson.
Health professionals advise us to eat grains three to four times a day, meaning with each meal and as one snack. At least half of these grains should be the wholegrain variety.
Eating more whole grains isn’t as challenging as it sounds. Have wholegrain cereal for breakfast, such as muesli or porridge; thenmake a sandwich with grainy bread for lunch; and eat some brown rice or wholemeal pasta at dinner. Snack on grainy crackers with morning tea, and you’ve hit your daily wholegrain target.
The bottom line
There’s no need to completely cut out refined grains, but start eating wholegrain foods every day.
Expand your wholegrain reportoire
Just as oranges are not the only fruit, wheat is not the only grain. Why not enjoy a greater variety of flavours and textures? Take your pick from this wide range of versatile grains…
Amaranth is about 14 per cent protein. It’s best to mix these tiny seeds with other grains; their flavour is strong.
Bake amaranth into breads, pies, cakes and muffins.
Burghul is made from boiled, dried and crushed whole wheat. It’s a staple in Middle Eastern dishes, such as tabouli.
Try burghul in salads or use it as a replacement for rice in pilafs.
Barley is a nutty-tasting source of soluble fibre and selenium, which we need for a healthy immune system.
You can substitute barley for burghul, or add a handful to soups.
Millet is gluten free and high in B vitamins. This grain is popular in Indian recipes, such as pilafs.
Bake with millet, or enjoy it as a cereal in puffed or flaked form.
Buckwheat is often served as a side dish, much like rice. You can buy buckwheat noodles and flour, too.
Make buckwheat porridge for a gluten-free breakfast.
Oats are one of the most popular whole grains, and they’re a great source of soluble fibre.
Try oats in smoothies, bread and bakes (not just porridge!).
Quinoa is a complete protein; it contains all eight essential amino acids. It’s gluten free, too.
Use it as an alternative to rice, and in stuffings and salads.
Rye is a common ingredient in bread. Naturally lower in gluten than wheat is, rye produces chewier loaves.
Use rye to make your own bread, or simply buy rye bread.
Brown rice is higher in fibre than white rice is. And all varieties of rice are gluten free.
Brown rice is great in sushi, or as a side with stir-fries and curries.
Spelt is higher in protein than wheat is. It’s also a good source of vitamin B2, which our bodies need for energy.
Substitute spelt for rice in risottos, or toss it into your salads.
Wheat is the other hugely popular grain. It’s a component of flour, bread, baked goods and pasta.
For the greatest health benefits, choose wholegrain varieties.
Why choose whole grains?
Wholegrain foods are your best carbohydrate choice. They’re brimming with fibre, protein, B vitamins, minerals and antioxidants. Make three of your four daily carbohydrate serves wholegrain, and you’ll reap these rewards.
Better heart health: Enjoy lower blood cholesterol and a 30–48 per cent lower risk of heart disease. A diet rich in wholegrains can also lower blood pressure and slash your stroke risk by up to 30 per cent.
Weight control: Studies show that people who eat a wholegrain-rich diet find it a lot easier to control their weight.
Better bowel health: You’ll reduce your risk of bowel cancer.
Reduced risk of diabetes: Your chance of developing type 2 diabetes will drop significantly, by 21–33 per cent.
Stave off asthma: Eat a diet high in whole grains, and you’ll decrease your risk of asthma.
Good carb, bad carb — what’s the verdict?
Carb-rich foods form the basis of a healthy diet. We all want to boost our energy levels, preserve brainpower and maintain good general health. “We can do this by regularly eating the right carbs,” says Wilson. “The evidence so far suggests we limit our intake of refined carbohydrates (which are often laden with sugar) and increase our consumption of foods that contain unrefined carbs, such as whole grains, starchy vegies, fruit, beans and dairy,” she adds. “This will give you the greatest heart-health and weight-loss rewards.”
A healthy awareness
To get an accurate picture of the kinds of carbs you’re eating, keep a food diary for a few days.
“Recording your habits will help you to cut some of the sugary and processed carbs from your diet, and to boost your intake of fibre-rich carbs and whole grains. And if you’re trying to lose weight, measure your portions; it’s easy to underestimate the amount you’re really eating,” says Wilson.
“For foods such as rice, pasta, couscous and breakfast cereal, a serve the size of your fist is a good general guide to a healthy amount. Make a rough appraisal, then relax and enjoy eating carbs — just keep an eye on your portions.”
The bottom line
Choose unprocessed carbs, and limit any carbohydrate foods that are also high in saturated fat, salt and sugar.
Is it a question of timing?
Some people believe that forgoing carbs after 5pm helps them lose weight, because the body turns these carbs into fat while we’re sleeping. But there’s no scientific evidence to back this claim.
If you’re an early-bird exerciser, eating carbs at night is essential. In the morning, your muscles will rely on the glucose from the carbs you ate the night before, so without them, you’ll have no ready form of energy to use. You’ll feel fatigued and end up burning fewer kilojoules during your fitness session, which is the exact opposite of what you want!
The bottom line
Any rewards that result from cutting carbs at dinner have more to do with your eating fewer kilojoules as a result. And doing that is what’s really going to help you lose weight.
Is there any truth to the Atkins diet?
When the Atkins diet found fame as a weight-loss wonder, it also popularised the notion that a low-carbohydrate, high-protein diet was the way to go. But this misguided belief fuelled much confusion about carbs, and it still does today.
“Before Atkins came along, people thought they could lose weight by eating a high-fibre, low-fat diet,” says Wilson. “So when this well-known diet grabbed our attention, there was a complete turnaround in our weight-loss ‘wisdom’.”
Atkins based his diet on the premise that limiting carbs forces your body into ketosis — a process in which your body stops using glucose for energy and starts extracting energy from your fat stores. When this happens, you lose weight, but much of it is water (which the body stores, attached to glucose, in your muscles).
Atkins also claimed that the body needs to burn more kilojoules to shed fat, thereby increasing weight loss even further. (Studies later disproved this, linking weight loss to a lower overall kilojoule intake.)
The hidden key
“We know that protein helps us feel full, so it’s fair to say that it also makes us less likely to overeat,” says Wilson. “But if you ban a whole food group, such as carbs, you’re both restricting your kilojoules and missing the delicious spread you might have enjoyed on toast, or the satisfying fat in which you may have baked your roast potatoes.”
And the Atkins approach to eating wasn’t balanced either. “Atkins is a dull way to eat and a difficult diet to sustain, so its followers regained the weight.
“Extreme low-carb diets also leave little room for fruit, vegies and whole grains, all of which are essential to a balanced diet,” says Wilson.
“Although some studies show that low-carb diets can reduce blood-fat levels and decrease insulin resistance, there is stronger evidence to support the benefits of eating carbohydrates,” adds Wilson.
The bottom line
For lasting and sustainable weight control, fill a quarter of your plate with low-GI carbohydrates — and leave the high-GI processed stuff on the shelf.
How many carbs do I need?
Aim for four or more serves every day. One serve is: