Guide to Carbohydrates

High-carb, low-carb, carb, carb, carb! Few four-letter words have excited so much controversy. Carbs (aka carbohydrates) have been revered and vilified. Some doctors and nutritionists view them as key to an excellent diet; others blame them for a host of ills, such as weight gain, metabolic syndrome, adult-onset diabetes, heart disease and cancers. The real issue is this: do you eat good carbs or bad carbs? Your answer makes all the difference.

At a glance… 

 

GooDies

Goodies are veggies and fruits that are not too starchy, not too sweet, and preferably organically grown.

  • Non-starchy vegetables e.g. leafy greens, broccoli, cauliflower, onions, leeks, garlic, herbs, young carrots, peppers, tomatoes, courgettes, squashes, aubergines, cucumbers, bean sprouts, asparagus
  • Berries e.g. blueberries, raspberries, strawberries, blackberries
  • Lemons and limes e.g. straight-up lemons and limes, Meyer lemons
  • Pulses e.g. lentils, split peas, butter beans, broad beans, haricot beans, flageolet beans, black beans
  • Home-made vegetable juices

GooDie s in moderation… 

These are starchier or sweeter natural foods, minimally processed and preferably organically grown.

  • Starchy vegetables e.g. parsnips, yams, sweet potatoes, older carrots, fresh sweetcorn
  • Sweeter fruits e.g. apples, pears, bananas, dates, oranges, mandarins, peaches, nectarine, grapes
  • Whole, non-milled grains and 'seed' grains e.g. whole wheat berries, spelt, Gruenkern, kamut, rye, barley, oat groats, brown rice, wild rice, buckwheat, millet, quinoa, amaranth, corn
  • Whole, coarsely milled grains e.g. sourdough rye bread, whole wheat pasta, rolled oats, flaked grains
  • Potatoes steamed or baked in their skins
  • Unpasteurised honey (e.g. high-quality Manuka, local honeys, such as Tara Hill or Mount Anville) (NB Never give any honey to babies or small toddlers; they risk infant botulism)
  • Home-made fruit juices, preferably diluted

  BaDDieS

  • Commercial fruit juices
  • Refined, baked goods, e.g. doughnuts, pastries, sausage rolls, cakes, biscuits
  • White grains & grain products e.g. cereals, white rice, white pasta, white bread, commercial corn chips
  • Finely milled wholegrain products e.g. 'wholegrain' versions of the above, commercial 'brown' bread, instant oatmeal
  • Refined potato products e.g. chips, wedges, crisps, snacks
  • Processed and junk foods e.g. fast food, TV dinners
  • Sodas, sweets, glazes, sauces, syrups (including agave)

 What are carbohydrates?

Plants make carbohydrates via photosynthesis, which converts solar energy into chemical energy for storage. The sugar molecule (carbon + hydrogen + oxygen) is the basic building block of all carbohydrates: sugars, starches and fibres. Starches and fibres are simply strings of sugar molecules, arranged in different ways to create different substances. So, peach fructose, potato starch and bamboo fibre are all carbohydrates, as is the booze in your pint.

All plant foods contain carbohydrate. Dairy products contain lactose and honey contains fructose. Every human cell needs glucose for energy. Glucose is a single-unit sugar. We get it from plant foods, either directly or by breaking down bigger sugars and starches. We need to absorb glucose slowly, so nature pairs sugar with fibre, such as the insoluble fibre in leafy greens, soluble fibre in apple pectin and resistant starch in beans. Fibre regulates sugar flow and prevents constipation. Whole plant foods also contain micro-nutrients: the vitamins, minerals, enzymes and plant chemicals the body needs for biochemical reactions. By eating a wide variety of plant foods, we get water, protein, fats, fibre and micro-nutrients for only 4kcal per gram of carbohydrate. Not bad!

Caveats

  •  Intolerances and allergies to gluten in grains, lectins in legumes, lactose in milk, certain fruits and vegetables, etc.
  • Some starches, such as potato starch and finely milled grains, are converted to glucose too fast for the body to handle
  • Fructose is the sweet-tasting sugar in plants. If too much is eaten at once, the liver converts it to fat. Table sugar and high fructose corn syrup are the common culprits but fruit juice and overeating fruit can do it too.
  • Actylamide is formed when starchy foods are cooked on high heat without water (e.g. baked, grilled, fried). In high doses, acrylamide causes cancer in some laboratory animals. The jury is out regarding humans.

The Human Lab

If carbohydrates are Good Guys, why do they promote obesity, metabolic syndrome, adult-onset diabetes, cardiovascular disease, cancers and other illnesses? Because… our sticky fingerprints are all over this food group. What does 'carbs' call to mind? Strawberries and cucumbers? In a glass of Pimm's, perhaps. More likely, it conjures up chocolate croissants, crusty bread, chips, pasta, sausage rolls … all those lip-smackin' things that taste dee-vine with an ice-cold beer. Then you have sweeties, sodas, sauces, syrups and other carbs cooked up in the human lab. Enter <stage left> foods made in a plant. The Baddies of CarbWorld, promoters of ill-health!

Metabolic roller-coaster

These evildoers throw spanners in our metabolic works. Processed carbs are finely milled, heavy on starch and laden with sugar: a recipe for disaster. They contain practically no fibre, water, or micronutrients, so concentrated sugars hit the body without the buffer of fibre and in greater quantity. When we eat fruit and veg, the pancreas releases the hormone insulin, which 'escorts' glucose into our cells to be burnt for energy. Excess glucose is converted to glycogen (the animal storage form of glucose) and stored in our liver and muscle cells. Glycogen can be re-converted to glucose as needed. Say we eat pizza and ice cream, though. The starchy dough is broken down into glucose. Sugar (glucose + fructose) is split into its respective parts. The sudden rise in blood glucose triggers insulin release. Insulin sweeps through the body, sucking up glucose and storing the excess as glycogen or, if the glycogen cupboard is full, fat. Our blood sugar drops and we feel peckish again, so we eat cake. The same thing happens. Over time, the process can blunt our cells' sensitivity to insulin, leading to insulin resistance and a metabolic roller-coaster. Not a funfair!

Meanwhile, fructose is also giving grief. The liver metabolises fructose. In natural foods, fibre slows down fructose absorption. Sugar contains concentrated fructose and no fibre. It is a quantity issue: the liver cannot cope with the fructose rush. It has no pathway to turn it into glycogen but it does have a pathway to turn it into fat … a form of fat that is bad for the heart. So, a high-bad-carb diet is de facto a high-fat diet, implicated in obesity, insulin resistance, metabolic syndrome, diabetes type 2, high blood pressure, heart disease, cancer, Alzheimer's and other 'diseases of civilisation'.

Final word

Don't avoid carbohydrates, as some low-carb dieters advocate; just bin the baddies! Good carbohydrates not only nourish the body; when eaten instead of bad carbs, they help to address the issues caused by the latter. Just choose wisely and eat real food!

As Michael Pollan puts it in Food Rules: 'If it's a plant, eat it. If it was made in a plant, don't.'

Did you know? Raw food chefs are skilled at making good carbs taste really good! Check out Jennifer Cornbleet, Mimi Kirk and Russell James for starters.      

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