If you’ve been in the diet circle for a while, you know that the number one weight loss rule has always been this: Cut carbs. In the Nineties, the Atkins diet was all the rage – now we’ve got Keto. Both of these popular diets preach low-carb, the apparent weight-loss key. But are there harmful side-effects of switching your side of chips for a tiny garden salad? And are carbs really the waist-expanding enemy we’ve been led to believe they are?
Wait, carbs aren’t a food group?
“Carbs are not a food group on their own. They are a specific type of nutrient found, together with many others, in certain food groups,” says registered dietician Tirsa B Holzhausen, a spokesperson for the Association for Dietetics in South Africa.
There are also many different types of carbs. Think: Glucose; fructose (fruit sugar); lactose (found in dairy); sucrose (table sugar) and amylose or amylopectin (generally known as starch). Another little known, but beneficial, carb is fibre.
Carbohydrates perform five important functions in the body:
1/ They’re a source of energy
The glucose found in carbohydrate-containing foods is used by the body’s cells (especially the cells in the brain) to create energy molecules (known as ATP). These molecules act as fuel for activities in the body. The body can produce ATP from other sources, including fats (the reasoning behind the Keto diet), but glucose is the body’s preferred fuel.
2/ They provide energy to store
When a meal provides more glucose than the body needs immediately to make energy, the excess glucose is converted to glycogen (stored in the liver and muscles). When the glycogen stores are full, the remaining glucose is converted into fat molecules.
Glycogen is essential for healthy functioning because it can quickly be converted back into glucose in situations when the body needs the energy, typically during exercise or starvation (voluntary or not). But when we continuously eat more carbs than the body needs, we end up with excess carbs, which are converted to fat. Bottom line: The body needs some carbs for energy and storage, but too many lead to a fight with the flab.
3/ They save muscle protein
When there’s too little glucose available in the bloodstream, the body makes glucose from glycogen, but when the glycogen stores are depleted, the body breaks down protein in the muscles to create the needed glucose. Over an extended period, this can be dangerous and typically leads to poor strength, poor immunity and a general decline in overall health.
4/ They play an important role in digestive health
While most starches are broken up into glucose (among other things) during digestion, fibre isn’t. The process of digesting fibre provides energy for the ‘good’ bacteria in the gut, which allows them to work optimally in digesting other nutrients. Soluble fibre (found in fruits, veggies and oats) causes water to be drawn into the intestine as they digest, creating a soft stool that’s easy to pass. Insoluble fibre (found in legumes, whole grains, nuts and seeds) provide roughage in the intestine, which stimulates movement and helps to keep us ‘regular.’
5/ It’s important for heart health and blood sugar control
Depending on the type of carbohydrate-containing food, carbs can either benefit your heart health or seriously diminish it. During digestion, fibre binds to bile acids in the intestine and passes through the body; this loss of bile acids stimulates the body to make more, a process which uses cholesterol from the bloodstream.
This cycle lowers cholesterol in the blood, and over a longer period contributes to healthy blood pressure and cholesterol levels, healthy blood vessels, effective functioning of the heart muscle and prevention of atherosclerosis and other heart-related conditions. Eating refined, high sugar carbs will have the opposite effect…
Fibre also slows down the rate at which foods are digested, meaning that all nutrients, including glucose, enter the bloodstream at a slower, more controlled rate and in smaller amounts at a time. This process prevents blood sugar spikes and the fatigued feeling that follows a sugar high. It also provides better insulin-level control and more stable energy levels.
Side effects of cutting out carbs:
Most low-carb diets focus on cutting refined carbs like white bread and pasta, along with sugar and low-fat dairy options. If your body is used to eating these kinds of foods, your body might go through ‘withdrawal symptoms’, which include:
- Low blood sugar symptoms: This can range from feeling light-headed and shaky to experiencing headaches or undergoing mood changes.
- Loss of body protein: This depends on how severely, and for how long, carbs are restricted (zero-carb diets will be a risk factor). Poor health and body function could result from long-term protein breakdown in the body.
- Ketosis: This is the state in which the body burns fat for fuel, which may sound exciting, but over a long period of time it is detrimental to the brain and can lead to mental and physical fatigue, as well as bad breath in the short term.
- Micronutrient shortages: Loss of nutrients such as fibre, vitamin B2, folate, potassium, calcium, magnesium and protein. Lack of minerals could cause muscle cramps in the short term and negatively affect heart health in the long term; lack of fibre could result in constipation and lack of B-vitamins could diminish the body’s energy metabolism, red blood cell production and nerve function.
- Digestive issues: Low-carb usually means high protein or fat intakes. These types of foods could cause diarrhoea or general gastric discomfort if they’re too rich or challenging for the intestine to tolerate. Plus, lack of fibre impairs the intestine’s ability to function optimally, which could worsen the symptoms you’re already experiencing.
How can you include carbs in your diet but still lose weight?
According to Tirsa, including carbs in your diet doesn’t mean eating refined carbs like processed snacks or high-sugar foods like fruit juice. Healthier carbs include:
- Wholegrain starches: Brown rice, quinoa, barley and oats.
- Unrefined foods: Fresh fruit, milk, porridge, rice, potato, sweet potato, dry or tinned peas and beans and popcorn.
- Minimally pre-prepared foods: It’s difficult in our modern-day to avoid all processed foods, but take-away, ready-to-eat and heat-and-eat foods (pasta, pizza, smoothie, freshly-squeezed juice, salad or sandwiches) all usually have a higher sugar content than the version you’d make at home. They’re also usually more processed and served in a bigger portion than your homemade version. By preparing your own meals, you can choose better-quality ingredients and will have more control over the quantities of each ingredient used.
So make “carbs” a small part of a bigger meal…
A large portion of carbs (a big bowl of pasta, three-slice sandwich or burger and chips) will provide way more carbs than your body needs. To avoid eating too many or too few carbs, prepare meals which consist of 25% starch (brown rice, quinoa, barley, sweet potato, porridge or bread); 25% protein (animal or plant-based) and 50% vegetables, which could also include a fruit portion.
Practically, this could look like:
Breakfast: Oats with low-sugar yoghurt and berries or scrambled egg with one slice whole-wheat toast and avocado salsa.
Lunch: Roasted sweet potato and chicken salad with homemade salad dressing or a chicken mayonnaise sandwich with a small side salad and small fruit.
Supper: Grilled fish with savoury brown rice and roasted veg or grilled steak with roasted potato wedges and stir-fried vegetables.
The bottom line
Carbohydrates are essential nutrients which can, and should, form part of any person’s balanced, healthy diet. The question is not whether carbs are good, but rather which types and how much is needed in your individual diet. Visit a registered dietitian in your area for more info about how to include carbs in your diet in a way that will benefit your waistline as well as your long-term health.