This question - and highly debated topic - has engrained itself (pun intended) in the health and fitness industry in recent years. It's also a question that seems to evoke expert opinions faster than the insulin spike of your morning breakfast juice.
Why? I put it down to the fact that 99.9% of people have probably tried the no-to-low carb thing at some stage, right? And since we've experienced it, we're now experts? Wrong. So let's clear a few things up, shall we?
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What are carbs?
All carbohydrates are formed from carbon, hydrogen and oxygen, but in different ways. There are three main types of carbs - monosaccharides, disaccahrides and polysaccharides.
Monosaccharides are simple sugars, including glucose, galactose and fructose. These are a basic form of carbohydrate, and cannot be broken down any further. Disaccharides are two monosaccharides joined together, and include sucrose, lactose and maltose. Polysaccharides are many monosaccharides joined together, such as amylose and amylopectin. You also have oligosaccharides which are smaller polysaccharides, but it's just easier to group these two together.
What do they do?
The low-carb brigade claim you don't "need" carbs as your body can make them through a process called gluconeogenesis - converting proteins or fats into glucose and glycogen to be used by the body. Although true, gluconeogenesis demands a lot of energy and isn't very efficient, which is why so many of us feel like literally murdering someone when starting down the low-carb path.
The main things carbs do is provide you with a quick and easy source of energy. Your body requires this energy -in the form of glucose and glycogen for almost any activity, particularly high-intensity exercise. So carbs can play a critical part in ensuring you perform at your best during your workouts, whilst also aiding your recovery process.
Why do carbs get such a bad rap?
It comes down to two main points:
1. Weight loss
If you cut carbs, you're very likely to lose weight, fast. And here's why:
WATER: For every gram carbohydrate you store in a cell, your body will store three grams of water to help maintain it. So when you start to deplete the carbs, your body won't require the excess water, so you'll quickly shed weight. But, let's be clear: weight loss is not fat loss! You may have lost weight on the scale but it's only water! Check out my article for a little more info.
YOU CONSUME LESS CALORIES: Carbs are classified as a macronutrient, the others being proteins and fats. So, when you cut them, you're basically cutting a whole macronutrient and therefore the associated calories that comes with them. So, you're eating less and losing weight - crazy right!
Insulin is a hormone often referred to in regard to diabetes, as people with diabetes either don't produce insulin at all (type 1 diabetes) or they produce so much insulin over a period of time their insulin receptors shut down (type 2 diabetes).
It's this second condition that is often associated with a long-term, high carbohydrate diet. However, it must be clearly stressed that carb intake is far from being the only factor involved in developing type 2 diabetes. Being overweight, inactive, having a generally unhealthy diet, and getting a large amount of your calorie intake from sugars and fats, all contribute to type 2.
Even in non-diabetics there are still those who dislike carbs. The reason being, insulin is a "storage" hormone. When you eat carbs, your body releases insulin to help take the carbs to be used for energy, or to be stored in the liver or muscle cells. Due to this storing effect, high levels of insulin are often associated with fat storage.
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Bring back the carbs!
It ain't all bad news though. For a start, the effect of elevated insulin is only really relevant if you're eating carbohydrates by themselves. As soon as you add protein, fibre, or even certain types of fat to a meal, you dampen the insulin response and your blood sugar rises at a much slower rate.
Secondly, if you're eating in a calorie deficit (i.e. consuming less calories than you expend) then whilst insulin may be a storage hormone, there are no extra calories for it to store as fat - so even if it's looking for something to store, it won't find it.
It's all individual
Generally speaking, leaner people who carry more muscle mass will have better insulin sensitivity, meaning they can eat more carbohydrate while still losing fat - or at least staying lean. Also, sorry ladies, but guys are generally able to consume more carbs that you. Yes, yes, I know - it's not fair!
If you're a little older, carrying a bit more fat than you'd like, or with a history of yo-yo dieting and changing body shapes, you may need to keep your carbs a little lower to help restore some insulin sensitivity. The good news is that you don't have to cut your carbs to absolute zero to drop body fat - it's all about moderation and sticking to a few guidelines.
The carb guidelines
1. Earn your carbs - If you don't expend a lot of energy, you don't deserve them. As a general rule, the more active you are, the more carb-goodness you've earned.
2. Choose quality sources - Most of your carbs should come from nutrient-dense sources, such as fruits and vegies, beans and pulses and wholegrains.
3. Get your fibre in - Make around 10-20 per cent of your carbohydrate intake fibrous. So if you eat 200 grams of carbs per day, look to get between 20 and 40 grams of fibre.
4. Carbohydrate timing - Consuming some carbs before exercise may help with performance, and within a couple of hours of ending training can also aid in recovery. Generally, the closer to your training time, the better off you'll be.
5. First things first - When eating your meals, focus on consuming the protein and fat sources first and finishing with carbs. Remember, carbs are just a bonus.
6. Don't consume carbs alone - They should always have protein and/or fat around to ensure your blood sugar level doesn't spike.
And lastly, remember this: at the end of the day, if going low-carb gives you a lean body but leaves you without energy or the will to live, is it really even worth it?