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Steve Berry > Blog  > The Truth About Low Carb Diets
low carb diet

The Truth About Low Carb Diets

Carbohydrates (carbs) play an important role. They are the primary energy source for the central nervous system and working muscles. They also prevent the breakdown of protein (for energy) and help with the metabolism of fat. Fat is a secondary fuel source. It requires more energy to convert carbs into fat, which is why your body prefers to use carbs as a main source. A good comparison is premium fuel vs standard fuel. Premium fuel helps your engine run at its most efficient, so your car lasts longer and gets more miles in the tank. Standard fuel wastes energy, runs down your engine and reduces the overall lifespan of your car. Think of carbs as your premium fuel and fats as your standard fuel.


There are 3 main types of carbs.

1) Simple carbs, like sugar, white flour and sweets, are broken down into glucose very quickly. These carbs have virtually no nutritional value and should be limited. Eating simple carbs regularly will significantly increase the risk of obesity, diabetes (type 2) and heart disease.

2) Complex carbs (starches), like sweet potato, lentils, oats and quinoa, are broken down into glucose at a slower rate because they take longer to digest. They are rich in fibre, vitamins and minerals, and are unlikely to spike insulin levels or cause weight gain.

3) Fibre comes from grains, fruit, vegetables, nuts and legumes. It cannot be used as energy; however, it helps control blood sugar levels and it can help with weight loss.

A low carb diet will cause your body to burn fat as a main energy source. Sound good? Well it shouldn’t because this is going to lead to a big list of unpleasant side effects and it is not a long-term plan

Your body stores limited amounts of carbs (as glycogen) in your liver and muscle cells. This is so energy is readily available when needed. Most people should have a diet that consists of around 40-60% of carbs from their total calories, depending on how active they are. Consuming more carbs than necessary will cause your body to convert those extra calories into stored fat.


A low carb diet will typically consist of high protein, high fat and, yes you guessed it, low carbs. When you cut out carbs, eventually your body will deplete most carb stores. This will immediately make you look slimmer and appear lighter on the scales. At this stage, your body will have no choice but to use fat as fuel. This requires more energy, so it will result in fatigue, dizziness, hunger, mood swings, constipation (due to less fibre), dehydration, sugar cravings, muscle cramps, sleep deprivation, headaches, hypoglycaemia (low blood sugar), kidney damage (from excess protein) . . . the list goes on. The problem is, as soon as you reintroduce carbs into your diet, your body will store them, causing you to put on weight again.



In conclusion: I tried a low-carb diet for 4 weeks. By week 4 all I wanted to do was sleep all day. I had no energy to train, walk or even read! The moment I started to eat carbs again I felt like I had 20 cans of red bull. There’s a reason why your body uses carbs as a primary energy source. If you want optimised brain and bodily function, then you need to avoid this diet. I believe a diet that is moderate in carbs is much better than a diet that is low in carbs. It’s easy to lose weight on a calorie reduced diet, but that doesn’t mean you should eliminate carbs. Just make sure the majority of carbs you eat are healthy, like vegetables, fruits, legumes and whole grains.