Are Carbs Bad For You?

A range of healthy carbs
(Image credit: Shutterstock)

If you’re embarking on a health kick and casting around for advice, one of the first bits of diet advice you’re likely to receive is to reduce the amount of carbs you eat (a low-carb diet), or even remove carbs from your diet entirely (a ketogenic diet). It’s not an entirely unreasonable move, especially considering many of us overindulge in certain delicious carb-heavy and calorific foods like chips, but it is also true to say that carbs take more than their fair share of the blame when it comes to people being overweight.

To find out why we need carbs and how you can adjust your intake of them to be more healthy, we spoke to dietitian Richard Chessor, speaking on behalf of the British Dietetic Association, who’s also a SENr sports exercise nutritionist.

Why do we need carbs in our diet?

Carbs are the body’s preferred energy source. Our brain and muscles tend to use carbs to supply the energy we need to function and as the intensity of that function increases, for example during exercise, the more we rely on carbs for energy.

Is cutting carbs a good way to lose weight?

It can be. Each gram of carbohydrate provides approximately 4kcal [four calories] therefore by decreasing our carbohydrate intake we can decrease our total calorie intake to create a negative energy balance and the outcome is weight loss.

However, removing too much carbohydrate from your diet could result in tiredness, decreased cognitive function and compromised exercise performance. Therefore, restricting carbs for weight loss should be balanced between the energy provided from the other macronutrients in our diet – fat and protein – and our requirement for carbohydrate to remain functioning effectively.

How much carbohydrate should you eat each day?

This entirely depends on your daily activity level. Those engaging in frequent high-intensity exercise may require 6-8g per kilo of body mass per day. So for a 75kg person this would mean 450-600g per day. Those with a more sedentary lifestyle may only require 2-3g per kg per day – for a 75kg person this would mean 150-225g per day.

In the UK, the Dietary Reference Value [estimates for what healthy groups of the population should consume] for carbohydrate is set at 50% of your total energy intake. For example, if your daily energy intake is 2,500kcal then your carbohydrate contribution would be 1,250kcal or around 312g/day.

What is the difference between simple and complex carbs?

Essentially the difference is in the length of the carbohydrate chain. Simple carbs, or simple sugars, are short molecules which are readily broken down into glucose units and used for energy. Complex carbs are long chains of carbohydrates bound together, which are much harder to digest and in some cases, such as fibre, cannot be fully digested [fibre is still vitally important, however].

What switches would you recommend to eat healthier carbs?

Eating more complex carbs is not only beneficial from an energy provision perspective, often foods high in complex carbs bring with them various other nutrients – vitamins and minerals – and fibre, whereas foods high in simple sugars often contain few other nutrients. Quite simply eating more fruit, vegetables and wholegrains is a great place to start.

Staple foods such as pasta, rice and bread can easily be swapped for wholegrain alternatives. Refined cereals can be swapped for oats or muesli. Sweets and confectionary can be swapped for fresh and dried fruits.

Does eating protein make you feel fuller than eating carbs?

For most people, yes. For an equal amount of calories from protein and carbs, most people will feel fuller from the protein. This can be beneficial for weight loss or if someone is wishing to control their carbohydrate intake; including protein in a meal will help them feel fuller and hence reduce the desire to continue eating or eat again shortly after the meal.

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Nick Harris-Fry
Senior writer

Nick Harris-Fry is a journalist who has been covering health and fitness since 2015. Nick is an avid runner, covering 70-110km a week, which gives him ample opportunity to test a wide range of running shoes and running gear. He is also the chief tester for fitness trackers and running watches, treadmills and exercise bikes, and workout headphones.