Carb cycling is a dietary strategy that involves intentionally varying your carbohydrate intake on different days, weeks, or months. Followers of this plan may choose to alternate between high-carb, moderate-carb, and low-carb periods, or just high and low-carb phases. The diet's objective is to try and optimise metabolic efficiency, energy availability, and potentially encourage weight and fat loss.
Why are carbs important?
Before we get into the nitty-gritty of the carb-cycling diet, it's useful to learn more about carbohydrates, and their role in the body.
Carbohydrates, or carbs, are the primary source of energy used in the body. There are two types of carbohydrates: simple carbs with up to two sugar molecules, and complex carbs which contain at least three molecules. Simple carbs are easily metabolised and so can provide a quick spike of energy. In contrast, complex carbs take longer to digest and typically are full of healthy fibre which slows down digestion. Although simple carbs can sometimes be utilised in training when instant energy is required, overall when carb cycling, it is preferable to consume more of these nutrient-dense complex carbohydrates, especially on high-carb days.
Complex carbs provide more sustained energy sources and keep blood sugar levels stable, which helps to curb sugar cravings and maintain a healthy metabolism. Kerry Beeson BSc (Nut. Med), Metabolic Balance Coach
Does carb cycling work? The science behind carb cycling
It takes a lot of planning and commitment, so a key question that most people ask before starting this diet is, does carb cycling work? Is all the effort going to be worth it? Before embarking on any diet, it's definitely sensible to do a little research to see what the science says.
The concept of a diet based on carb manipulation and intermittent energy restriction is built around our body's physiological responses to carbohydrate consumption and availability. It is believed to have been originally developed by six times 'Mr. World Fitness' winner, Franco Carlotto, back in the 1980s, who shared the principles of the diet in his book, The Carb Cycle.
Since then, there haven't been too many scientific studies which have looked specifically at the effects of a carb-cycling diet programme, and much of the supporting evidence has been derived from studies which look at either carbohydrate restriction or loading. Carb cycling aims to provide carbs when your body most requires them and restricts them when not required - this helps to match your body's needs more efficiently:
How to do carb cycling
Before you embark on a carb cycling diet, you need to make sure that this approach is right for you, your body, your health goals, and your lifestyle.
Carb cycling and macronutrient distribution
When following a carb cycling diet, you'll also need to vary your intake of other macronutrients, depending on whether you're having a high, moderate, or low carb day.
Individual needs will vary depending on personal goals, age, sex etc. Protein intake is crucial across both phases, and intake should remain constant at around 40% of daily calories. Aim for 1.6-2.2 grams of protein per kilogram of body weight daily to support muscle protein synthesis and recovery. Find out more about protein intake on our blog:How much protein do I need?Fat intake varies significantly between phases, with higher fat intake on low-carb days.
Carb cycling and exercise
For maximum benefit, your high and low-carb days should be arranged around your training schedule:
Carb cycling and body composition
Research suggests that carb cycling may help to promote positive changes in body composition by promoting fat loss while still preserving lean muscle mass.[4] However, individual results may vary, and it might be necessary to stick to the diet for an extended period, which might be difficult for many people in the long term. To achieve these results, it's also important to do the carb cycling plan in combination with a supporting exercise regime.
If you're trying to lose fat to achieve more defined muscles, you may be interested to read our article about bulking and cutting.
Can carb cycling help you lose weight?
Most followers of this diet want to know how to use carb cycling for fat loss or weight loss. Many people consider a carb cycling diet for weight loss, especially if they have previously been following another diet plan and their weight loss has plateaued, or they may be looking to lose fat after a period of bulking. By encouraging the body to utilise fat for fuel on low-carb days, carb cycling may encouragefat loss[4,5,6,7] which can contribute to overall weight loss, though this would still need to be in conjunction with a calorie deficit.
For more information about calculating an appropriate calorie deficit, read our article:How to lose, gain, or maintain with Prep Kitchen.
Take a look at our range of calorie-balanced,weight-loss meals.
Benefits of carb cycling
Both low and high-carb phases can have unique benefits[3]:
Challenges of carb cycling
Whilst there are numerous potential benefits to undertaking this dietary protocol, it also presents some challenges. It's good to be aware of these before starting the diet, so you can anticipate and address any difficulties or concerns beforehand:
Practical tips for successful carb cycling
Successful carb-cycling takes a lot of research and commitment. Before you start, it can be helpful to make sure that you have a good structure for success in place:
Conclusion
Hopefully, you now have a good overview of the basic principles of carb cycling. Here's a quick recap of the key points:
When combined with a balanced diet and tailored exercise, carb cycling can be an effective tool for helping to achieve your health and fitness objectives. Good luck!
If you enjoyed this article, take a look at these other related articles on the blog:
How to lose weight and keep it off
What is bulking and how does it work?
Are you eating too much sugar?
