Is Carb Cycling Good for Weight Loss?

  • Medical Reviewer: Mahammad Juber S
Medically Reviewed on 7/27/2022

What are carbs?

Carb cycling is an attempt to fine-tune your carbohydrate consumption to alter many aspects of your metabolism. There isn't much high-quality evidence for the weight loss benefits of carb cycling.
Carb cycling is an attempt to fine-tune your carbohydrate consumption to alter many aspects of your metabolism. There isn't much high-quality evidence for the weight loss benefits of carb cycling.

Your weight loss plan should keep you healthy and strong as you lose the extra weight. Many plans include a diet low in carbohydrates. Carb cycling is a method of optimizing your carbohydrate intake to meet your needs while dieting, fasting, and working out. When you're carb cycling, you consume carbs to meet your needs on some days and avoid them on other days. The aim of carb cycling is to consume carbohydrates when your body needs them and exclude them at other times. Such strategies in your diet plan can help your weight loss efforts. 

Carbohydrates, or carbs, are a significant part of the average human diet. Along with proteins and fats, they make up the bulk of your daily meals. Most carbohydrates are broken down by your body into glucose to provide energy for your cells and tissues. Carbohydrates in your diet are of three types — sugars, starches, and fiber.  

Sugars are simple carbs. Glucose, sugar (sucrose), lactose found in milk, and fructose found in fruits, are naturally occurring sugars. Your body metabolizes these molecules rapidly to yield energy. 

Starches are complex carbs. They're large molecules that consist of hundreds of molecules of simple sugars joined together. Your body needs to break them down to release energy. Starches are found in bread, potatoes, peas, corn, cereals, and pasta.

Fiber is also a complex carbohydrate. Human bodies can't break down these large molecules, so they provide no energy. They're usually excreted as they are in the feces. They add bulk to your meal, so you feel full. Fiber in the diet helps avoid constipation and lowers blood sugar and cholesterol levels.

Carbohydrates are an essential part of your diet. A typical diet provides 45% to 65% of its calories from carbohydrates. If you have 2,000 calories a day, you should have about 275 grams of carbohydrates. Always try to choose healthy foods for your carb intake:

  • Whole grains like whole-wheat bread, whole cornmeal, and oatmeal. They provide minerals, vitamins, and fiber.
  • Dairy products like milk and yogurt, which provide calcium and vitamins.
  • Legumes like lentils, dried beans, and peas, which provide dietary fiber and protein.
  • Fruits such as apples, bananas, berries, mangoes, and melons. Fruits are a rich source of vitamins and minerals. 

What is carb cycling?

Carb cycling is an attempt to fine-tune your carbohydrate consumption to alter many aspects of your metabolism. Your plan will include the same protein intake each day but vary carbohydrates according to your activity. Your carb cycling plan may have three low or zero carb days, two moderate carb days, and two high carb days. Meeting your calorie requirements will require including more fats on low-carb days. Carb cycling needs much more planning than a usual calorie-controlled diet.

One way is to match your carb cycling to your physical activity. If you go to the gym thrice a week, you could have carbs on those days. The carbs provide energy for your workout, prevent fatigue, and avoid the muscle loss sometimes seen with dieting

The days when you eat little to no carbs force your body to generate energy from other sources, like proteins and fats. But the days when you eat more carbohydrates might reverse this change. You must only eat a high-carb diet on the days you have a heavy workout, which uses up the calories. 

Daily carbohydrate requirement

Your body needs carbohydrates for energy. One gram of carbohydrate provides four calories when metabolized. This is about the same as a gram of protein and half as much as a gram of fat. A typical diet for adults takes in about 45% to 55% of its calories from carbohydrates, 10% to 20% from proteins, and the rest from fats.

Pre-exercise carbohydrate intake improves performance. But blood glucose levels can be maintained by breaking down glycogen stored in the liver if carbohydrates are not eaten. Exercising without eating leads to the usage of stored fat for energy. This might actually be better for weight loss.

Carb cycling and weight loss

There isn't much high-quality evidence for the weight loss benefits of carb cycling. In general, eating fewer carbohydrates and more protein is beneficial for weight loss. A higher amount of protein in the diet keeps you feeling full longer. Proteins are the most satisfying of the three macronutrients. Meals that keep you full for more extended help you lose weight. Carb cycling may contribute to weight loss by reducing carbohydrates and increasing protein in the diet.

Weight loss depends on reducing your calorie intake to less than your body's requirement. Carb cycling will work as long as the total calories consumed per day remain around 30% less than the requirement. Various diets with alternating low and high carbohydrates yield the same weight-loss as calorie-restricted low-fat diets and high protein diets.

Weight loss programs that alternate between calorie restriction (1,200 to 1,500 calories a day, for women) and high-calorie periods (2,200 calories a day) are also effective at weight loss. Diets with high protein and low carbohydrates, and diets with low protein and high carbohydrates, were also effective at weight loss. Overall, reduced calories and some physical activity work for reducing weight, regardless of the composition of the meals.

Carb cycling is believed to act by altering insulin sensitivity and release, as well as increasing the body's ability to burn fat as fuel. Two or three low-carb days in succession force your body to burn up stored glycogen and body fat.


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Carb cycling safety

One problem with eliminating carbs is that you're less likely to get enough fiber. A diet without fiber can cause problems in your digestive system. Constipation is a frequent problem with extremely low-carb diets. Consuming higher amounts of fats and proteins may also put you at risk for kidney and heart disease and increase your cancer risk. 

The body needs some carbs to function. Reducing carbohydrates in your diet to a very low level can cause fatigue, cravings, constipation, bloating, sleep disturbances, irritability, and indigestion.

These problems are likely if you take your carb cycling to extreme lengths. As long as your diet plan includes enough of all the macronutrients and micronutrients, carb cycling should not be harmful. Competitive athletes and bodybuilders mainly use carb cycling to increase muscle mass and reduce fat. It's a rigorous diet and used for short periods only.

Effective carb cycling

Carb cycling shouldn't cause a calorie shortage. On the days you cut out carbs, compensate by increasing protein and fats. Inadequate calories can cause muscle loss and poor energy levels. Weight loss diets should provide 1,900 calories a day for men and 1,400 calories a day for women.

Zero-carb levels may be unsustainable. Reducing carbs to 10% or so of your daily diet is more likely to keep you from raiding the refrigerator.

Low-carb days should never coincide with an intense exercise session. Carbs provide the energy for your workout. High-carb days should have some intense activity to avoid weight gain.

Balance in your diet is vital. Even when on a carb cycling plan, you must consume enough fruits, vegetables, starchy foods (wholegrain bread and pasta, potatoes), milk and dairy foods, meat, eggs, and fish.

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Medically Reviewed on 7/27/2022

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