All of these diets have one thing in common: They force you to drastically slash the number of carbs you eat in order to achieve weight loss success.
These diets can be successful for a short period of time. But they’re often difficult, if not impossible, to maintain for many people.
Now a new diet approach called carb backloading suggests it’s not the number of carbs you eat but when you eat them that really matters.
Carb backloading is a carb-restrictive approach that encourages you to eat all of your carbs later in the day. This way, proponents say, you can capitalize on your body’s natural insulin sensitivity cycle, store less fat, and build stronger muscles.
But is it a good idea for you to try? There are a few factors to consider.
What is carb backloading?
The idea behind carb backloading is simple: Eat very few carbs at breakfast and lunch. Eat more carbs at dinner after a workout.
This diet theoretically capitalizes on your insulin production and insulin sensitivity cycles, says Alfred Schofield, co-founder of VitalFit Nutrition.
“At different times of the day, our bodies process carbohydrates differently. When our bodies are at rest or in a calm state, the insulin brings more of the carbohydrates to the fat cells, whereas when we are in a state of high activity or stimulation, more of the carbohydrates are delivered to our muscles,” Schofield said. “Over time, the storage of excess carbohydrates in fat cells is what can lead to weight gain.”
Reversing your body’s carb-storing tendencies can also help you burn more fat by stripping your body of its preferred energy source — carbs — and forcing it to turn to stored fat for fuel.
Each night while you sleep, your body begins burning stored fat. If you don’t load up on carbs at your first meal, this fat burning continues. This fat-burning state is a primary cornerstone of the popular keto diet.
With carb backloading, however, you eat too many carbs to maintain ketosis, or the fat-burning state.
“Users avoid carbohydrates through the day and wait to consume carbohydrates after a workout or much later in the day,” Schofield said. “This way, our bodies burn the stored carbohydrates in fat cells throughout the day. Then, when consuming carbs later in the day, these carbohydrates are brought as fuel to the muscles after a workout, thus minimizing the storage of carbs in fat cells.”
To properly practice carb backloading, you should aim to limit your carb intake during the day to less than 30 grams, said Andrew Woodward, MS, RD, CSO, the oncology nutritionist for Loma Linda University Medical Center in California. “That’s about two small slices of bread or one piece of fruit, for example,” he said.
Follow that with a healthy dinner with carbohydrates. You may also want a carb-rich snack before bed.
What does the research say?
There isn’t much research yet on the long-term effectiveness of carb backloading.
Small studies suggest eating carbs with protein at night may help curb appetite and promote weight loss. However, these studies are very small, and Woodward said they don’t significantly support the carb backloading concept.
“This is a theory based on two relatively weak studies,” Woodward said. “And it’s not consistent with a vegetarian diet or a healthy Mediterranean style of eating. Consequently, I don’t see that it would be helpful for most people.”
Likewise, Woodward said, carb backloading might be dangerous for some people, including people with diabetes or hypoglycemia, people who are pregnant, people with a history of eating disorders, underweight people, and other higher-risk individuals.
“It would be confusing and overly restrictive to people that want to establish or maintain healthy eating habits,” he said.
Robert Herbst, a personal trainer, weight loss and wellness coach, and a powerlifter, said that while he knows the research to support carb backloading is nonexistent, the diet has been helpful for him.
“When I was climbing mountains in Nepal in the late 1980s, every night I would have a big bowl of noodles for dinner. As a practical matter, noodles were convenient because the Sherpas had a lot of noodles and they were very light to carry,” he said. “I appreciated them because I viewed eating noodles like the carbo loading that marathoners did, and they would give me energy for the next day’s climb.”
When he returned stateside, Herbst resumed powerlifting and kept his carb backloading practice. “This helped my muscles replace the glucose that I’d been using during the workout,” he said. “On rest days, I would still have carbs with dinner to load my muscles for the next day. Unlike what strict backloaders do, I would also have some carbs in the morning as I needed energy for my day job as an attorney.”
Herbst said it wasn’t called carb backloading then — it’s just what he did to help fuel his workouts, build muscle, and keep fat at bay — but his approach is based on these same basic principles promoted today.
“Proponents of backloading have attempted to describe it in terms of nutrient timing and insulin sensitivity and have come up with strict programs to justify what they are doing,” Herbst said. “I think they are overthinking things. They also run the risk of making a program that is too uncomfortable to follow, with people not getting enough carbs during the day.”
Who might benefit from carb backloading?
Because the research is so limited, there’s no clear evidence about the long-term effects of carb backloading on weight loss and overall health.
“Overall, users of this diet believe that it will help shed fat and help promote muscle growth,” Schofield said. This is, in part, what makes carb backloading so popular among body builders and people focused on burning fat and adding muscle while keeping weight gain low.
“Other proposed benefits of this diet are that it will reduce cravings, as you can indulge at night, and aid in sleep due to the increased production of tryptophan,” Schofield said. Tryptophan is an amino acid that helps regulate sleep.
But don’t be in a hurry to down a pint of mint chocolate chip after a run or load up on a chocolate-covered nougat bar after a heavy legs session, Schofield said. The quality and quantity of the carbs you eat still matters.
“The best carbs for this diet are complex carbs that take the most time to break down, thus helping fuel your muscles for the longest period of time,” he said. “While this diet’s merits include flexibility and the ability to eat freely at night, complex carbohydrates from natural sources will remain the best options for maximum results.”
“In a world of paleo and keto diets, carb backloading should not be seen as an excuse to eat junk,” Herbst adds.