A Look Into the Research Behind Carb Back-loading

There’s been a fair amount of attention drawn to the term “carb back-loading” recently; I get a lot of questions about it, the marketing behind it seems almost too good to be true, and it’s pitched as the answer to getting lean and jacked. 

But what’s the science? 

Is it legit?

Carb Back-loading: What does the Research Say

A study conducted by The Robert H. Smith Faculty of Agriculture, Food and Environment, Institute of Biochemistry and Food Science, The Hebrew University of Jerusalem, Rehovot, Israel, found greater weight loss and hormonal changes after a 6-month diet with carbohydrates eaten mostly at dinner.

This study was designed to investigate the effect of a low-calorie diet with carbohydrates eaten mostly at dinner on anthropometric, hunger/satiety, biochemical, and inflammatory parameters. Hormonal secretions were also evaluated.

Seventy-eight police officers (BMI >30) were randomly assigned to experimental (carbohydrates eaten mostly at dinner) or control weight loss diets for 6 months. On day 0, 7, 90, and 180 blood samples and hunger scores were collected every 4 h from 0800 to 2000 hours. Anthropometric measurements were collected throughout the study.

Greater weight loss, abdominal circumference, and body fat mass reductions were observed in the experimental diet in comparison to controls. Hunger scores were lower and greater improvements in fasting glucose, average daily insulin concentrations, and homeostasis model assessment for insulin resistance (HOMA(IR)), T-cholesterol, low-density lipoprotein (LDL) cholesterol, high-density lipoprotein (HDL) cholesterol, C-reactive protein (CRP), tumor necrosis factor-α (TNF-α), and interleukin-6 (IL-6) levels were observed in comparison to controls.

The experimental diet modified daily leptin and adiponectin concentrations compared to those observed at baseline and to a control diet. A simple dietary manipulation of carbohydrate distribution appears to have additional benefits when compared to a conventional weight loss diet in individuals suffering from obesity. It might also be beneficial for individuals suffering from insulin resistance and the metabolic syndrome.

Further research is required to confirm and clarify the mechanisms by which this relatively simple diet approach enhances satiety, leads to better anthropometric outcomes, and achieves improved metabolic response, compared to a more conventional dietary approach.  

What is Carb Back Loading?

In the simplest terms, “Carb Back-loading” is eating protein and fat in the morning and early afternoon, and then “loading” your carbohydrates at night. Some of you may know the importance of replenishing glycogen in the post-workout period. But how does carb back-loading work for the average population, and can it work for hard-charging athletes?  Here are some points for thoughts:

• Protein and fat increase the thermic effect of food, satiety, and lipolysis through cortisol release.

• Carbohydrates, timed at night after this effect, attenuate cortisol, increase serotonin, and preserve hormonal health.

• Over-consumption is less, due to 1) depleted glycogen from the day, and 2) higher pro earlier reducing hunger

• Inflammation markers like CRP, IL6, and TNFa were likely lower due to lower overall glucose intake.

Carb Back-Loading for Athletes:

• Can this work? Maybe. Training glycogen depleted has shown to improve the use of fatty acids as fuel. But, purposeful abstinence of carbs post-workout can increase cortisol output, and lead to quicker over-reaching/over-training. You can read about the difference in nutrition for athletes as well as general population clients here. It’s a fine line to walk. Learn how to create nutrition plans for your client’s needs here.

There are Some Caveats:

• Food quality is still of the absolute utmost importance. “Carb-Backloading” is not an ok to crush pizza and doughnuts, as promoted by certain individuals. Here at OPEX Fitness we, understand the importance of nutrition beyond protein, fats, and carbs, especially in relation to performance.

In the end, carbohydrate partitioning (a term more accurate, and one coined a long time prior to any “back-loading”) can be a valuable tool for the sedentary, the novice athlete, and the experienced athlete – it just needs to be applied in the right manner. Learn how to create nutrition programs based on your client’s specific need with The Free 7-Day OPEX Coaching Course.

Author: Mike Kesthely, Dynamic Nutrition, OPEX Coach

Source: Sofer, S. , Eliraz, A. , Kaplan, S. , Voet, H. , Fink, G. , Kima, T. and Madar, Z. (2011), Greater Weight Loss and Hormonal Changes After 6 Months Diet With Carbohydrates Eaten Mostly at Dinner. Obesity, 19: 2006-2014. doi:10.1038/oby.2011.48