Dirty Bulks vs. Whole Foods on Muscle and Fat Gain Summary
- Dirty bulks involve consuming a lot of processed foods like cereal, cookies, and muffins to achieve rapid weight gain. The study investigates lean and fat mass gains during bulking from high carbohydrate (i.e., highly processed foods) versus high fat intake (i.e., peanut-based foods) on muscle and fat gains in resistance-trained individuals.
- Both groups aimed for a 500 kcal daily surplus and followed a supervised hypertrophy-oriented training program three times a week for 10 weeks.
- Both groups gained lean, fat, and total body mass. The high-carb group gained more fat mass compared to the high-fat group. There was no statistical difference in lean mass gained between the groups.
- Incorporating more processed, carbohydrate-based snacks might help increase caloric intake for those struggling with weight gain. Conversely, individuals who want to prevent excess body fat may benefit from focusing on whole foods to control their surplus more effectively.
What is a Dirty Bulk
When trying to gain weight, there are two primary philosophies: lean bulks and dirty bulks. Lean bulking involves consuming whole foods such as chicken and rice to minimize fat gain while increasing muscle mass. On the other hand, dirty bulks include consuming a lot of processed foods like cereal, cookies, and muffins to achieve rapid weight gain. Eating a surplus is important for gaining muscle, as short-term calorie deficits impair lean mass gains but not strength, highlighting the importance of maintaining a caloric surplus for optimal muscle growth. (Murphy & Koehler, 2022) Studies also show that the type of calories consumed, whether processed or whole foods, can significantly impact body composition and health outcomes (Hall et al., 2019, (Monteiro et al., 2019). A new study, “A Randomized Trial of Healthy Weight Gain in Athletic Individuals,” compares these two bulking diets and sheds some interesting light on what diet you should use to gain weight. (Sanchez et al., 2024)
Review of the Literature on Dirty Bulks and Processed Foods
Individuals often focus on their diet to gain muscle without excess fat, particularly their calorie intake. Higher-calorie diets promote muscle gain but can also lead to fat gain. (Helms et al., 2023) Furthermore, athletes consuming a high caloric surplus experienced greater increases in muscle mass and a substantial increase in fat mass compared to those consuming a moderate surplus. (Garthe et al., 2013) When paired with resistance training, a modest caloric surplus strikes a balance between muscle gain and fat accumulation. Athletic individuals who consumed a moderate caloric surplus and resistance training experienced healthy weight gain, primarily in lean muscle mass, with minimal fat increase. This suggests a controlled caloric surplus can optimize muscle hypertrophy while limiting fat gain. (Iraki et al., 2019)
Processed Foods for Dirty Bulks
The relationship between processed food consumption and weight gain has been extensively studied. Previous research indicates that diets high in processed foods are associated with increased calorie intake and weight gain. For example, ultra-processed foods contribute to excessive calorie consumption due to their high palatability and low satiety. Similarly, a 2019 study demonstrated that participants consuming ultra-processed foods ate more calories and gained more weight than those consuming minimally processed diets. (Hall et al., 2019)
Overview of the Study Protocol
The study by Sanchez et al. (2024) aimed to evaluate the impact of consuming highly processed foods versus whole foods on weight gain in athletes. The diet was not a dirty bulk per se, but rather a highly processed carbohydrate diet compared to a whole food diet. The researchers randomized 32 resistance-trained men and women (19 men and 13 women aged 18-40 years) into two groups. Both groups followed a hypertrophy-oriented training program three days per week for ten weeks and received the same standardized, evidence-based healthy weight gain advice.
The groups differed in the type of snacks provided to achieve a 500 kcal daily surplus:
High Fat Group, Whole Food Group: Consumed snacks high in fat (peanut-based snacks such as peanut butter, trail mix with peanuts, peanut butter smoothies, and peanut butter cookies). The macronutrient distribution for the high-fat group was ~14% protein, ~31% carbohydrate, and ~55% fat.
High Carb Group, Processed Foods Group: Consumed snacks high in carbohydrates (processed snacks like muffins, fruit smoothies, rice pudding, and cereal). The macronutrient distribution for the high-carb group was ~3.5% protein, ~63% carbohydrate, and ~34% fat.
Dirty Bulks with Processed Foods Result in Faster Weight Gain
At the end of 10 weeks, both groups increased lean, fat, and total body mass. The high-carb, processed food group (i.e., dirty bulk) gained more total and fat mass than the high-fat group. There was no difference in protein intake between the groups. The high-carb group had a slightly higher increase in lean mass (1.9 kg vs. 1.3 kg) and body fat percentage (0.3% vs. -0.1%), but this was not statistically significant.
Interestingly, although there were supposed to be differences in fat and carbohydrates, the results were less than anticipated. At several points in the study, the highly processed food groups ate more fat and carbohydrates than the peanut group. The highly processed food group (i.e., dirty bulk group) consumed significantly more fat at three weeks (149 ± 50 vs. 105 ± 19 g). At the seven-week (124 ± 30 vs. 111 ± 27 g) and ten-week (127 ± 32 vs. 120 ± 39 g) time points. This larger caloric surplus in the carbohydrate-based snack group, driven by higher fat and carbohydrate intake, is corroborated by the greater increase in total and fat mass.
Dirty Bulks Result in More Calories Consumed
The findings suggest that the type of bulking diet can influence the amount of muscle and fat gained. The high-carb, high-processed food group (i.e., dirty bulk) achieved a larger caloric surplus, resulting in slightly greater gains in both muscle and fat. The muscle gains were not statistically significant, so if you are a football player looking to gain weight, processed food/dirty bulk will help increase weight gain faster. This aligns with previous research indicating that processed foods can lead to higher energy intake and weight gain. However, the study also highlights the importance of dietary composition. While both groups gained muscle, the high-carb group’s higher fat gain emphasizes balancing macronutrient intake to minimize fat accumulation during bulking.
Practical Applications: Lean vs Dirty Bulks
A dirty bulk diet of highly processed foods can lead to rapid weight gain and increased fat mass. If opting for dirty bulking, monitor overall caloric intake and maintain a rigorous training regimen to maximize muscle gain and control fat accumulation. Based on research, you don’t need to go overboard with a high-calorie diet; a small surplus will result in just as much gain in muscle and less body fat.
To optimize bulking results:
Track Caloric Intake: Ensure you have a controlled caloric surplus to promote muscle growth without excessive fat gain.
Balance Macronutrients: Aim for a diet high in protein with moderate carbohydrates and fats.
Choose Nutrient-Dense Foods: Prioritize whole foods, even in a dirty bulk, to ensure adequate nutrient intake and support overall health.
References
Garthe, I., Raastad, T., Refsnes, P. E., & Sundgot-Borgen, J. (2013). Effect of nutritional intervention on body composition and performance in elite athletes. European Journal of Sport Science, 13(3), 295-303. https://doi.org/https://doi.org/10.1080/17461391.2011.643923
Hall, K. D., Ayuketah, A., Brychta, R., Cai, H., Cassimatis, T., Chen, K. Y., Chung, S. T., Costa, E., Courville, A., Darcey, V., Fletcher, L. A., Forde, C. G., Gharib, A. M., Guo, J., Howard, R., Joseph, P. V., McGehee, S., Ouwerkerk, R., Raisinger, K., . . . Zhou, M. (2019). Ultra-Processed Diets Cause Excess Calorie Intake and Weight Gain: An Inpatient Randomized Controlled Trial of Ad Libitum Food Intake. Cell Metab, 30(1), 67-77.e63. https://doi.org/10.1016/j.cmet.2019.05.008
Helms, E. R., Spence, A.-J., Sousa, C., Kreiger, J., Taylor, S., Oranchuk, D. J., Dieter, B. P., & Watkins, C. M. (2023). Effect of Small and Large Energy Surpluses on Strength, Muscle, and Skinfold Thickness in Resistance-Trained Individuals: A Parallel Groups Design. Sports Medicine – Open, 9(1), 102. https://doi.org/10.1186/s40798-023-00651-y
Iraki, J., Fitschen, P., Espinar, S., & Helms, E. (2019). Nutrition Recommendations for Bodybuilders in the Off-Season: A Narrative Review. Sports (Basel), 7(7). https://doi.org/10.3390/sports7070154
Monteiro, C. A., Cannon, G., Levy, R. B., Moubarac, J. C., Louzada, M. L., Rauber, F., Khandpur, N., Cediel, G., Neri, D., Martinez-Steele, E., Baraldi, L. G., & Jaime, P. C. (2019). Ultra-processed foods: what they are and how to identify them. Public Health Nutr, 22(5), 936-941. https://doi.org/10.1017/s1368980018003762
Murphy, C., & Koehler, K. (2022). Energy deficiency impairs resistance training gains in lean mass but not strength: A meta-analysis and meta-regression. Scand J Med Sci Sports, 32(1), 125-137. https://doi.org/10.1111/sms.14075
Sanchez, A. D., Reynolds, J. C., Marinik, E. L., Kolb, R. D., Lozano, A. J., Davy, B. M., Hunter, G. R., & Larson-Meyer, D. E. (2024). A Randomized Trial of Healthy Weight Gain in Athletic Individuals. Med Sci Sports Exerc. https://doi.org/10.1249/mss.0000000000003427
