Want to gain muscle mass?
Plan on lifting heavy, eating plenty of protein, and consuming a caloric surplus.
But you’ve got two choices for shoveling in those extra calories: clean bulking or dirty bulking.
One is more difficult, yet healthier, while the other will pack on the pounds faster—with a much higher chance of gaining extra fat.
In this article, you’ll learn the basics of bulking diets, the differences between clean and dirty bulking, and which is a better fit for your goals.
What is Bulking?
Bulking or a bulking diet is the practice of intentionally adding weight by eating more calories than you burn.
Typically, people who want to become more muscular use a combination of weight training and a high-calorie, high-protein diet.
And sound science supports this time-tested practice: combined with weight training, extra calories and protein increase muscle protein synthesis (the technical name for repairing or building muscle)[*][*][*].
Therefore, for bulking, at Levels we recommend a caloric surplus of 250-500 calories (kcal) per day, plus 25-30% of your daily calories from protein.
Also, scientifically speaking, adding muscle has benefits beyond aesthetics and physical performance. Research suggests that additional lean muscle mass enhances your quality of life and may help prevent serious illnesses[*].
However, there’s more than one way to bulk up. Keep reading to learn the difference between clean bulking and dirty bulking!
Clean Bulk vs. Dirty Bulk: What’s the Difference?
Clean bulking refers to a style of bulking that focuses on healthy food choices while attempting to minimize fat gain.
Here are the hallmarks of clean bulking:
- Eating organic, local, and whole foods when possible
- Closely tracking macronutrients
- Adjusting calorie intake when necessary to avoid unwanted fat gain
However, keep in mind that there’s no official definition of clean bulking. Some people might consider a low-carb, grain-free diet “clean,” while others might choose to avoid fat.
But in general, clean bulking is about eating healthy and staying lean as you add muscle mass. When we say clean bulking here, that’s what we’re talking about.
In contrast, dirty bulking is everything that clean bulking isn’t:
- Convenient, calorie-dense food choices, usually including processed foods and fast foods
- Less focus on minimizing fat gain compared to clean bulking
- Typically high in protein, but with less concern over other macros
- A large caloric surplus to ensure weight gain
In fact, at its most extreme, you can think of dirty bulking as “weight gain at any cost.” Some people are so tired of being skinny that they’ll do just about anything to grow.
And as you might imagine, dirty bulking diets can also vary a lot depending on the individual.
Which style of bulking seems more appealing to you? Before you make your final decision, let’s learn about the pros and cons of each.
Pros and Cons of Clean Bulking vs. Dirty Bulking
Ease or Difficulty
When it comes to ease of use, dirty bulking is the undisputed winner over clean bulking.
In fact, the difficulty and complexity of clean bulking are essentially the reasons dirty bulking exists!
Whereas clean bulking diets emphasize healthy, nutrient-dense foods, dirty bulking diets prioritize easily-available calorie-dense foods.
And for people who require a very high daily calorie intake, lack a hearty appetite, or aren’t organized enough to grocery shop and food prep multiple times per week, dirty bulking is extremely appealing because it’s so much simpler.
Done correctly, clean and dirty bulking both work well for muscle growth.
All you need to build muscle is weight training, adequate protein, and a caloric surplus.
But as we already discussed, clean bulking isn’t as easy as dirty bulking. Some people start with a clean bulking diet, get impatient, and soon go “dirty.”
However, if you can’t grow on a clean bulking diet, you’re probably doing it wrong—you simply need more calories, more protein, or both. Knowing which healthy foods to eat to get bigger helps a lot.
Also, during a clean bulk, some people are so concerned about fat gain that they undereat, which reduces muscle protein synthesis and undermines results—however, that’s more of a mindset issue[*].
In the end, clean bulking and dirty bulking are equally effective for building muscle. Anyone who achieves a caloric surplus and eats enough protein can grow, regardless of whether they eat “clean” or “dirty.”
Clean bulking is all about avoiding fat gain, so there’s no question that it’s the superior choice if you want to stay lean.
Fat gain is one of the major downsides to dirty bulking. That said, the mindset you bring to dirty bulking is also important.
For example, if you insist on “weight gain at all costs,” you’re definitely going to gain some fat along with your newly built muscle.
On the other hand, a middle ground exists. You can use an aggressive "dirty bulking" style approach that includes convenient, calorie-dense foods and a high calorie surplus while also monitoring your body composition as a form of damage control.
But is there anything wrong with temporarily gaining fat? Is it such a problem?
A lot of people who dirty bulk embrace the fat gain, which isn’t necessarily wise.
Although some fat gain is inevitable as you gain a significant amount of muscle mass, excess fat gain slows your long-term results. Switching over to a fat loss diet takes time away from building muscle in the future and also results in losing hard-earned muscle.
For the majority of people, keeping fat gain relatively limited is the most efficient bulking strategy.
Bottom line: you can use a caloric surplus diet to force weight gain, but not muscle gain. A reckless, all-out dirty bulking diet will ensure you gain weight, but a significant portion of it will be fat.
Nutrition and Health
Honestly, do you think a dirty bulking diet is good for your health?
If you include lots of processed foods and fast foods in your bulking diet, you’re basically recreating the “Standard American diet,” which many researchers think has increased the prevalence of health problems in the United States[*][*].
Let’s take a closer look at what happens when you eat for convenience rather than health:
- Diets high in processed foods are low in micronutrients and high in added sugar[*][*][*]
- Inflammatory omega-6 oils in processed foods raise your risk of cardiovascular disease, cancer, and inflammatory and autoimmune diseases[*]
- Natural and artificial estrogen-mimicking compounds in processed foods disrupt reproductive and hormonal function, especially in men[*][*]
Also, as we’ve already discussed, eating processed foods increases the likelihood of obesity[*].
Sugary carbs, in particular, increase the accumulation of belly fat, which raises the risk of heart disease and cancer[*][*].
The takeaway: science clearly shows that eating a diet high in calorie-dense, processed foods results in micronutrient deficiencies and, over time, serious health problems.
And even if you learn to embrace the love handles you gain from all-out dirty bulking, your doctor won’t feel the same.
Therefore, if you value your health, stick with clean bulking—or at least limit the amount of time you spend dirty bulking, and be sure you unlearn any bad habits once you’re finished.
Performance and Recovery
For supporting performance and recovery, clean bulking and dirty bulking are tied.
As an example, plenty of powerlifters or non-weight-class athletes use a perpetual dirty bulking diet.
Ultimately, eating tons of calories and protein is an effective way to fuel performance, whether or not you eat “clean” or limit fat gain.
However, keep in mind that your physical performance will ultimately suffer if you experience diet-related health problems. That’s why long-term, a clean bulking diet is the better choice, even if you don’t care about aesthetics.
Dirty bulking is generally cheaper than clean bulking, and sometimes much less expensive depending on how you define “clean bulking” (personal chef, anyone?).
Conversely, health is priceless, and having future medical issues from years of eating dirty is a costly proposition.
Also, keep in mind that clean bulking doesn’t mean that you have to spend half your paycheck on food.
If you’re having trouble affording clean bulking, you need to focus on low-cost bulking staple foods that won’t break the bank.
The Bottom Line
Clean bulking and dirty bulking both work for gaining muscle mass.
But the fact that dirty bulking is easier and—as a result—more effective for some people is undeniable.
On the other hand, dirty bulking also brings a much higher risk of fat gain and (over time) health problems.
However, as long as you stop before you gain massive amounts of fat, there’s nothing wrong with the occasional dirty bulk.
But if you care about your health and appearance, don't dirty bulk forever.
Want to learn the best tips for bulking up with minimal fat gain? Check out Clean Bulking: 13 Diet and Training Tips to Gain Muscle, Not Fat.
Do you have any bulking experiences or questions you’d like to share? Let us know in the comments!