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What Is Dirty Bulking

What Is Dirty Bulking? Is It Effective or a Dieting Mistake…

The term ‘dirty bulking’ gets used a lot in bodybuilding/dieting and often people will have strong opinions about it. We all know that there are different dieting strategies used to build muscle mass or lose body fat but, what is dirty bulking?

Dirty bulking is a dieting strategy used by people looking to build muscle mass and gain weight. A bulking phase involves people consuming a calorie surplus and a dirty bulk is an extreme method that involves eating “junk” food and consuming excessive calories well above maintenance requirements. 

Here I’m going to explain exactly what dirty bulking is in a bit more detail as the above is a brief overview. This will include why people do it, if it’s effective, and if it’s bad for you. I’ll also outline what foods are considered ‘dirty’ and give you some examples so that you know everything there is to know about dirty bulking! 

What Is Dirty Bulking?

Many of you will already be aware of what bulking is. It essentially refers to the process whereby you consume a higher amount of calories than you use. This surplus of calories is then used to increase body mass. Bulking is popular amongst bodybuilders, athletes, and non-professionals looking to make gains.

I have a particular interest in bulking as I was historically a “hardgainer” and find it difficult to gain and hold size – though I’ve had my fair amount of successful bulks over the years. I’d recommend checking out this section on my site for more dedicated articles on bulking

When ‘clean’ bulking, this surplus of calories is usually restricted and controlled with a specific number of calories as your target. For example, you may have your calorie target as 500cal more than the amount you’re using day to day through energy expenditure. For a period of time, you would stick tightly to this calorie target.

This calorie target is usually increased over a period of 6 months so that you’ll see gradual gains in body mass. Bulking in this way is often something done long-term and can lead to impressive gains when done over time. 

When clean bulking, this excess of calories is also achieved by eating certain foods. Usually, it’s ‘healthy’ foods like those that are high in nutrients and protein like meat (or meat alternatives), fish, rice, pasta, nuts, avocado, eggs, potatoes, etc.. that will make up a lot of this, as the goal is to increase body mass in a controlled way. 

As a result, you’d want to be keeping track of macronutrients and other factors to ensure that you’re eating the right foods to promote gains in muscle mass.

Bulking goes beyond just a diet though. This period of calorie surplus is also usually combined with serious training, like weight training and resistance training, in order to increase muscle mass and overall strength.  

Dirty bulking differs from regular ‘clean’ bulking in that it involves an unmeasured amount of calorie intake, and there are no restrictions on what foods you can eat. The overall goal is essentially to gain as much mass as possible by consuming as much as possible.

So dirty bulking is obviously very similar to clean bulking. The difference is that you consume more calories, as many as possible really, often from different foods as there aren’t any restrictions on what you eat. You would therefore expect to see more noticeable gains in terms of increasing overall body mass when dirty bulking.

Like clean bulking, dirty bulking is not just about diet. This period of higher calorie consumption is usually combined with intensive training, like weight training and other forms of workouts like resistance training, in order to maximize muscle mass gains.

Check out this video on dirty bulking, as well as the impact of dirty bulking:

Why Do People Dirty Bulk?

Dirty bulking is popular because there are no restrictions on what amount of food or the type of food you eat, which makes it a popular alternative to restrictive or controlled diets. It’s also popular as you can rapidly increase body mass through this approach. 

There are three common reasons why people choose to dirty bulk:

1. Increased Calorie Consumption

To expand on this a little bit more, with dirty bulking there really aren’t any limits on the amount of food that you consume. Overall, you want to be eating as much as you can tolerate in order to gain as much body mass as you possibly can.

This means exceeding your total calorie expenditure (the number of calories you use throughout the day including during workouts) by a lot over a period of weeks to months. When consuming foods that are more calorie-dense (but also less nutrient-dense) you are able to eat more without becoming as full. 

This is one of the key “benefits” as bulking can be very hard when trying to stick to nutrient-dense foods which are more filling and satiating. 

A plate of broccoli which is high in fiber and dietary carbs is a lot more filling, satiating, and takes considerably longer to digest than a donut. The donut will also have a much higher calorie content so when dirty bulking, it’s typically easier to consume more calories. 

Types of Food

There are also no limits on what foods you eat when dirty bulking. This means that popular foods that would typically be restricted or eliminated on other diets, particularly those that are nutritionally dense like pizzas and chocolate, are encouraged when dirty bulking.

With no limits on the type or amount of food you eat, it’s understandable that many people find dirty bulking to be a popular way to gain body mass in comparison to very restricted or controlled diets.

These aren’t necessarily optimal though and there are definitely some better bulking foods that you can consume – even when dirty bulking. 

Ignoring the above, you can also check out some of the best dirty bulking foods for total calorie quantities (rather than calorie quality).


Dirty bulking is also popular because it can deliver results. Consistently consuming a high level of calories that exceeds your total expenditure is going to lead to body mass gains, and combining this with intense workouts is going to help gain muscle mass. 

When clean bulking you might do this more steadily and have a more gradual and controlled increase in calorie intake. With dirty bulking the gains you make can be bigger and faster because of the number of calories you’re consuming. 

With the rapid increase in body mass though with dirty bulking, there’s, unfortunately, a huge downside in that the rate of muscle you can grow naturally within a timeframe is limited which leads to some key issues with dirty bulking…

Is Dirty Bulking Bad?

There are numerous downsides to dirty bulking. This includes unwanted fat gain from eating a calorie surplus and changes to blood sugar levels from eating high calorie and high sugar foods, which can also badly affect your mood.

Fat Gain

To expand on these downsides some more as they are really important to consider, the goal with dirty bulking is to increase body mass, particularly muscle mass. There can be different reasons for this, including increasing strength so you’re able to bench more or to improve your physique and look more muscular.

However, because calorie consumption when dirty bulking isn’t measured and is consistently above calorie expenditure it’s very easy to end up adding fat, as well as muscle. In fact, research suggests that most of the body mass gained when dirty bulking comes from fat, not muscle gain.

This is one of the key issues why people gain too much body fat when bulking without understanding why.

This is because not all foods promote or support muscle growth. Eating fatty foods, as well as those with high carbohydrate and sugar contents, are linked with fat gain. As you’re not tracking what food you’re eating when dirty bulking it’s very easy to gain body fat instead of muscle.

So, dirty bulking runs the risk of changing your body composition by adding body fat, which isn’t ideal especially if your goal is to improve your physique and look more muscular. 

Check out this video on dirty bulking and fat gain: 

Blood Sugar Levels

Another drawback is the impact dirty bulking has on blood sugar levels. Like I’ve mentioned, when dirty bulking there aren’t any restrictions on what food you eat. As a result, a lot of people end up eating high-calorie, nutritionally dense foods that are often highly processed, high in sugar, and devoid of fiber.

Eating these kinds of foods can spike your blood sugar levels. Following this spike, blood sugar levels fall – often called a sugar crash – and your body craves sugary foods to spike these levels again. As a result, you’ll consistently experience cravings and be stuck on a cycle of blood sugar spikes and crashes.

Whilst eating more high-calorie and often high sugar food is part of the plan during dirty bulking, it can have long-term consequences. It’s difficult to suddenly stop eating all of this kind of food when you stop dirty bulking, as your body will still crave it and you’ll still be experiencing these blood sugar crashes. 

As a result, it can be harder to sustain a healthy diet long-term after dirty bulking and you might find that you experience more setbacks afterward.

Negative Health Impact

Also, consistently eating these kinds of foods increases your risk of developing diabetes, as well as having heart disease or a stroke. Similarly, eating high-fat foods increases your risk of heart disease and plenty of other negative health impacts. So dirty bulking has serious potential downsides when it comes to your physical health and well-being. 

Dirty bulking can also have a bad impact on your mood and energy levels. We’ve all heard about the importance of eating a healthy and balanced diet for our physical health, but it can also affect our overall mood.

As I mentioned, diets that are heavy in processed foods, high-calorie foods, and high sugar foods can have a bad effect on blood sugar levels. Blood sugar fluctuations can lead to lethargy, essentially making us feel very tired, which isn’t ideal considering that a key part of dirty bulking is intense training. 

The bottom line then is that there are serious drawbacks when dirty bulking, including its impact on body composition, with unwanted fat gain a serious possibility. Dirty bulking also comes with health risks, with negative health effects another serious drawback of eating these kinds of foods, especially long-term. 

Dirty Bulking Foods

When dirty bulking there aren’t any restrictions on what foods you can eat or the quantity of foods you consume. But typically you’d want to eat foods that are going to help you gain as much as possible. 

Foods that are considered ‘dirty’ are those with high-calorie contents. Ideally, you’d also want a mix of protein, carbs, and fat. Here I’ve listed 10 of the most popular foods that are considered dirty that you would look to be consuming a lot of when dirty bulking:

  1. Pizza
  2. Pasta
  3. Burgers
  4. Fast food
  5. Candy bars
  6. Ice cream
  7. Meat and meat alternatives that are high protein
  8. Cheese
  9. Nuts and nut products
  10. Milk (especially full fat versions)

Final Thoughts

I’m a big advocate of a sensible and sustained bulking period. I’ve discussed before that a typical bulking phase should last anywhere from 8 – 18 months as it’s a slow process to build muscle, any rushed attempts will usually result in more (and unwanted) excess body fat being stored as a result. 

With this in mind, dirty bulking will often cause more issues and inconvenience when used as a dieting strategy over a more sustained bulking approach like a clean or lean bulk. 

For information purposes only and to answer the topic of this article – A dirty bulk is a dieting strategy that involves consuming a large quantity of calories, mostly from calorie-dense foods like fast-food and high-sugar foods. The purpose of a dirty bulk is to have a large calorie surplus to promote maximum muscle growth in a short period of time. 

If you’ve found this informative, you might also want to check out a more direct (or debatable) article: 
Why dirty bulking is a waste of time

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