Dirty bulking is an intense period of weight gain to support strength and muscle gains. There are no limitations on food, and high-calorie shakes and gain powders are often used.

While weight loss is a more common goal in today’s day and age, some people are interested in gaining weight for specific purposes.

In the world of bodybuilding, strength sports, and certain team sports, a common term for gaining weight is often tossed around — dirty bulking.

This article reviews dirty bulking, its possible negative side effects, whether it’s effective, and some foods to eat and avoid when following the method.

In general, the term bulking refers to a controlled phase of being in a calculated calorie surplus and combining it with sufficient resistance training to boost muscle and strength gains.

A calorie surplus involves consuming more calories than you burn, which can lead to weight gain in the form of muscle or fat.

Dirty bulking takes this a step further and can be defined as a period of unrelenting weight gain by any means necessary to promote muscle and strength gains. It’s usually paired with high-intensity resistance exercise to complement these adaptations.

The approach may be utilized by off-season bodybuilders, weightlifters, powerlifters, or the average gym-goer looking to pack on some size.

When following a dirty bulk, no foods are off-limits. The goal is to eat as much as tolerable to increase body mass.

Often, high calorie shakes and mass gain powders are utilized during a dirty bulk to promote a calorie surplus and subsequent muscle gains.

While this may work for some, others may find that the negative side effects outweigh the benefits.


Dirty bulking is a method of rapid weight gain that’s usually paired with high-intensity resistance training and used by various athletes to promote muscle and strength gains.

While a dirty bulk can surely cause weight gain, you may wonder whether it’s an effective long-term strategy for muscle gain.

Here are a few upsides to following a dirty bulk.

Ensures a calorie surplus

Just as many people find it difficult to lose weight, others find it hard to gain weight.

For these individuals, a dirty bulk may be a helpful tool, as it usually promotes a significant calorie surplus and thus leads to weight gain (1).

This weight gain is best translated to muscle gain when paired with a proper resistance training program, which is another major aspect of dirty bulking that cannot go overlooked.

With more conservative weight gain methods, results may be quite slow due to an insufficient calorie surplus. Thus, a dirty bulk may be beneficial in this context.

Can aid muscle and strength gains

Programmed weight gain is usually employed to promote muscle and strength gains in strength, physique, and some team sports.

For muscle gains to occur, a sufficient calorie surplus is required, usually 10–20% additional calories for most people (2).

The dirty bulk usually exceeds this range, thus likely contributing to sizable muscle and strength gains for most people when combined with a proper resistance training regimen.


A dirty bulk can be effective in certain situations in which weight gain is desired. It provides a calorie surplus that can lead to muscle and strength gains when combined with resistance training.

Along with the potential muscle and strength gains associated with dirty bulking, it comes with some possible negative side effects.

May promote unwanted fat gain

Given that calorie intake is not usually tracked on a dirty bulk, it’s easy to achieve a calorie surplus, which undoubtedly leads to weight gain. Though some of this weight will be from added muscle, a sizable percentage will be from added fat mass (3).

When it comes to strength and physique sports, the goal is usually to maximize strength and muscle gains, respectively.

Specifically in physique sports, such as bodybuilding, competitors are judged on their muscle shape and size. Excessive fat gain likely makes it more difficult to get into shape when it comes time for competition (2).

In terms of strength and power sports, such as Olympic weightlifting and powerlifting, there are usually weight classes within which competitors must compete. Excessive fat gain may make it more challenging to achieve a given weight class.

For athletes participating in team sports, a dirty bulk could leave them out of shape when it comes time for pre- and in-season training.

Lastly, for the recreational gym-goer looking to put on some muscle, gaining too much fat may inhibit their goal of improving their physique.

Can affect blood values

Along with the potential for excessive fat gain, there are other possible negative health effects to consider. When following a dirty bulk, the intake of processed carbs and saturated fats is usually rather high.

Consuming too many of these foods has been associated with elevated cholesterol and blood sugar levels, leading to an increased risk of health conditions like high blood pressure, stroke, cancer, and diabetes (4, 5, 6, 7).

It’s important to note that most studies on the topic have been conducted in non-exercising individuals.

Though starting a dirty bulk may increase your short-term risk of certain health conditions, resuming a nutritious, unprocessed diet will likely undo these effects.

The best way to monitor these important health markers is to have a blood test at least once per year, along with a physical. More frequent testing may be beneficial if you have a history of a certain health condition (8).

You may feel sluggish

When following a dirty bulk, high calorie foods are eaten to promote weight gain.

Many of these foods are processed and contain large amounts of refined sugars and sodium, which can lead to water retention and fluctuations in blood sugar levels (9, 10).

This may leave you feeling sluggish after several days of following the diet.

One study suggests that a diet high in simple carbs can lead to increased fatigue and symptoms of depression (11).

These symptoms must be taken into consideration before starting a dirty bulk.

Should not be followed long term

Though dirty bulking can be effective in certain situations, it’s usually better off followed as a short-term approach during the off-season of various sports.

Following a dirty bulk for an extended period can lead to compromised health.


Following a dirty bulk may cause several negative side effects, including excess fat gain, sluggishness, and abnormal levels of some important health markers. Thus, it’s best followed as a short-term strategy.

When following a dirty bulk, there are not many foods that are off-limits due to the diet’s unrestrictive nature. Here are some foods to eat and avoid:

Foods to eat

  • high protein foods, such as red meat, fish, poultry, dairy, tofu, tempeh
  • protein powders
  • high-calorie mass gain powders
  • breakfast cereals
  • cereal bars
  • fruits and vegetables
  • high carb dishes
  • baked goods
  • pizza
  • pasta
  • nuts and nut butters
  • cheeses
  • whole eggs
  • avocados
  • fast food

Foods to avoid

  • low calorie, diet, or sugar-free foods
  • foods that may cause negative health effects when eaten in large quantities, such as liver, Brazil nuts, and mercury-containing fish

Most foods are permitted while following a dirty bulk, though you may want to restrict some for various reasons.

While dirty bulking can be quite effective for gaining weight, its unrestrictive nature can lead to negative health effects.

For those looking to gain muscle mass without excessive amounts of body fat, there is an alternative to dirty bulking, which is often referred to as “clean bulking” or simply “bulking.”

When following a clean bulking approach, the goal is still to eat a calorie surplus with plenty of protein, though high calorie, processed, sugary foods are restricted.

A calorie surplus of 500 calories is usually a good place to start to promote muscle gains (2).

The majority of the diet is made up of calorie- and nutrient-dense whole foods, such as rice, nuts, nut butters, red meats, salmon, dried fruit, avocados, healthy cereals, whole eggs, and full-fat dairy products.

Some ways to ensure a sufficient calorie intake on a clean bulk include loading up on healthy fats, increasing your portion sizes, and surrounding workouts with plenty of carbs.

To ensure progress, it may be helpful to track your macronutrient intake — the protein, carbs, and fat you eat — and your weight to make adjustments to the diet as needed.


Considering that a dirty bulk can lead to excessive fat gain, some people may want to try a “cleaner” approach to bulking that omits processed, sugary foods and replaces them with calorie- and nutrient-dense whole ones.

A dirty bulk refers to a period of aggressive weight gain used to promote muscle and strength gains in strength sports and certain team sports.

Considering that a dirty bulk usually includes high calorie, processed foods, it comes with possible negative side effects, such as excess fat gain, sluggishness, and abnormal blood values.

Despite its possible downsides, a dirty bulk can be an effective weight gain strategy for certain populations, as it provides the calorie surplus necessary to gain muscle and strength, though it’s best followed as a short-term strategy.