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Dirty Bulking — and Why You’re Better Off Going Clean

This no-rules bodybuilding ‘diet’ comes with big risks

Bodybuilder drinks protein shake while sitting on weight bench with various hand weights in the background.

If you’re into fitness (or pay any attention to health advice) you probably know the basics of how we build muscle. Eat healthy foods. Exercise regularly. Sleep well. Those things you hear over and over and over again.

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But some people, particularly in the bodybuilding, weightlifting and extreme strength communities, are turning to some counterintuitive measures to improve fitness results. And with potentially dangerous consequences.

What’s their advice? Eat anything (and everything). As much as you want. And then some. Without considering its nutritional value.

It’s a concept called “dirty bulking.” And it’s gaining traction.

“Dirty bulking is a pretty hot topic in bodybuilding circles these days,” says sports medicine physician Michael Dakkak, DO. “It comes from the old adage, ‘If you want to get big, you got to eat big.’ But from a health standpoint, there are risks to that. And research has shown dirty bulking is unlikely to get you the results you’re looking for.”

Here, Dr. Dakkak explains dirty bulking, its risks and advice for bulking up in a healthy way.

What is dirty bulking?

Dirty bulking is a no-holds-barred approach to eating, with the ultimate goal of building muscle. It’s pretty normal for bodybuilders to purposefully gain weight in the off-season. But people who follow a dirty bulking practice will aggressively go way (way) over their normal calorie intake.

We’re not talking about a slice of cake after dinner here. We’re talking ice cream sundaes for breakfast. Footlong Italian subs every hour on the hour, washed down with a couple of sodas. Whole pepperoni and sausage pizzas with a party-size bag of chips on the side. Full-on extreme eating to the eleventh degree.

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“If you’re dirty bulking, you’re not considering the quality or nutritional density of a food, but rather just laser-focused on overconsuming calories,” Dr. Dakkak explains. “There’s no consideration for macronutrients. It’s just eating at will whatever your heart desires — and then some.”

The entire point of the bulking phase is to gain weight. People who choose to dirty bulk aim to gain faster. However they can. Whether they’re hungry or not.

Why?

Those excess calories turn to fat. And that excess fat can (in theory) be burned to fuel your workouts as you head into competition season.

“Following a phase of bulking, athletes cut their diet and buckle down on their training. That leads to a negative energy balance, which promotes muscle growth and fat oxidation,” Dr. Dakkak further explains.

The idea is to use that increased weight (“bulk”) to power your training and improve your physique — and, therefore, your success — in your competition season.

The idea of bulking is a pretty standard and accepted part of the life of a competitive weightlifting or bodybuilding athlete. But Dr. Dakkak says that the theory of dirty bulking doesn’t really hold up to scrutiny.

Should you try dirty bulking?

As much as you may have hoped eating anything you want was a legitimate route to a healthy body and improved athletic performance, that’s just not the way the cookie crumbles. (Sorry.)

“It’s no secret that excess calories lead to weight gain,” Dr. Dakkak notes. “Those excess calories are deposited as fat tissue in the body. And we know that excess fat can contribute to heart disease, high cholesterol and other conditions.”

What’s more, going through periods of eating a slew of highly processed and packaged foods can leave you at risk for vitamin deficiencies. Not to mention stomach aches, low energy and low testosterone.

But, you may be thinking, it’s only for a short time. I’ll go back to watching my diet like a hawk and heavy-duty lifting when I prepare for competition. It’s worth the tradeoff.

Beyond the health concerns of over-consuming, Dr. Dakkak says dirty bulking hasn’t been shown to have the promised athletic benefits either.

A study of 600 elite athletes looked at muscle mass, fat mass and performance between groups who increased their calorie count versus those who maintained a regular diet.

  • They showed no difference in muscle mass.
  • They both improved the weight they were able to lift at the same rate.
  • The group that over-ate increased their fat mass by 15%, while the group that maintained their diet increased their body fat by just 2%.

In other words, the group that was attempting to eat their way to muscle growth gained fat instead. And they didn’t improve their weightlifting ability.

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“I look at a study like this, and it’s proof that we shouldn’t be promoting dirty bulking,” Dr. Dakkak states. “It increases your fat and your risk of chronic disease without any improvement in performance. There are just too many risks without enough benefits.”

Better ways to bulk

The bulking phase is a pretty typical part of the training regimen for elite power athletes. But Dr. Dakkak says, it doesn’t need to be extreme to be beneficial.

“Think of your body like a car,” he illustrates. “When you’re driving a premium car, it deserves premium gas. You need the best fuel to power your body for optimal performance.”

What should a healthy off-season “bulking” diet look like?

“It’s a matter of being strategic about your consumption,” Dr. Dakkak advises. “For an off-season and pre-contest diet, you do want to increase your fat consumption and have some extra fat to burn. But that doesn’t give you free rein to eat everything in sight.”

A typical (so-called “clean bulking”) diet should include:

  • 50% carbohydrates. And stick mostly to complex carbs, like leafy greens and fruits.
  • 30% protein, mostly from lean sources like chicken, fish, beans, whole grains and soy.
  • 20% fat. Unsaturated fat is best. Good fat sources include things like olive oil, avocados, nuts and seeds.

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Dr. Dakkak recommends all athletes looking to maximize their performance see a specialized healthcare provider, like a sports medicine physician or dietitian, to evaluate their diet and training program. They can provide personalized recommendations based on your goals.

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