Should your calories come from clean foods, dirty foods, or does it not even matter? Bulking up requires a calorie surplus, and the faster you want to gain weight, the bigger that calorie surplus will need to be. But where should those calories come from?
There are two popular approaches:
- Clean bulking: where we get our calorie surplus from healthy foods, building our muscles out of high-quality calories.
- Dirty bulking: where we eat whatever we want whenever we want, gaining weight by whatever means necessary.
Now, there’s also the If It Fits Your Macros (IIFYM) approach, where you eat the correct number of calories and the correct proportion of macronutrients. However, some people follow IIFYM while dirty bulking, others follow it while clean bulking. It’s a whole separate thing.
I started off severely underweight, and over the course of gaining sixty pounds, I’ve tried both clean and dirty bulking. In fact, I’d credit each approach with around thirty pounds of my overall gains. I’ve failed with both approaches, too.
Then, over the past eight years, we helped nearly 10,000 other skinny guys bulk up, as well as our millions of readers. We’ve watched them use a variety of different approaches, we’ve listened to horror stories, and we’ve celebrated too many successes to count. Seeing so many different people bulk up has added nuance to our opinions over the years.
There’s also quite a lot of research looking into how our food choices affect our ratio of muscle-to-fat gains while overeating. And this research is rarely brought up when discussing the pros and cons of each approach.
So. What’s the best bulking diet? Should we bulk clean or dirty?
- Dirty Bulking
- Clean Bulking
- Should Skinny Guys Bulk Clean or Dirty?
- Main Takeaways
What is Dirty Bulking?
Dirty bulking is when you try to gain weight by whatever means necessary. You might also hear it referred to as a “see-food diet” because it means eating everything in sight. For example, it might include lots of pizza, chicken wings, juice, and weight gainers—plus a second helping of dessert.
- Emphasis on high-calorie foods, whether they’re nutritious or not.
- Emphasis on gaining weight by whatever means necessary.
- Nothing is off the menu.
Dirty bulking was made famous by Westside Barbell powerlifters like Dave Tate, who would order a few McDonalds burgers with hashbrowns for lunch, and then snack on pizza drenched with olive oil before dinner. Not surprisingly, these guys were notorious for becoming both astonishingly strong and shockingly fat. Many of them also ran into health issues and had to turn things around.
Some bodybuilders dirty bulk as well, but since bodybuilding centers around being lean, they’ll often try to keep their body-fat percentages under control. As a result, bodybuilders are more famous for taking the clean approach to bulking, as we’ll cover in the next section.
Most importantly, when it comes to us skinny guys, most of us will at some point experiment with an all-out max-calorie dirty bulk, gain too much fat, spend a couple of months cutting, and then never do it again. In fact, it’s such a common feature in our transformation stories that we almost consider it a rite of passage.
After all, those dirty bulks are often responsible for helping us defeat our skinniness once and for all. In my case, I had to spend three months cutting in order to get back down to 10–11% body fat, but once I did, it became evident that I had gained quite a lot of muscle while dirty bulking:
Is Dirty Bulking a Good Way to Bulk Up?
Dirty bulking has a few advantages, especially for skinny guys who are having trouble gaining weight:
- Junk food is less filling per calorie, making it easier to eat enough calories to gain weight (study).
- Processed foods are essentially predigested, putting far less strain on our digestive systems—at least in the short term.
- Eating a totally unrestricted diet is simple and enjoyable.
However, dirty bulking has a few disadvantages as well:
- Processed food is often high in dietary fat, which can make us gain more body fat (study).
- Processed food is often overly high in saturated fat, which can make us gain even more body fat (study).
- Diets that are overly high in added sugars could also potentially cause us to gain more body fat (study).
- Our digestive systems may get weaker over time if we aren’t eating the fibre, prebiotics, and probiotics that are found in fruits, veggies, and dairy.
- If our diets are low in vitamins, minerals, and immune-system boosting foods such as garlic, then we might get sick more often (study).
- Gaining fat while eating poor quality foods is going to cause a disproportionate amount of visceral fat gain, which can be harmful to our longterm health (study, study).
One interesting thing about dirty bulking, though, is that the disadvantages can be mitigated by being more active and doing more cardio.
The more cardio you do while bulking up, the more visceral fat you’ll burn for energy, and the healthier your body-fat storage patterns will become (study, study, study, study). That may do a pretty good job of offsetting the harms of a diet that’s too high in saturated fat or sugar.
The more active you are while bulking up, the higher your energy flux (g-flux) will be. The more you move around, the higher your metabolism will be. That means that you’ll need to eat more food to gain weight. And because you’ll be eating more food overall, each calorie won’t need to be as dense in micronutrients, giving you much more flexibility with your bulking diet.
Overall, this makes dirty bulking more appropriate for guys who are quite active and are having trouble eating enough calories to gain weight.
Does Dirty Bulking Cause Faster Weight Gain?
I did some googling around before writing this article, and one of the big claims out there is that dirty bulking causes guys to gain weight more quickly. That’s not entirely accurate.
If someone is on a diet where they eat ad libitum then, yes, dirty bulking will often cause them to gain weight more quickly. After all, when people eat whatever they want, they tend to gravitate towards:
- Foods that taste better.
- Foods that have a higher energy density.
- Foods that digest more quickly.
This drives them into a larger calorie surplus, causing them to gain weight more quickly. But make no mistake, it’s the calorie surplus that’s causing the weight gain.
Now, our specialty is helping skinny guys bulk up. And we skinny guys, of course, are all about gaining weight quickly. We don’t want to be skinny any longer than we need to be. So this is an important point.
We tend to run into two issues:
- We eat whatever we want and we don’t gain any weight.
- We eat as much as we possibly can, we go overboard, and we get fat.
In the first case, we fail to gain weight because we aren’t eating enough calories. Our food choices only matter insofar as they help us reach our calorie goals more easily.
In the second case, we get fat because we’re eating far too many calories. Our food choices might play a small role in causing extra fat gain, but the majority of the fat gain is due to our uncontrolled calorie intake, not because of our food choices.
If we start associating weight gain or fat gain with our food choices, we’re going to get confused about the role of calories, and our bulks are going to go sideways.
Don’t get me wrong, food choices do matter. But you can gain fail to gain weight while dirty bulking, and you can get fat while clean bulking.
Will You Gain More Muscle by Dirty Bulking?
Similar to gaining weight, the amount of muscle that you gain isn’t always directly related to your food choices. However, dirty bulking will often help skinny guys gain weight faster, and the faster we can gain weight, the more muscle we can build—to a point.
If our circumstances allow us to gain, say, a pound of lean mass per week, but we’re only eating enough calories to gain half a pound, then we’ll be building muscle at half speed. That’s perfectly fine if you aren’t in a hurry, but most of us skinny guys are eager to not be skinny anymore. So we bulk more aggressively, we drive ourselves into a bigger calorie surplus, and we gain weight more quickly.
I mean, even if we aren’t lifting weights, around 33% of the weight that we gain is lean. That means that if you’re gaining two pounds per week, you’d be gaining as much as 0.7 pounds of lean mass every week. That would be a tremendous rate of growth, surpassed only by your appalling rate of fat gain.
However, there are limits to how quickly we can build muscle. Eating in a larger calorie surplus will eventually just start adding extra fat into the mix. Furthermore, some guys might be able to gain 0.7 pounds of lean mass in a week while only gaining 0.5 pounds overall (due to simultaneous fat loss).
Now, what does this have to do with dirty bulking? Not that much. So long as your diet isn’t disastrous, your rates of muscle gain will largely be determined by how new you are to lifting, how far away from your genetic potential you are, how good your hypertrophy workouts are, how good your bulking macros are, and how well you’re sleeping.
How much sugar and grease you have in your diet is a factor as well, but just one of many.
Is Dirty Bulking Unhealthy?
Dirty bulking isn’t inherently unhealthy. In fact, it even has some advantages over clean bulking. For example, this 1991 study found that trying to eat clean places so many restrictions on food choices that it can cause our diets to become unbalanced, leading to nutrient deficiencies.
How can that be, though? Aren’t clean foods more nutritious per calorie? Perhaps the participants ate plenty of leafy greens, which is wonderful, but perhaps it made their diets too high in fibre overall, causing some digestive issues. Or maybe they found themselves craving chocolate-covered peanuts because their bodies were looking for a good source of zinc, but they resisted that craving because those chocolate-covered peanuts are “dirty.”
There was another old study that found that people who were given unrestricted access to a full refrigerator were able to prevent deficiencies by simply trusting their cravings.
When dirty bulking, we’re freer to follow our cravings, including our cravings to eat a wider variety of foods—including junk foods—which can paradoxically give us a more balanced intake of nutrients overall.
You could say that when it comes to our guts, we should trust our guts.
What’s the Best Dirty Bulking Diet?
Dirty bulking can be unhealthy and fattening, but many of those disadvantages can be avoided by adopting a more moderate approach.
Instead of replacing all of the food that we’re eating with junk food, perhaps we still start our days off with a smoothie, we still have a sandwich for lunch, we still snack on some trail mix, and we still eat a regular dinner. But then we also have whatever we want for dessert, we don’t shy away from ordering pizza some nights, we use plenty of sauces on our foods, and we have a weight-gainer shake after every workout.
That would give us a foundation of nutritious foods, which would remove most of the downsides of dirty bulking. And then we’d have some dirty bulking strategies thrown on top, which would help us gain weight more easily.
As a general rule of thumb, most health institutions recommend keeping your added sugar and saturated fat intakes to under 10% of your total calories (each). A simple way to do that is to aim to get 80% of your calories from whole foods.
However, you can also build a good weight-gain diet entirely out of whole foods. Here are some great bulking foods that are also healthy. And we’ve got an entire article about how to eat more calories.
What are the Best Dirty Bulking Foods?
The best dirty bulking foods are the ones that make it easier to gain weight, that are unlikely to cause fat gain, and that won’t harm our long-term health.
- Pizza: It might sound like junk food, but pizza is made out of flour, tomato sauce, cheese, and toppings. There’s nothing inherently unhealthy about those ingredients. If your pizza is topped with veggies instead of processed meat, it’s actually a pretty high-calorie and nutritious bulking food.
- Olive oil: Dirty bulkers are known for drizzling olive oil on top of everything (including pizza), which is a great way to add tons of highly nutritious calories to your diet. The trick is to make sure that your overall fat intake isn’t more than around 30% of your total calories, which is when your muscle gains might start becoming less lean.
- Hamburgers: ground meat is easier to digest than steak, which makes it great for gaining weight. You can add some eggs, onions, and even oats into the patties as well. It gets better, too: the buns add in starchy carbs, toppings often include fresh vegetables, and any sauces that you add will only raise the calorie content even higher.
- Maltodextrin: adding maltodextrin to your post-workout protein shakes is a great way to add a ton of starchy carbs into your diet.
- Chicken wings: chicken wings are high in protein, rich in nutritious connective tissues, and also contain some unprocessed fat sources. I coat them with brown sugar and hot sauce, bake them in the oven, and then dip them into a sauce made from Greek yogurt and blue cheese. (Here’s a good recipe.)
- White rice or pasta: one of the biggest problems with dirty bulks is that they wind up being too high in dietary fat, which is a surefire way to gain a ton of body fat while bulking. You’ll make leaner gains if you hammer home the starches instead.
Now, you might say: but those foods aren’t even dirty! And you’d be right. That’s kind of the whole point. A good “dirty bulk” will still be built around whole foods, it’s just that those foods might include some refined flour, indulgent amounts of cheese, some sauces with added sugar, and so on.
Some dirty bulking diets are going to include Pop-Tarts, potato chips, and fast food. Those can be fine in moderation as well. But any good bulking diet will still be built on top of a strong foundation of whole foods.
What is Clean Bulking?
Clean bulking is when you try to gain weight by eating minimally processed “clean” foods. For example, someone eating a clean diet might avoid deep-fried foods, processed vegetable oils, simple carbs, and added sugars. They might focus instead on eating plenty of chicken, spinach, broccoli, oatmeal, and nuts.
- Emphasis on choosing nutritious foods.
- Empty calories are seen as bad.
Clean bulking has been popular in the bodybuilding scene for decades now, with bodybuilders being infamous for bringing Tupperware containers to restaurants, avoiding alcohol and desserts at celebrations, and even carrying around their bulking meals in fanny packs.
Is Clean Bulking a Good Way to Bulk Up?
Clean bulking definitely has some advantages, especially for skinny-fat guys who are having trouble keeping their gains lean:
- Whole foods tend to be more filling per calorie, making it harder to get into a calorie surplus, and thus making it harder to gain weight too quickly.
- Unprocessed foods are harder to digest, keeping us fuller for longer, and causing more calories to be burned off as body heat instead of being stored as fat (or muscle).
- Nutritious foods seem to result in leaner muscle gains (study, study).
- When body fat is stored, it tends to be subcutaneous, which isn’t as harmful to our longterm health (study, study).
- Furthermore, if we’re consuming more nutritious fats, then our body will store those more nutritious fats as body fat. Again, this can be better for our longterm health. This is why you’ll hear bulking experts such as Mike Israetel, PhD, recommending that if guys want to maintain good general health while bulking up, they should be eating plenty of nutritious fats, such as nuts.
- Eating diets that are rich in fibre, prebiotics, and probiotics tend to be good for our digestive systems, which will make it easier to bulk up in the longer term, as well as to maintain our higher body weights.
- Eating a 100% clean bulking diet is strict but also simple, which can make it easy to adhere to.
Clean bulking has some disadvantages as well, though:
- Many people find clean bulking to be an unsustainable way to eat. After all, it can be difficult to have a rich social life when your diet is incredibly strict.
- There’s no proven advantage to eating 100% clean diets when compared against diets that are made up of around 80% whole foods.
- Many of the rules that clean bulkers adhere to, such as avoiding simple carbs, don’t make very much sense—especially in the context of bulking.
- It can be very difficult to gain weight while eating a 100% clean bulking diet.
What’s nice about clean bulking is that your diet can offset some of the harms of being less active overall. Since you’ll be storing less fat, and especially less visceral fat, then it’s not as important to be burning it off through added exercise.
To be clear, the World Health Organization recommends lifting weights and doing cardio. So for optimal health, even with a great diet, we’d still want at least that baseline level of exercise. If you’re right up against that lower threshold, though, or if all you do is lift weights, then eating a cleaner bulking diet may help.
Does Clean Bulking Yield Leaner Gains?
While getting my lay of the land, I noticed another big claim: that clean bulking causes leaner gains. That isn’t necessarily true, and we’ve seen a lot of skinny-fat guys led astray by this falsehood.
So, first of all, we’ve already discussed some mechanisms through which clean bulking can lead to leaner gains. Keeping our overall fat, saturated fat, and fructose intakes under control can help. So can ensuring that we eat enough protein every day. And eating foods that aren’t as processed can raise our metabolisms (since those foods require more energy to digest). Furthermore, getting more overall vitamins and minerals in our diets tends to be a good thing for both our general health and for muscle growth.
However, we can’t make the mistake of thinking that eating a clean diet will necessarily lead to lean gains. Clean bulking and lean bulking are not the same things. They just rhyme.
I’m going to write a whole article about lean bulking versus aggressive “bear-mode” bulking, but in the meantime, let’s use an example.
Let’s imagine a dirty bulker. Maybe he gets into a calorie surplus by having some cherry pie after dinner every night. That cherry pie contains 500 calories, which is (theoretically) enough to gain around a pound per week.
Now let’s imagine a clean bulker. Maybe he gets into a calorie surplus by having a giant breakfast smoothie made out of spinach, oats, nuts, yogurt, and protein powder. Let’s say that this smoothie adds 1,000 calories into his diet, which is (again, theoretically) enough to gain around two pounds per week.
Which bulker will make leaner gains? In this case, the dirty bulker is eating in a smaller and more reasonable calorie surplus (for most skinny lifters). The clean bulker, on the other hand, is going overboard on the calories.
Calories tend to matter more than food choices, so even though the clean bulker is making healthier food choices, we’d expect him to gain more fat.
Then, because good body composition is so crucial for our general health, we’d also expect the dirty bulker to wind up healthier by the end of his bulk.
However, if both bulkers were eating a smart 500-calorie surplus every day, then we’d expect the dirty bulker to gain weight a little bit more quickly (because his diet requires less energy to digest), and he may also gain a little bit more fat, and his general health might not be quite as good (depending on the rest of his diet).
So clean bulking can result in leaner gains, but it doesn’t always. In fact, if you aren’t making lean gains, your food choices probably aren’t even a good first place to look.
What’s the Best Clean Bulking Diet?
Clean bulking has the right spirit. It can help us build muscle more leanly, it’s good for our digestive system, and it’s good for our longterm health. Most people who try clean bulking experience some of these benefits and enjoy it.
The problem is, as skinny guys who already have a hard timing gaining weight, clean bulking is only going to that even harder. Our digestive systems will struggle to digest all of the fibre, leaving us feeling bloated and gassy. We’ll need to force-feed ourselves in order to hit our calorie goals, making our diets totally unsustainable. And we won’t build more muscle or store less fat than people taking a more moderate approach.
We prefer to build our diets out of a healthy foundation, but then to relax about the details. If the majority of our breakfasts, lunches, snacks, and dinners are fairly nutritious, then we don’t need to worry about sauces, a little sugar in our coffees, a serving or two of dessert, an indulgent Sunday brunch, having a beer after work, or the occasional pizza.
Furthermore, it’s important to keep in mind that when we’re bulking, we have an abundance of calories coming in. Because of the sheer volume of calories that we’re eating, not every single one of them needs to be rich in nutrients. Not every one of them needs to contain fibre. And it’s okay if some of them are “bad” calories.
Because the majority of the food we’re eating is nutritious, we’ll still get all of the vitamins, minerals, fibre, prebiotics, probiotics, and phytonutrients that we need to maintain good health.
For example, as we mentioned in the previous section, most major health institutions see absolutely no problem with getting up to 10% of our calories from added sugar. Furthermore, that’s extremely unlikely to cause extra fat gain, and it might even increase the rate that we can build muscle (study).
To be clear, though, we do recommend getting at least 80% of your calories from unprocessed whole foods. If you have trouble gaining weight without relying on processed foods, we’ve got an entire article about how to eat more calories.
What Are the Best Clean Bulking Foods?
We’ve written an entire article about great bulking foods that are also healthy, but here are a few good examples of clean bulking foods:
- Trail mix: nuts and dried fruits are two of the most energy-dense whole foods, making them great for gaining weight. Furthermore, trail mix usually includes a mix of several different nuts and dried fruits, providing a wide variety of vitamins and minerals.
- Muesli cereal: similar to trail mix, muesli cereal is made by mixing together a few different energy-dense bulking foods, such as oats, whole grains, nuts, and dried fruits. You can then add whole milk, raising the energy density even higher.
- Dairy: milk, cheese, yogurt, and whey protein are all rich in calories and nutrients, and they all count as minimally processed “clean” foods.
- Oats: oats are a great source of starchy carbs. The downside is that oatmeal can be quite filling, but blending them into smoothies tends to solve that problem.
- Smoothies: blending together oats, fruits, nuts, spinach, and dairy into a bulking smoothie is perhaps the single best way to add nutritious calories into your bulking diet.
- Chili (and other bulk meals): one of the easiest ways to eat a nutritious bulking diet is to prepare your meals in bulk and then store them in the freezer. Then, when you’re tired or busy, you can microwave a “clean” meal instead of ordering fast food.
Should Skinny Guys Bulk Clean or Dirty?
If you’re doing a proper dirty bulk, where no more than 20% of your calories are coming from junk food, that’s pretty similar to a proper clean bulk, with at least 80% of your calories coming from nutritious whole foods.
I know that’s a crummy answer. It’d be pretty stupid to say that both clean bulking and dirty bulking—done wisely—are exactly the same. However, they are both similarly effective, they’re just best for people with different issues.
Clean Bulking is Best for Rehabbing Bad Diets
Let’s imagine someone who eats a crappy diet. Maybe he grabs a sugary coffee and some pastries for breakfast, then has a deli-meat sandwich for lunch, and then heats up some frozen pizza for dinner. That diet is way too low in protein, fibre, and vitamins and minerals.
The foundation of this diet is weak. We shouldn’t build on it. If this guy starts dirty bulking by ordering extra pastries for breakfast and pouring olive oil on his pizza, it’s just going to make him skinny-fat.
A better approach for this hypothetical dude is to gradually swap out crappy meals for better meals. Maybe he buys a blender and starts making himself a breakfast smoothie that some fruits, nuts, spinach, oats, and a couple scoops of unflavoured whey protein in it. That’s going to add in a ton of protein, micronutrients, and calories.
Perhaps to fix his lunch, he starts getting his sandwiches on whole-grain bread, he chooses chicken breast instead of processed meat, and he adds some cheese and veggies to it. It’s a fairly small change that already fits into his routine, but it’s going to be adding more micronutrients alongside extra calories and protein.
Maybe to solve his dinner issue, he starts cooking up a big batch of chili, picadillo, stew, or lasagna. If he has a big pot, he can prepare 12+ servings at a time, giving him a stockpile of easy reheatable dinners that are more nutritious than the frozen pizzas he used to rely on.
This is how we turn a bad diet into a good, clean bulking diet.
Dirty Bulking is Great for People Who Already Eat Well
Now let’s imagine a guy who has some muesli cereal for breakfast, reheats some chili for lunch, and has those classic steak and potatoes dinners with a side of peas (or whatever).
This is a strong foundation that we can build on. This guy doesn’t need to take a clean approach to bulking, he just needs to add in more calories into his diet so that he can gain weight more easily.
In this case, maybe he wants to put some cream to his coffee, some dark chocolate chunks in his cereal, some olive oil on his chili, and then have a dessert after dinner.
Some of those extra calories are nutritious, which is great, but he doesn’t need to be strict about it. The main emphasis is on keeping the foundation strong while adding calorie-rich foods on top of it.
This is how we take a healthy diet and turn it into a killer bulking diet.
If it Fits Your Macros (IIFYM)
The other important thing to keep in mind is that whether you’re bulking clean or dirty, you need to make sure that your calorie intake is on point and that you’re consuming enough protein.
One of the best ways to blow a bulk is to add in a bunch of high-calorie foods, start gaining weight too quickly, gain a bunch of fat (simply because you’re eating too many calories), and then blame all that fat gain on your food choices.
Yes, food choices can play a role in the ratio of muscle-to-fat that you gain, but your calorie intake is far more important. If you’re gaining two pounds per week on the scale, you aren’t getting fat because your diet isn’t clean enough, you’re getting fat because you’re gaining weight more quickly than your body can construct muscle.
The other thing that will limit how quickly your body can construct muscle is not eating enough protein. You’ll want at least 0.8 grams of protein per pound body weight per day. So if you weight 150 pounds, that means eating at least 120 grams of protein every day.
In fact, most nutrition labels on foods are inaccurate, most protein powders contain less protein than they claim, and many skinny guys will fall short of their macro targets sometimes while bulking. To account for this, we often recommend aiming for a full gram of protein/lb/day.
Any talk of if it fits your macros, of course, needs a disclaimer. Macros aren’t all that matter. Food choices are indeed important. But we can’t let concerns about food choices eclipse the fact that our macros need to be in order.
A good bulking diet is made up of at least 80% whole foods. If your diet is worse than that, trying to clean it up while bulking is probably wise. But if your diet is already great, then enjoying more indulgences while bulking can be a great way to make gaining weight easier and more enjoyable.
Whichever approach you take, keep in mind that carbohydrates tend to be an asset while bulking, whereas diets overly high in fat can cause excess fat gain. Aiming to get 40–60% of your calories from carbohydrates is usually wise, with starchy carbs and fruits being the best carbohydrate sources. This means that clean bulkers might need to intentionally eat more rice, oats, and pasta, whereas dirty bulkers might need to keep an eye on their fat intake.
Finally, if you’re gaining fat while bulking, remember that the quality of the food that you eat isn’t everything. It could be that you aren’t following a good hypertrophy routine, maybe you aren’t eating enough protein, or it could be that your calorie intake is simply too high—you’re just gaining weight too quickly. Even chronically failing to get enough sleep can cause disproportionate amounts of fat gain.
If you’re having trouble managing all these different factors, check out our Bony to Beastly Bulking Program. We lay everything out in an easy-to-follow system. I’m not going to say that it will make bulking easy, but it will at least make it straightforward. We also include coaching, which will allow us to coach you through any struggles you run into.