You don’t necessarily HAVE to eat healthy to build muscle. As long as you strength train properly with sufficient calories and protein, your muscles should grow. This practice ignoring food quality to put on mass is called a dirty bulk—but it’s not without consequences.
If you’re familiar with my work, you already know I’m against the dirty bulk. It’s a sacrifice of one’s health for the convenience of lazy eating.
I understand that people want to gain muscle for their health and their looks. I prefer to look muscular and feel strong too. I also understand that it can be tempting to load up on burgers, fries, and sports drinks after a workout for less than the price of a gallon of gas, all in the name of more “gains.”
A dirty bulk can produce seemingly great results. Feeling like a bull, eating the whole buffet… What’s not to like? Everything but the actual gains, that’s what. A dirty bulk can lead to poor health outcomes, both now and (especially) down the road.
For instance: if you eat an electrolyte-poor diet, you’re asking for low energy, fatigue, muscle cramps, headaches, brain fog, and malaise. And electrolytes are just one class of nutrients. If I were to list all the possible imbalances and deficiencies that can result from dirty bulking, we’d be here a while.
I’m not trying to scare anybody. I’m just trying to emphasize the necessity of proper nutrition. We want a clean bulk, not a dirty bulk. And it’s not just about strength training, it’s about how you want to feel physically and mentally for the coming decades. With that, let’s dive into the basics of building muscle.
The Basics of Building Muscle
If you want to build muscle, there are three basic rules to follow:
- Consume enough protein
- Follow a well structured strength training regimen
- Adjust your calories as needed, depending on your body fat percentage
The current RDA for protein is 0.8 grams per kilogram body weight, but the science suggests this is probably too low for muscle gains. Anywhere from 1.0 to 1.6 grams per kilogram body weight is a better target for active folks.
For a 180 pound person, up to 160 grams of protein per day is considered safe. And so leaning towards higher intakes (150 to 200 grams per day) makes sense for bulking goals.
Bulking, in theory, requires a caloric surplus. If you want to add muscle mass, you need to eat more calories than you expend… But here is something people forget: Body fat is actually stored energy. So one really does NOT need an actual caloric surplus to gain muscle, unless one has very little body fat.
In general terms, I only suggest a caloric surplus of about 5 to 10% for people who are at a low body fat (BF) percentage: under 13% BF for males or 23% BF for females. People over those levels can eat at a slight deficit or maintenance, and gain lean mass without having to gain extra body fat.
Finally, the muscle tissue needs adequate stimulus to grow. That’s where resistance training comes in.
The best lifts for muscle gains are the big, compound lifts that work multiple muscle groups. Your best options are squats, deadlifts, power cleans, weighted pull-ups, bench press, overhead presses, and other Olympic movements.
A dirty bulk follows the three rules for muscle gains but overall, ignores food quality and quantity. And that’s a problem.
The Problems With a Dirty Bulk
A dirty bulk is a period of unrestricted feeding to support a strength training program. It’s a way to rapidly add mass without worrying about food quality.
If it has calories, it’s fair game for a dirty bulk. High-protein foods are emphasized (you can’t build muscle without amino acids like leucine)—but beyond that, the rulebook is thin.
As a result, the bodybuilders, powerlifters, and gym-goers that practice dirty bulking typically opt for the quickest, tastiest foods they can get their hands on. These binge-worthy calories might come from:
- Fried foods from a local fast food joint
- A box of cookies
- A ham, egg, and cheese bagel from the deli
- A loaf of cinnamon raisin bread
- Sports drinks
- Mom’s leftover pumpkin pie (all of it, not just one piece—sorry Mom!)
- Anything that comes in a package
There are many problems with eating this way, but they can be condensed into three main categories:
- Vegetable oils
- Nutrient deficiencies
Let’s unpack these now.
High-sugar diets (like the default American diet) are linked to almost every chronic disease in the book. The more sugar someone eats, the higher their risk for heart disease, obesity, type 2 diabetes, cancer, cognitive decline, kidney disease, and cavities.[*][*][*][*]
Let’s talk about the sugar-obesity link. (Obesity drives many of the other diseases.) Why does sugar make us fat?
For one, refined sugar (especially liquid sugar) doesn’t fill you up. It’s a source of empty calories. No matter how much you have, you always want more.
High-carb intakes also elevate blood sugar and insulin levels, creating conditions ripe for fat storage. In other words, a sugar-fueled bulk may promote muscle gain, but it will also promote fat gain.
#2: Vegetable oils
Speaking of fat gain, most processed foods contain vegetable oils like soybean oil, safflower oil, and others. High intakes of these omega-6 polyunsaturated fats (PUFAs) create inflammatory conditions that promote obesity.
Vegetable oils are especially dirty when heated (think fried foods). The cooking process destabilizes the fragile PUFAs, creating oxidized lipids that accelerate the progression of heart disease.
#3: Nutrient deficiencies
A dirty bulk ignores nutrients like fiber, vitamins, minerals, and essential fatty acids. If these nutrients happen to sneak in, it’s purely by accident.
But if you’re nutrient deficient, you won’t like the results. Consider a few examples:
- Magnesium deficiency is linked to higher rates of heart disease
- Inadequate fiber intake can cause constipation and elevated blood sugar
- Folate deficiency impairs energy production and reproductive health
There are dozens of more bullets I could list, but I want to move to solutions now.
Why Whole Foods Are Better
The solution is to get your calories from nutrient-dense whole foods. That’s a clean bulk. A clean bulk isn’t complicated. You just eat what Grandma would have eaten, but a lot more of it.
On a clean bulk program, you’re still consuming a calorie surplus, getting enough protein, and lifting weights. (The three rules of building muscle.) But this time, your calories come from whole foods sources like eggs, meat, fish, root vegetables, potatoes, fruits, and organ meats.
Real foods are nature’s optimal fuel. We evolved to eat them.
And they beat supplements any day. Real foods contain a wide spectrum of nutrients—vitamins, minerals, polyphenols, fiber, and fatty acids—that are best absorbed in food form.
Plus, it’s unlikely you’ll overdo any single nutrient in a whole foods diet. With supplements, it’s easy to slide into toxicity territory.
And did I mention…whole foods taste good? Once you start eating them, you’ll crave nothing else.
Obviously, not all whole foods support the cleanest of bulks. For instance, I don’t recommend the all-banana diet because that’s going to push your fructose intake into the stratosphere.
In fact, you don’t need carbs at all.
Can You Build Muscle on Keto?
The short answer is yes. Just follow my three muscle growth rules in the context of a clean keto diet.
Eating carbs is not one of those rules. In the absence of carbs, your body can make its own glucose AND its own muscle.
To be clear, if your goal is to add mass as quickly as possible, carbs are your friend. Carbs promote the release of insulin, a potent growth and nutrient storage hormone. And also, for some insulin-sensitive, lean individuals, you can practice a Targeted Ketogenic Diet approach (TKD) where you consume some high glycemic carbs around your workout. In a way, you can get the best of both worlds.
But if your primary goal is body recomposition (fat loss with muscle gains), I recommend limiting carbohydrate intake to a point. Keeping carbs low keeps insulin low, which helps you burn more fat.
That’s how I instruct my clients in my coaching career: it’s less about bulking and more about body composition. It’s worked for thousands of people, and it starts with a nutritious diet.
The Importance of Electrolytes
I can’t talk about strength training, keto, or any combination without talking about electrolytes. These minerals are essential for feeling and performing your best in these situations.
Proper hydration for strength training is all about replacing what’s lost through sweat. Mostly, that’s sodium and fluids.
The solution is simple: add salt to your water bottle and drink to thirst before, during, and after training. If you want it to taste good, use LMNT.
Along with sodium, potassium and magnesium are also critical for strength training. For example, up to 30% of the population may be magnesium deficient, and research suggests that correcting this deficiency improves strength and power.
Most of your potassium and magnesium should come from dietary sources. That means eating electrolyte-rich foods like dark leafy greens, meat, fruits, and root vegetables.
Talk about beating a dead horse. Yes, I’m recommending more whole foods. I’m recommending the opposite of a dirty bulk.
A Clean Bulk Every Time
You don’t have to eat clean to build muscle. You can get colossal on a steady diet of pure garbage.
But getting big shouldn’t be the only consideration. What about feeling clear and focused? What about keeping your heart healthy? What about aging more slowly? The quality of your food and its nutrient density matters.
Still, even if you care only about appearances, a low-carb clean bulk is better for that too. A dirty, sugary bulk adds muscle AND fat. My approach (let’s call it “lean gaining”) allows you to stay fairly lean while you are building muscle. Plus, the traditional approach where you bulk and then eventually have to “cut” is a drag for most people—especially after you have been bulking for several months.
The benefit of a lean gain approach is that you basically eat “the same” healthy foods, just a bit more of them in some cases, and you continue to practice the healthy habits that are needed to sustain the fat loss and muscle gains for years to come.
If you’re going to bulk, a clean bulk beats a dirty bulk every time. But you already knew that, didn’t you?