If you give too much credence to mainstream diet trends, you’re pretty much doomed.

Maybe you’ll identify with the Paleo culture and become convinced that eating like a caveman is the way of the future. Or maybe you’ll jump on the “carbohydrates are the source of all your weight loss woes” bandwagon and subscribe to ketogenic dieting. Maybe you’ll take it a step farther with more extreme things like cleanses, unclogging hormones and biohacking.

The truth is: There is no “one true diet.” While this concept doesn’t have the sizzle to sell millions of books and millions in supplements, it works.

What is the truth about dieting?

It has several parts, or tiers, and can be envisioned as a pyramid of descending importance that looks like this:

  • Energy Balance
  • Macronutrient Balance
  • Food Choices
  • Nutrient Timing

Let’s look at each of the layers in detail.

No. 1: Energy Balance

Energy balance is the overarching principle of dieting. This dictates your weight gain and loss more than anything else.

Energy balance is the relationship between the energy you feed your body and the energy it expends. This is often measured in kilocalories.

The bottom line is that meaningful weight loss requires you to expend more energy than you consume, and meaningful weight gain (both fat and muscle) requires the opposite—more consumption than expenditure.

A century of metabolic research has proven, beyond a shadow of a doubt, that energy balance, operating according to the first law of thermodynamics, is the basic mechanism that regulates fat storage and reduction.

No. 2: Macronutrient Balance

Next on the diet pyramid is macronutrient balance. In case you’re not familiar with the term, the dictionary defines macronutrient as “any of the nutritional components of the diet that are required in relatively large amounts: protein, carbohydrate, fat and minerals such as calcium, zinc, iron, magnesium and phosphorous.”

You’ve probably heard that “a calorie is a calorie,” and while that’s true for matters relating purely to energy balance and weight loss and gain, a calorie is not a calorie when we’re talking body composition.

Sure, you can follow Professor Mark Haub’s lead and lose weight by eating nothing but protein shakes, Twinkies, Doritos, Oreos and Little Debbie snacks. But we don’t want to just gain and lose weight. Our goal is more specific: We want to gain more muscle than fat and we want to lose fat, not muscle. And with those goals, we have to watch more than just calories. We have to watch our macronutrient intake too.

If you want to go beyond “weight loss” and learn to optimize your body composition, the macronutrient you have to watch most closely is protein. Your carbohydrate and dietary fat intakes can be all over the place without derailing you, but eating too little protein is the cardinal sin of dieting for us fitness folk.

  • Eat too little protein while restricting your calories for fat loss and you’ll lose a significant amount of muscle as well. (This is why weight loss isn’t enough. Lose muscle and you lose weight, but you’re going backward in your quest to build an impressive physique.)
  • Eat too little protein while eating a surplus of calories to maximize muscle growth and you’ll build less muscle. This is one of the reasons “bulking” has a bad rap. When done improperly, it packs on way more fat than muscle and is counterproductive in the long run.

What is too little protein?

  • If you’re relatively lean and aren’t dieting for fat loss, you should set your protein intake at 0.8 to 1 gram of protein per pound of bodyweight per day.
  • If you’re relatively lean and are dieting for fat loss, you should increase your intake slightly to 1 to 1.2 grams per pound of bodyweight per day. (Research shows the leaner you are, the more protein your body will need to preserve muscle while in a calorie deficit for fat loss.)
  • If you’re overweight or obese, your first priority should be fat loss, and your protein intake should be set at 1 to 1.2 grams per pound of lean mass per day.

No. 3: Food Choices

There are no such things as “weight loss” or “weight gain” foods. They are figments of diet hucksters’ imaginations. As Professor Haub showed proved, you can lose fat eating whatever you want so long as you regulate your intake and maintain a state of negative energy balance. However, certain foods make it easier or harder to lose and gain weight due to their volume, calorie density, and macronutrient breakdown.

Generally speaking, foods that are “good” for weight loss are those that are relatively low in calories but high in volume. Examples of such foods are lean meats, whole grains, many fruits and vegetables and low-fat dairy. These types of foods also provide an abundance of micronutrients, which are especially important when your calories are restricted.

Foods not conducive to weight loss are high in calories and low in volume and satiety. These foods include caloric beverages, candy, bacon and other sugar-laden goodies. Quite a few “healthy” foods fall into this category as well: oils, butter, low-fiber fruits, and whole fat dairy products, for example. The more we fill our meal plans with calorie-dense, low-satiety foods, the more likely we are to get hungry and overeat.

As a rule of thumb, if you get the majority ( approximately 80 percent) of your calories from unprocessed, nutrient-dense foods, you can fill the remaining 20 percent with your favorite dietary sins and be as healthy, muscular and lean as ever.

No. 4: Nutrient Timing

Last on the pyramid is nutrient timing—and the simple fact is: How often you eat and when you eat do not really matter.

Increasing meal frequency doesn’t speed up your metabolism. Eating carbs at night doesn’t make you fat. The “anabolic window” is more fiction than fact.

One of the many beauties of our bodies is they are incredibly good at adapting to meet the physical demands we place on them, and so long as you get the other points of the pyramid right, you have a lot of leeway here at the bottom.

That said, I do think it’s worth noting that there is evidence that eating protein, in particular after a workout, is better for long-term muscle growth. Personally I play it safe and eat about 40 grams of protein within an hour of weightlifting, and I’d recommend you do the same.

The Bottom Line

If you’ve struggled to find a diet that actually works, you now know the way.

Learn how to manipulate energy balance, keep protein intake high and adjust carbohydrate and fat to meet your needs and preferences, eat a wide variety of nutritious foods “supplemented” with some indulgences, and eat on a schedule you prefer, and you’ll never look back.

Learn more about Mike Matthews’ line of 100% science-based workout supplements and custom meal plan service to help you build muscle and lose fat.