Busted: The “One Diet That Fits All” Myth

As a fitness professional, one question you will likely get asked more than any other is which “nutrition camp” you fall into. Are you into Paleo? What about vegan? Intermittent fasting?

Those are probably the wrong questions to ask in the first place.

It is time for you learn a new question, and discover what “camp” one should belong to.

The bottom line: You really shouldn’t fall into any single “diet camp.”

Unfortunately, this confuses many coaches and clients, because the human brain likes easy categorization.

You shouldn’t practice or teach only one style because there’s not a single, absolutely, positively, without-a-doubt, best diet for every person to follow, always, and forever.

Spend enough time actually working with clients and you’ll probably start to feel the same way too.

You can imagine the diversity.

  • Body type: Some clients are tall and thin. Others are short and stocky.
  • Dietary preferences & exclusions: Some clients like to eat lots of meat every day. Others prefer eating no meat at all.
  • Budget: Some clients have only a low budget. Others have unlimited food expense funds.
  • Organic / conventional: Some clients eat only boxed and packaged foods. Others will eat only organic, whole foods.
  • Nutrition knowledge: Some clients are devout followers of a certain dietary practice. Others will have very little nutrition knowledge whatsoever.
  • Time: Some clients have an open schedule, ready for any kind of health and fitness project. Others have a crowded daily schedule and countless conflicting priorities.

You get the picture.

There’s simply no way you’d be able to help all those folks make incremental improvements in their eating if we were militant about a single nutrition paradigm.

Imagine hearing this…

“I know you have a super-low budget for food. But if you sell your vehicle, you’ll be able to afford the organic and free-range whole foods we recommend in our program. That’s the only way to get healthy and fit.”

“Carbs? You’re not alone. We all like ‘em. But this program is all about cutting way back. Low carb is what works, period. Insulin is the enemy. So say goodbye to pasta. Potatoes too. And rice. And sugar…”

“Sure, I understand the moral and ethical obligation you feel. But eating animal foods…that’s how we do it. You need the protein and the fat. And it’s how our ancestors ate. So suck it up, throw a steak on the grill, and let’s get this party started.”

While these responses are a little extreme, they’re not that far from what top trainers hear every day in the gym or read on Facebook.

And it’s a shame because…

The best coaches don’t actually have a single nutrition philosophy.

Sure, if a particular nutrition idea — like Paleo or vegetarianism — worked for you personally, that’s awesome. You should be happy you found something that helped you reach your goals and/or aligns more closely with your values.

But to suggest that because it worked for you, at one point in your life, under a particular set of circumstances, now everyone else should follow the same program isn’t just narcissistic.

It’s the antithesis of good coaching.

Physiologically, the human body can do well under a host of different nutritional conditions.

This is clearly demonstrated by examining the traditional diets of various tribes and ethnic groups throughout the world.

For example, the Arctic Inuit and African Masai eat traditional diets that are very high in fat and animal products with very few vegetables.

Conversely, the Kitavans in the South Pacific eat traditional diets that are low in fat but very high in vegetables and starchy carbs.

And the !Kung of Africa eat traditional diets that are made up of mostly nuts and seeds.

Vast differences here.

Yet nearly all traditional diets seem to result in minimal incidences of cardiovascular disease, stroke, diabetes, and obesity.

Or consider the Blue Zones, pockets of the world where people seem to live measurably better.

While there is some basic nutritional overlap, each style of eating is different, while still resulting in successful health outcomes.

This is only possible because the human body is amazingly adaptable to a host of different dietary conditions.

It is possible to be healthy and fit whether you eat mostly meat or mostly veggies, mostly fat or mostly carbs, many times a day or just a few times, and so on.

Which means that, as a nutrition coach, you shouldn’t really belong to any specific nutrition camp at all.

When you work with actual human beings, you must be a nutritional agnostic.

Open to evaluating anything and everything that could work.

Willing to test new methods, even if they fly in the face of current beliefs or practices. And express the humility to sometimes be wrong, even if you really like being right.

If you believe too strongly in any particular “nutritional religion,” you fixate on the food itself.

Or…your own personal way of looking at food.

And you lose focus on what’s most important as a coach: Your clients and their individual physiological and psychological needs.

But wait…how can all these different diets actually work?

You’re probably wondering: How can such wildly different nutrition programs all lead to positive results?

Answer: They’re not as different as you might think.

Most effective nutrition programs are more similar than different (Yes, even Paleo and plant-based eating).

When done properly, Paleo diets, plant-based diets, high carb diets, low carb diets, eating small meals frequently, eating larger meals infrequently, all accomplish the following:

They raise nutrition awareness and attention.

Everyone wants to talk about the food itself — the proteins, carbs, and fats. What to eat more of and what to avoid. But research is now showing that simply paying better attention to what you eat is a key factor in whether you’ll lose fat, get lean, and improve your health.

Whether your attention is trained on avoiding carbs, eating more vegetables, seeking out organic/free-range food, avoiding animal foods, or avoiding “non Paleo” food, it’s all good.

Because what you focus on may not matter as much as simply caring more about what you’re eating in the first place.

Focus on food quality.

Paleo and low carb advocates want you to eat more natural, free-range animal-based foods that are higher in protein, higher in fat, and are minimally processed.

Vegan and high carb advocates want you to eat more natural, plant-based foods that are higher in fiber, antioxidants, and are minimally processed.

Recognize what’s common here?

Indeed, very few nutrition camps recommend you eat more processed, nutrient-depleted pseudo-food.

Instead, pretty much every camp recommends eating whole, minimally processed, nutrient-rich foods.

Foods that our bodies have a longstanding relationship with.

And this may be one of the most important nutrition interventions of all, regardless of the protein, carb, and fat breakdowns.

They help eliminate nutrient deficiencies.

In keeping with the last point, the best nutritional advocates help us shift away from highly processed foods, which are often low in nutrients because they’ve been stripped out during processing, and toward a variety of more whole, minimally processed foods, which often have their nutrients intact.

Thus, a properly designed diet of any kind eliminates some of the most common nutrient deficiencies (water, certain vitamins and minerals, proteins, and essential fatty acids).

A key component of this is dietary variety.

Some foods are lower in amino acids and some are higher. Some foods are lower in vitamins and some are higher.

No single food is meant to meet all of our nutrient needs.

We often look, feel, and perform terribly when we’re deficient in important nutrients. But within a few weeks of correcting these deficiencies, we feel totally rejuvenated. And because the transformation is so dramatic, that’s often when we become diet zealots.

They help control appetite and food intake.

When we’re more aware of what we’re eating, choose a variety of more satisfying, higher quality foods, and eliminate nutrient deficiencies, we almost always end up eating less total food. We feel more satisfied. We lose fat, gain lean muscle, and perform better.

Notice that you don’t need calorie counting here.

Focusing on food awareness and food quality is usually enough for people to tune into their own hunger and appetite.

And that means calorie control without the annoying calorie math.

It also means more sustainability since counting calories has a shelf life.

No one does it forever.

They promote regular exercise.

When people start paying attention to their eating, they usually start thinking about physical activity too. In fact, many of the diet camps recommend regular exercise. Which is a good idea, since focusing on diet alone may actually interfere with establishing a consistent exercise routine.

When a person exercises regularly, with a mix of high and low intensity activity, they dramatically improve their ability to turn the food they eat – whatever food that is – into functional tissue instead of extra fat.

You can now understand how different well-designed dietary philosophies – even when they seem oppositional and antagonistic on the surface – can all promote good health, body composition, and longevity.

Which is why…

Choosing a single diet camp makes no sense.

Hopefully you can now see that...

There’s no such thing as one, universal “best” diet.

There’s no one absolutely, positively, without-a-doubt best diet for everyone.

New headlines will continue to pop up about “which diet is best,” but remember, the existing knowledge base we have is more than enough to act on.

Humans have evolved to do well under all sorts of dietary conditions.

That’s why you should be happy to help people find the best one for them, no matter their dietary preferences.

This is a big win for your clients: They get in shape doing more of the things they actually like.

And a win for you: You get to help more people.

Are you interested in taking your knowledge of nutrition to the next level? Check out the ISSA Nutritionist program to earn your nutrition certification from the comfort of your own home.

John Berardi


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