Do your clients want to lose weight?

For most personal trainers, the answer is a pretty emphatic "yes."

Do they need diet and nutrition advice to make it happen?

Again, the answer is almost certainly affirmative.

But there's a catch: You've probably read or been told that diet and nutrition advice are outside a personal trainer's scope of practice. In fact, stepping out of your lane can even be illegal.

Is that true?

No. Personal trainers can and should talk to clients about what they eat, and suggest ways to improve their choices.

But there are limits to what you can and can't tell a client. And more important, you really need to know what you're talking about before you say anything.

That's what we'll tackle here.

READ ALSO: 5 Mistakes Trainers Make When Offering Nutrition Advice

Before we get into the details, I want to tell you a story about a good friend of mine, Gray Cook. You probably know him as the guy who created the Functional Movement Screen (FMS).

Gray was one of the first people to bring movement screening, corrective exercise, and dynamic mobility work into fitness.

At that time, in the early 2000s, those things were thought to be in the realm of physical therapy, and thus outside a personal trainer's scope of practice. But Gray started teaching these techniques to personal trainers.

Managers at gyms got angry. Trainers got nervous. Physical therapy organizations sent him cease-and-desist letters and lawsuit threats. It all went by the wayside because, fundamentally, these practices are all about movement, and movement belongs in the gym. Education won over fear and feudalism.

Today fitness professionals routinely include movement screening, mobility work, and corrective exercises as part of their workouts with clients. We're on much the same path with nutrition support.

The most educated and experienced coaches—the leaders in the fitness industry—understand they can't achieve the best results unless they coach the whole person. They know their training programs will be more effective if they consider their clients' lives outside the gym—their stress, their sleep, and, yes, what they eat or don't eat.

At the same time, many clients now expect nutrition advice. They expect you to answer their questions about their diet, and advise them on how to manage it.

You can and should have those conversations with your clients, as long as you respect these guidelines.

What personal trainers can't do when it comes to nutrition

To become an RD, you have to get a four-year college degree and log hundreds of hours in a rigorous internship. You don't just study nutrition; you also have to learn anatomy, physiology, and biochemistry. Then you typically train in a special area, like pediatric or geriatric nutrition.

After all that, you have to pass a licensure exam. Only then can you call yourself an RD, and only when you have those letters after your name can you offer medical nutritional therapy (MNT) to patients with conditions like diabetes.

If you're not a registered dietitian or medical doctor, you cannot:

• Prescribe diets or nutritional supplements to treat medical and clinical conditions.
• Prescribe diets to treat symptoms of medical and clinical conditions.
• Diagnose medical conditions.

To give you a practical example, let's say you have a client who's just been diagnosed with prediabetes. The client asks you for a diet to help him lower his blood sugar before it turns into type 2 diabetes. You're sure you can help him. But you can't. What he's asking for is technically MNT, and it's illegal for you to offer it unless you're a physician or RD.

Even something as simple and straightforward as offering a weight-loss diet for someone with obesity can be construed as prescribing, treating, or even diagnosing a medical condition, and thus outside your scope of practice.

READ ALSO: How to Help a Client Who Has Type 2 Diabetes

What personal trainers can do when it comes to nutrition

Each state or province has different rules and regulations describing what you can call yourself and what kind of advice you can give.

In general, a personal trainer can talk to clients about making healthy lifestyle choices. That means you can talk about food and eating behaviors in a variety of ways:

• Encourage clients to eat lean protein and nutrient-rich vegetables.
• Educate clients about the benefits of protein, healthy fats, and other macronutrients.
• Offer clients recipes or demonstrate food prep skills.
• Let clients know about evidence-based nutritional supplements that might augment their healthy lifestyle.
• Educate them about the pillars of good nutrition, and offer strategies to improve their eating habits.
• Help them choose the right foods to eat before and after workouts.
• Suggest they drink water to stay hydrated.
• Share resources from recognized nutrition organizations, including the Academy of Nutrition and Dietetics, American Heart Association, and Precision Nutrition.
• Present nutrition information in an accessible, down-to-earth way, one that engages them rather than making their eyes glaze over.

None of those would be viewed as diagnosing health problems or prescribing treatments for diseases or their symptoms.

What matters most is how you communicate with your clients. A few examples:

You CANNOT:

• Prescribe a diet to treat someone's obesity
• Offer a plan to manage blood sugar
• Recommend fish oil for treating arthritic knee pain

You CAN:

• Share a recipe for a tasty, high-fiber, slow-digesting meal
• Share evidence that fish oil supports healthy movement

See the difference?

In most places, you're allowed to talk generally about how nutrition supports goals like performance, health, and well-being. It's when you get into the specifics, in marketing or discussions with clients, that you risk crossing legal boundaries.

If you're not sure, don't guess. Check your state or provincial guidelines to find out what you can or can't say.

READ ALSO: Five Ways to Help Clients Lose Weight

None of this matters unless you know what you're talking about

We live in an age of instant experts. That's especially true of nutrition. But it's one thing to share opinions about the latest diet craze with your friends, and something else entirely when you offer advice to someone who's paying for your expertise as a fitness professional.

It's like someone looking at your car and saying, "Hey, you really should get that thing fixed," vs. that same person offering to fix it for you.

If you're going to present yourself as a credible, serious professional, you need to start with a realistic and accurate idea of how much you know, or don't know. The only way to be sure is to test your knowledge against objective, rigorous, evidence-based standards, such as the requirements for a nutrition certification. Without that, you're just guessing, and probably guessing wrong.

What kind of education is available for health and fitness professionals?

In most countries, the term "dietitian" is legally reserved for people who've completed the stringent RD program I described earlier.

At the same time, the term "nutritionist" is broader and loosely defined. It can include everything from a person with a PhD (like me) to someone who completed an online course in a single weekend.

While there isn't one particular nutrition certification you need, I'm obviously and understandably biased in favor of my own course, Precision Nutrition Level 1. It's rigorous and well-respected.

But whatever you choose, look for one that emphasizes coaching  techniques and change psychology. Why? Because understanding the science of nutrition won't get you very far if you don't have the foundational coaching skills you need to guide your clients toward habits and behaviors that'll actually stick.

READ ALSO: These Are the Best Advanced and Specialized Personal Training Certifications

Why it's important to talk about nutrition in the first place

In the last two sections, we talked about what health and fitness professionals can and can't do when it comes to nutrition.

While some people like to make the rules sound tricky and complicated, discussions like this often distract from the most important message:

We must do something.

I've been involved in health and fitness for 25 years, and I believe substantive, proven nutrition coaching is a missing component in the health, fitness, strength, and rehab fields.

Without effective nutrition coaching skills, health and fitness professionals struggle (and too often fail) to help clients achieve their goals.

Clients get frustrated and quit, and their health stagnates or gets worse. Failure affects coaches, too. They lose their passion, and start to look toward the exit to pursue another career.

Nutrition coaching skills help trainers feel confident and competent. You can answer your clients' questions clearly and effectively. You can demonstrate expertise and an authoritative command of the field. You can guide your clients toward real, noticeable, lasting change, rather than juggling a series of quick fixes. You can inspire your clients to change, rather than exhausting yourself with constant pushing and cajoling.

Most importantly, you can really, truly help your clients.

Wouldn't your clients be better off if they can get exercise, nutrition, and lifestyle advice from the same knowledgeable, trusted source?

In working with tens of thousands of clients over the past 10-plus years, I've learned that including nutrition in your practice can make you five times more effective. That means:

• 25 pounds lost, instead of five
• 20 points knocked off a client's blood pressure score, instead of four
• Five inches off someone's waist, instead of one

Five times more client commitment, confidence, motivation, retention, and satisfaction—with one-fifth the effort to make it happen.

Every client is different, with unique goals, needs, and challenges. But with the proper education and coaching skills, you can feel confident in talking about nutrition with them. You can offer suggestions you know are safe and correct, so your clients get the care they need.

The question of whether (or not) you should give nutrition advice is just part of a much larger, much more important question for the industry:

Will we start looking at clients as whole people whose health and well-being depend on movement, proper nutrition, stress management, better sleep, and a deeper connection to their community?

Or will we continue to take clients through workouts while ignoring all the other things that can make them happy, healthy, and whole?

I think the fitness industry is pointing toward the former. And this is the context in which nutrition advice is the most meaningful and effective.

READ ALSO: Why You Should Have Dinner with Your Clients

What to do next

If you're ready for the nutrition knowledge and coaching strategies to take your career to the next level, start here.

1. Understand what you legally can and cannot say

Remember: Only registered dietitians and medical doctors can provide medical nutritional therapy or prescribe nutritional interventions to treat medical or clinical illness.

So unless you have one or both of those credentials, don't try to use nutrition advice to diagnose or cure a health problem, relieve disease symptoms, or answer clients' questions about any of the above.

2. Decide what you want to be able to say, and why

There are many possible paths in nutrition education:

• Degree programs allow you to become a registered dietitian, teacher, or lecturer.
• General nutrition courses (quality ones) are for health professionals who want to be able to talk to clients about nutrition basics.
• Fitness nutrition certifications are for personal trainers who want to offer reliable nutrition advice to improve client results.

3. Choose how you'll study

Some questions to ask when you're looking at programs:

• Do I complete the course at home, or in a classroom?
• Are there specific times when I'll have to study?
• Is there a deadline, or can I complete the course at my own pace?
• Do I get to practice real-life client scenarios?

4. Weave in coaching and psychology

Having a handle on change psychology is crucial to helping your clients with nutrition. What they eat is deeply ingrained, and changing it can be a slow, difficult process unless you understand what makes your clients tick.

5. Find a mentor

If you want to keep growing and developing in your business and career, you need to find the right mentor.

A good mentor will provide the perspective you don't yet have, and help you stay confident and inspired, even when the going gets tough.

John Berardi’s latest book is Change Maker: Turn Your Passion for Health and Fitness into a Powerful Purpose and a Wildly Successful Career. A version of this article originally appeared at Precision Nutrition.