Brian St. Pierre

Meet the Experts

Brian St. Pierre



Brian St. Pierre is the director of nutrition at Precision Nutrition, the coauthor of Precision Nutrition’s Level 1 Certification textbook, The Essentials of Nutrition and Coaching, and the mastermind behind the Precision Nutrition Calculator. He holds a master’s degree in Food Science and Human Nutrition from the University of Maine.

St. Pierre is a Registered Dietitian (RD), Certified Strength and Conditioning Specialist (CSCS) through the National Strength & Conditioning Association (NSCA), and a Certified Sports Nutritionist (CISSN). He also serves on the Men's Health Network (MHN) Board of Advisors.

During his time at Precision Nutrition, St. Pierre has provided nutrition coaching and performance meal planning to US Open champion Sloane Stephens and a host of other professional and Olympic athletes. He’s also served as a nutrition consultant for the NBA’s San Antonio Spurs and Brooklyn Nets and the NFL’s Cleveland Browns.

Prior to joining Precision Nutrition in 2012, St. Pierre was the head sports nutritionist and a strength and conditioning coach for Cressey Sports Performance, a high-performance facility in Hudson, Massachusetts and Jupiter, Florida.

A leading expert in teaching nutrition coaching skills to fitness professionals, St. Pierre has presented hundreds of workshops and trainings in five countries and 17 U.S. states. He’s been featured in US News & World Report, Men’s Health, Men’s Fitness, ESPN the Magazine, Shape, Q Magazine, STACK, and Testosterone Magazine and his insights have been included in stories on,, BuzzFeed, and more.

Twitter: @bspnutrition
LinkedIn: brian-st-pierre-ms-rd-cscs-b2a19519b

Articles by Brian St. Pierre, MS, RD

Woman eating a bowl of fruits.

Carb cycling: Is this advanced fat loss strategy right for YOU?
(Take the quiz.)

Here’s everything you need to know about this popular nutrition strategy.

Horizontal chart of different potato and sweet potato meals shown from eat more often on the left to eat less often on the right.

Sweet potatoes vs. potatoes: Which are really healthier? [Infographic]

Sweet potatoes vs. potatoes: A nutritional debate fueled by misinformation, baseless ‘superfood’ obsessions, and carbohydrate phobias. Here’s how these tubers compare — and why both deserve a place in your diet.

Male athlete with a prosthetic leg in an explosive running position on an outdoor running track.

The new rules of sports nutrition: This could revolutionize the way you coach athletes.

Sports nutrition is about more than biochemistry and advanced training plans. Here’s how to help your clients get to the next level.

The Ultimate Macro Calculator

Do you want to lose weight? Gain muscle? Improve health? Boost performance? This free calorie, portion, and macro calculator from Precision Nutrition can help you achieve the results you want.

Disappointed man wearing swim trunks holding a fitness magazine.

Fat loss hacks!?!? 10 charts show why you don’t need them.

Most “diet hacks,” “fast fixes,” and “easy solutions” make fat loss even harder than it needs to be. Here’s what you can do instead.

Man pressing cellphone between ear and shoulder, holding a notebook looking confused.

Meal plans usually suck.

Lots of people looking to improve their eating think meal plans are the answer. The only problem? Meal plans usually suck... and they rarely last. So, instead of prescribing yet another doomed eating regimen, check out these 6 ways to transform any diet in a sustainable way.

Chart with illustrations of different food options for lean proteins, smart carbohydrates, and healthy fats.

‘What should I eat?!’ Our 3-step guide for choosing the best foods for your body. [Infographic]

This easy-to-use visual guide shows you how to make healthier nutrition choices, and determine the best foods for your body, goals, and taste buds. In fact, our simple three-step process helps you create a customized healthy-eating menu in just a matter of minutes. And the best part: Nothing’s off limits.

Man standing on white digital scale, from man's point of view.

Can eating too little actually damage your metabolism?

There’s a lot of discussion in the fitness industry about whether crash dieting can cause metabolic damage. In this article, we’ll take on this interesting topic and separate fact from fiction. We’ll also teach you exactly why crash diets might be linked to struggling to maintain your weight in the future.

We’ve told 100,000 clients, “There are no bad foods.” And we’re not about to stop. Here’s why.

Our stance tends to spark lots and lots of questions, which is why this article takes a deep dive into the whole “good foods vs. bad foods” debate.

The modern diet dilemma: Is it better to… eat meat? Go vegan? Something in between? The truth about what’s right for you.

The vegan vs. meat-eater debate is complex. Consider these pros and cons when deciding whether to go vegetarian, whole-food plant-based, or vegan.

Fat loss and muscle gain: What does realistic progress look like?

How fast can a client lose fat? What's the upper limit for muscle gain? We have the numbers—and your coaching game plan. 

Macros vs. calories vs. portions vs. intuitive eating: What’s the best way to ‘watch what you eat?’

Should you count calories and macros? Estimate your portions? Try intuitive eating? Use this guide to get the results you want, gain a better relationship with food, and make healthy eating seem effortless.

‘What should I drink?!’ Your complete guide to liquid nutrition. [Infographic]

Consider this graphic the uncomplicated answer to every question you’ve ever had about what to drink (including how much, when, and why). And here’s a surprise: You don’t have to swear off the drinks you love in the name of better health and nutrition. Instead, use this guide to make beverage choices that are just a little bit better, one step at a time.

Can you gain weight from eating too little? No, but here’s why it’s so easy to think you can.

You’re tracking your eating and exercise meticulously but not seeing results. Has your metabolism slowed to a crawl? Are your hormones off? Is it really possible to GAIN weight from eating too LITTLE? Here’s what’s really going on — and how to solve it.

Eating too much?
You can blame your brain.

Forget willpower: Brain signals drive what, how, and when we eat. If you’re eating too much, here’s how to take back control.

Precision Nutrition’s
Weight Loss Calculator

This weight loss calculator (based on the NIH Body Weight Planner and adapted from research collected at the National Institute of Diabetes and Digestive and Kidney Diseases), factors in how your metabolism really works to predict how long it’ll take to reach a particular weight loss goal.

The power of sleep. [Infographic]

If your eating and exercise are on point, but you still don’t feel or look the way you want, poor sleep may be to blame. Here’s how to tap into the power of sleep and make rest a daily priority.

The best calorie control guide. [Infographic]

Head swimming with calorie numbers and daily allowances? Trust us…there's a better way to measure your portions. Try this calorie control guide. It's practical, powerful, and proven with over 100,000 clients

Settling the great grain debate.

Are grains saving your life—or trying to kill you? In this article, we'll discuss both sides of the debate. We'll also leave you with some actionable steps to start eating better immediately.

A muscular man holding a bowl of muesli standing in front of his supplements

Best workout nutrition strategies.

Looking for the best workout nutrition strategies to help improve performance, drop body fat, and gain lean muscle? Look no further. This article will teach you what to eat before, during, and after exercise for your specific goals.

It won’t kill you to grill.

Worried about grilling and cancer? Don’t let the fearmongers fool you. Check out these ingenious ways to grill for your health.

The Paleo problem:

When it comes to nutrition, were our ancient ancestors smarter than we are? Proponents of the popular Paleo diet say yes. But what does it take to eat like a cave man (or cave woman) – and will it really result in better health? Brian St. Pierre reviews the latest research and reveals some nuggets of good sense in the midst of the Paleo propaganda.

Coffee… upgraded?

Bulletproof Coffee has become something of an internet sensation. People are talking about it. People are trying it. Many even claim it works wonders for them. What is it about this magical concoction that has people pimping up their cup of joe? More importantly, do the results actually match the hype? Brian St. Pierre finds out.

Workout nutrition explained.

For most people, nutrient timing isn’t all that important. But if you’re an athlete or serious exerciser, peri-workout nutrition – or what you eat before, during, and after a workout – can powerfully affect body composition, recovery, and adaptation. Find out what, when, and why to eat to perform your best.

Is nutrient timing dead?

For the past two decades, nutrient timing has been a hot topic in sports and exercise nutrition – seeming to answer many questions about weight loss, body composition, and health. But is it really as important as it seems? Brian St. Pierre examines the latest evidence, showing us why it’s high time we lost our obsession with timing.

Carb controversy:

Yes, we've all heard about how carbs: spike your blood sugar and insulin - causing fat gain - lead to all sorts of inflammation, and aren't even essential nutrients, like fat and protein. And, yes, the anti-carb folks are pretty vocal about this stuff. But these are only half truths. So, in this article, I'll share the whole truth. I'll even help you find the right amount of carbs...for you.

Surprising supplements

While some supplements are useless, and some may be downright dangerous, others show proven benefits to human health and performance. Surprisingly, some of the best remain relatively unknown. In this informative article, Brian St. Pierre examines the evidence in favor of several lesser-known supplement stars.

Hacking sleep:

Most of us understand that sleep is crucial to health. Yet night after night we toss and turn, hitting the snooze button when the alarm begins to ring. Luckily, just a few simple changes to our routines can help us reverse these patterns and ensure that we get the truly restful sleep our bodies and minds deserve.

Eliminating jet lag:

Nobody enjoys feeling disoriented, nauseated, tired, and unable to concentrate or sleep. But with a few simple precautions, you can vastly reduce your symptoms and enjoy a smoother transition, whether your trip is for business or pleasure.

All About Eating Slowly

The benefits of eating slowly include better digestion, better hydration, easier weight loss or maintenance, and greater satisfaction with our meals. Meanwhile, eating quickly leads to poor digestion, increased weight gain, and lower satisfaction. The message is clear: Slow down your eating and enjoy improved health and well-being.

Safe household cleaners:

Many popular cleaning products contain dangerous chemicals that can damage our health and the environment. But, armed with the information in this article, you can choose safer alternatives that are just as effective.

Safe cosmetics

Personal Care products and cosmetics contain many chemicals that can contribute to environmental damage and that may affect our health. What’s more, the chemical industry is largely unregulated. That’s why it’s important to do research in order to protect yourself, your family, and our planet. Luckily, small changes can really make a positive difference.

Indoor air pollution:

Indoor air pollution can be a serious - and potentially deadly - problem. But a few simple tricks can reduce your risk, protect your health, and safeguard the health of your family.

All About Healthy Condiments

Can food taste good and still be good for us? The PN chefs think so! Nutrient-packed condiments can make food delicious while still keeping us healthy and lean. Find out how to choose and prepare the best condiments -- from pesto to hummus to salad dressing.

Environmental toxins:

Environmental toxins are cancer-causing chemicals and endocrine disruptors that can harm our health by disrupting sensitive biological systems. Here, we review what endocrine disruptors are, where they come from, and how to minimize exposure.

All about coffee:

Coffee is among the most consumed -- and controversial -- beverages in the world. While coffee should be treated with care and avoided altogether by those who metabolize it poorly, it also provides health benefits to many people. Find out what they are – and how to drink coffee responsibly.