Introduction

When we launched this podcast back in 2008, I never imagined I’d still be here 16 years and 800 episodes later. It’s been such a great challenge and privilege to be in this role, helping you make sense of nutrition science, sift through diet trends, learn healthy nutrition facts and build a healthier relationship with food.

Consistency over the years

Over these years, I think my approach and philosophy has stayed relatively consistent—it’s always been about cutting through the noise to zero in on the things that actually matter, and translate them into practical advice. But the world of nutrition science? That’s a different story. We’ve come a long way, baby.

Significant shifts in nutrition science

So today, to mark this milestone, I want to take a look back at five of the most profound shifts in how we understand food, health, and nutrition since this podcast began—starting with the rise and fall of low carb diets.

The rise and fall of low carb diets

In 2008, low-carb diets were all the rage. Atkins, who originally put low-carb dieting on the map, had been joined by other low-carb diets like the South Beach Diet and the Dukan Diet. And the ketogenic diet was beginning to make waves. The idea of cutting out carbs to lose weight and improve health was incredibly compelling to many people—and in some cases, effective.

In an interesting side note, a recent study published in the Journal of the Academy of Nutrition and Dietetics found that among people who say they follow a low-carb diet, when you actually analyze their dietary records, fewer than 2% of them actually do. So, while it once seemed like everyone was on a low-carb diet back then—in reality, almost no one actually was.

Fast forward to today, and while keto still has its devotees, low-carb diets have largely fallen out of favor. But they’ve left their mark on the way we think about food—and not necessarily in a positive way. One lingering misconception from the low-carb era is the way we use the word ‘carbs’ to refer almost exclusively to starchy foods like bread and potatoes. In fact, some of the healthiest foods in our diets—fruits and vegetables—are virtually 100% carbohydrates. We’re still working on rehabilitating that word (and nutrient) from the low carb days.

The rise of protein

Another big shift over the last 16 years has been the rise of protein from a background player or afterthought to center stage. In 2008, protein was seen as important for athletes and bodybuilders, but for the average person, it wasn’t a major concern.

In episode 67 of the podcast, Monica asked “Can eating more protein help you eat less, lose weight, and build more muscle?” Listen to what she had to say in the player below.

Today, we have a greater appreciation for the essential role that protein plays, not just in building muscle but for healthy aging, metabolism, appetite control, and even bone health. We now recognize that getting adequate protein, particularly as we age, is crucial for maintaining muscle mass and preventing frailty. There are even researchers petitioning the government to increase the recommended daily allowance for protein for certain populations.

The focus on protein has predictably led to an explosion of high-protein snacks, shakes, and fortified foods. And, it’s gotten pretty ridiculous: you can now buy high protein water, coffee, even beer! But the protein craze has also run head-long into another major trend: the move toward plant-based or plant-forward eating for environmental or ethical reasons.

Now, it is absolutely possible to meet your protein needs with plant-based sources. However, plant-based sources of protein generally deliver significantly less protein–and more calories–per serving. It can also take more total plant-based protein to equal the higher biological availability of animal-based proteins. So, those trying to leverage the advantages of a higher protein diet on a strictly plant-based diet will definitely have to do a little more planning than those who are willing to incorporate animal sources, which can also include eggs, dairy, in addition to meat, poultry, and fish.

While I think the current protein craze will eventually calm down a bit (it’s hard to believe that high protein beer is really here to stay), I think our expanded appreciation of protein’s role in a healthy diet–particularly for older individuals and others at risk of muscle loss–is here to stay.

Nutrition Diva episode 699 made Monica ask, “Are we eating too much protein?” Hear her answer in the full podcast, which you can listen to in the player below. 

Understanding the microbiome

Another huge shift in the way we think about diet and nutrition has been the explosion of research and interest in the microbiome. My own nutrition education (in the aughts) focused primarily on how food interacted with our bodies: our metabolism, our digestive system, our organs, and tissues. The idea that food might also be affecting trillions of microbes living in our gut–and that they, in turn, were basically running the show–wasn’t really part of the conversation.

Today, we understand that our microbiome plays a crucial role in digestion, immunity, metabolism, and even mental health. We also now recognize that what we eat has a direct impact on the health and composition of these microbial communities. And this has completely changed how we think about certain foods.

For example, we used to look at fiber mostly in terms of its effects on digestion and regularity. Now, we understand that fiber is actually food for beneficial gut bacteria—helping them thrive and, in turn, supporting our overall health. And what foods are highest in fiber? Fruits, vegetables, legumes, and whole grains—all of which happen to be carbohydrate-rich foods.

In fact, this may have been one of the final nails in the low-carb coffin. As our appreciation for gut health grew, so did our awareness that carbohydrate foods are the sole source of fiber—a critical component of a healthy microbiome. Suddenly, cutting out entire food groups didn’t seem like such a great idea anymore.

In 2022, Monica went into detail about a recent study that added to the debate about artificial sweeteners and whether they help or hurt with weight loss. Hear all about it on episode 682. Listen by clicking on the player below. 

The rise of the microbiome has also driven interest in probiotics, fermented foods, and even personalized nutrition based on gut bacteria analysis. While some of these trends are grounded in solid science, others have outpaced the research and become overhyped. Not every probiotic supplement is helpful. Not every gut microbiome test can provide meaningful insights. But the fundamental shift remains: our understanding of nutrition now goes beyond just how nutrients affect our tissues to how our food affects the ecosystem inside us.

Advancements in personalized nutrition

And speaking of personalized nutrition, this is another realm that has been utterly transformed in the time I’ve been doing this podcast. Sixteen years ago, personalized nutrition centered around things like the Blood Type Diet or those somewhat silly plans that were based on whether you were shaped like an apple or a pear.

Fast forward to today, and the concept of personalized nutrition has become much more sophisticated—at least in theory. Advances in genetic testing, microbiome analysis, and continuous glucose monitoring (CGM) have made it possible to collect vast amounts of individualized data. The promise is that by analyzing this data, we can tailor diets to optimize health, prevent disease, and even improve athletic performance.

While there’s exciting potential in these technologies, the reality is that much of personalized nutrition is still in its infancy. Direct-to-consumer DNA tests may tell you whether you have a genetic variant that affects how you metabolize caffeine or store fat, the effectiveness of dietary prescriptions based on this information is not well established. Similarly, while CGMs can provide interesting insights into how different foods impact blood sugar levels in various scenarios, they’re being marketed to populations that don’t have diabetes, in ways that may not be particularly useful.

The idea that we can (or should) be tailoring diets based on a microbiological analysis of a stool sample is also still far ahead of the science. The composition of the gut microbiome fluctuates daily, and we’re still learning what a truly “optimal” microbiome looks like–much less how to manipulate it.

That’s not to say personalized nutrition isn’t valuable—it absolutely can be, especially for managing certain conditions or optimizing athletic performance. And I don’t doubt that these technologies will continue to evolve in ways that might make them much more useful in the future.  But right now, I think that we’re a little bit out over our skis on this.

Transformation in understanding obesity

And the final change that I want to mention may be the most impactful of all. Sixteen years ago, obesity was primarily framed as a lifestyle issue, something that could be solved with the right combination of willpower, diet, and exercise. While we certainly recognized that genetics and metabolism played a role, the prevailing narrative was that weight loss was simply a matter of eating less and moving more.

Today, our understanding of and approach to obesity has been completely transformed by the rise of GLP-1 receptor agonists—drugs like Wegovy and Mounjaro. These medications, which help regulate appetite and metabolism, have not only been a game-changer for people who have struggled for years to lose weight and keep it off but have also transformed our understanding of obesity as a complex, chronic disease.

Obesity rates have now declined (slightly) for the first time ever. Snack food companies and fast-food operations are seeing a decline in sales. And the list of other medical conditions that may be positively impacted by these medications includes everything from kidney disease to sleep apnea to alcohol use disorder. I can’t really think of another pharmaceutical advance in my lifetime that has had this scale or scope of impact–one that we’re probably still too close to fully appreciate.

In episode 684, Monica covered sweetened cereals and their connection – or lack thereof – to obesity. Listen to the whole episode in the player below. 

Thoughts on the future

Looking into the future, I sense that we are entering a period where we’re going to be seeing a lot more innovations that will profoundly transform our understanding and approach to nutrition and health. For example, I think we are going to see more widespread adoption of groundbreaking new food technologies—things like lab-cultured meats, bioengineered fats, even 3-D printed foods.

These kinds of things may sound futuristic or even a bit unwholesome to us now. But on a rapidly warming and increasingly crowded planet, these types of technological breakthroughs could play a key role in creating a more sustainable and secure food future.

Either way, as this brave new world unfolds, we’ll navigate it together. Thanks for being along for the ride—especially those of you who have been listening since episode 1!

To listen to the first episode of the Nutrition Diva podcast, listen in the player below!