In our last basic nutrition tips article we talked about using the simple tool of using your hand to measure appropriate food portions and ditch weighing a measuring food in many contexts. This weeks article is actually inspired by a client that brought a hot nutrition debate topic to me in an email article (linked) and made me realize that many of you who read this may also have been seeing this information.

In the ever-evolving field of nutrition science, a recent study published in Nature Metabolism has stirred the pot by shedding light on the amino acid leucine (one of 9 essential amino acids) and its potential dual role in our health. What the authors of the study consider a revelation has sparked a conversation that's as rich and complex as our diets themselves; yet in the end it may not be so complex. Let's dive into the meat of the matter, shall we?

Leucine, long hailed as an "essential amino acid" for its muscle-building capabilities, has now been tagged by some researchers as a "pathogenic amino acid." This provocative label stems from findings suggesting that while leucine stimulates muscle growth through mTOR activation, it might also encourage atherosclerotic plaque growth in our arteries. The study suggests that the same threshold of leucine intake needed to boost protein synthesis could also heighten cardiovascular disease risk by fostering an pro-atherogenic environment.

Points and Counterpoints in Nutritional Science

Recently taking to critique this article was Chris Masterjohn (amongst many others), a respected voice in the field of nutrition, offering a critical perspective on these findings. He argues that the study's focus on mechanistic data overlooks the broader physiological context. Yes, leucine activates mTOR in immune cells, potentially leading to atherosclerosis in the study design, but it also plays pivotal roles in muscle growth and immune function which may overshadow and fail to show a complete picture due to the mechanistic data being paired with hard to relate mice studies. Masterjohn critiques the study's experimental design, particularly its reliance on highly processed protein sources, and emphasizes that real-food contexts didn't change the outcome; the animal models being used not being relevant to humans, and the mechanistic data doesn’t translate well. Furthermore, the study may misrepresent data it cites.

I look at Chris’ critiques and add that arguments for negative health consequences about nutrient types can also be made about carbohydrate and fat if looking at mechanistic studies also. That would leave us nothing safe to eat!

This discourse highlights a fundamental truth about nutrition science: it's a field rich in debate, with each study contributing to an intricate puzzle where there are no “free lunches” and the bigger picture is usually quite complex. As we uncover more about how individual nutrients affect our health, we're reminded of the complexity of human biology and the interplay of various metabolic pathways.

A Nuanced Outlook on Nutrition

What does this mean for you and me? First and foremost, it underscores the importance of a balanced, nuanced approach to nutrition. While high-protein diets, particularly those rich in leucine, have their place, especially for muscle synthesis and recovery in most people, this new research invites us to consider cardiovascular health implications as well. It does not mean we need to change course though. While it is one study, it may warrant further exploration in order to either explore more nuance or perhaps debunk totally. Personally, I am not quite sure more research will be in alignment based on how the findings came about; but I’m open to being persuaded down the line. Again, one study in a field of numerous others that do not demonstrate an issue is one to approach with caution. Also to note again is that this study used animal model data and techniques that may not represent human physiology very well at all.

The conversation between proponents and critics of high-protein diets illustrates a crucial point: the science of nutrition is never black and white. It's filled with gray areas that require further exploration and understanding in the full context of complex human physiology. As such, more research is almost always needed (all the time!), with each study adding a piece to the vast mosaic of nutritional knowledge.

Interestingly, in Masterjohn’s critique, he also plugs a fasting protocol for sale by him. This is not a critique of Chris, but it does raise hairs of suspicion even in a critique.

Personalized Nutrition: The Key to Long-Term Health

In navigating this complex landscape, the best approach to nutrition is deeply personal. What matters most is finding a nourishment habit that resonates with your body's needs, preferences, and your lifestyle. It's about striking a balance that supports both your physical health and your sense of well-being.

For some, this might mean moderating certain foods. For others, it could involve integrating other food types, diversifying protein sources, or perhaps even staying the course if already happy and healthy with what you are doing. The goal is to craft a diet that fosters long-term health, vitality, and satisfaction based on your body.

Embracing a Lifestyle of Informed Eating

As we continue to navigate the evolving landscape of nutrition science, let's do so with open minds and a commitment to informed eating. By staying abreast of the latest research, engaging in thoughtful discussions, and tuning into our bodies' signals, we can make dietary choices that serve us best without getting too bogged down by either data or anecdote.

Remember, we are more than just bags of protein. We need protein for…

1. Muscle Repair and Growth: Protein is the building block of muscles. It aids in the repair of muscle tissues that are damaged during exercise, supporting muscle growth and strength. This is crucial for athletes, bodybuilders, and anyone engaging in physical activities.

2. Hormone Regulation: Proteins play a pivotal role in hormone regulation, particularly those involved in the coordination of bodily functions like metabolism and stress response. For instance, insulin, a hormone that regulates blood sugar levels, is a protein.

3. Enzyme Functions: Enzymes, which are proteins, catalyze most of the biochemical reactions in our bodies. They facilitate crucial processes, including digestion and energy production, ensuring our body's proper functioning.

4. Immune System Support: Antibodies, which help fight infections, are made of proteins. A sufficient protein intake ensures a robust immune response, protecting the body against pathogens and illnesses.

5. Transport and Storage of Molecules: Proteins are essential in transporting and storing various substances throughout the body. Hemoglobin, a protein in red blood cells, transports oxygen from the lungs to the body's tissues and returns carbon dioxide from the tissues back to the lungs.

The journey to optimal health is a personal one, filled with learning, growth, and occasional recalibration. We need to embrace this journey with curiosity, compassion, and a spirit of discovery, crafting a nourishment path that truly fits our individual lives. If we knee jerk every time a new article comes out, then we “lose sight of the forest for the trees”.

If you need help figuring out what will work best for your body and goals, we have been helping folks from all walks of life for many years do just that. We will have some more spots opening for our holistic health coaching program right around the corner in Spring 2024. If you want to take the guesswork out of nutrition and what will work best for you and your wellness goals, we would love to help you!

Sign up here for a consult to reserve a spot:

https://app.acuityscheduling.com/schedule.php?owner=20706020&appointmentType=17238949

Sources cited:

https://chrismasterjohnphd.substack.com/p/will-eating-protein-wreck-your-arteries?

https://www.nature.com/articles/s42255-024-00984-2