In the realm of nutrition science, individual differences are more profound and impactful than many realize. For decades, we’ve developed dietary recommendations with a “one-size-fits-all” approach, assuming that most people respond similarly to specific nutrients. But Dr. Martin Kohlmeier, a pioneer in precision nutrition, challenges this very notion.

How might an individual’s genetic makeup alter their need for certain nutrients?

With advances in nutrigenetics, we’re beginning to see how personalized nutrition could bridge long-standing gaps in dietary efficacy. Dr. Kohlmeier’s work highlights fascinating examples, from the APOE4 gene’s influence on cholesterol metabolism to variations in folate metabolism that could affect everything from heart health to birth outcomes.

As Dr. Kohlmeier explains, precision nutrition is not simply about adding genetic testing to a wellness regimen. Instead, it requires rethinking nutrition research from the ground up—ensuring studies capture these individual variations and that public health policy moves beyond broad averages.

With genetic testing now more accessible than ever, could commercial pressures and oversimplified testing derail the science before it even gets going? In this episode, we dive deep into the potential and pitfalls of precision nutrition, exploring the future of personalized dietary advice and the road to truly individualized health.

• [02:33] Introduction of Dr. Martin Kohlmeier and his background
• [05:10] Rethinking assumptions in nutrition science
• [07:42] The role of genetic variations in nutrient responses
• [13:15] Practical examples of genetic impact on nutrition
• [22:55] Misinformation and commercial misuse in nutrigenetics
• [29:48] Case studies: cholesterol sensitivity (APOE4) and folate metabolism (MTHFR)
• [41:03] Public health implications and the need for tailored research
• [49:27] Future directions and the path forward for precision nutrition

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• Kohlmeier, 2023 – One size does not fit all: on the need for categorical stratification in nutrition science, practice and policy

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In this episode, we dive deep into the world of ocular nutrition with Professor John Nolan, exploring how specific nutrients can play crucial roles in preserving eye health, improving vision and supporting cognitive function.

With age-related macular degeneration (AMD) affecting millions globally, Professor Nolan sheds light on groundbreaking research showing how certain carotenoids—natural pigments found in plant foods—could impact eye health and perhaps even neurodegenerative conditions like Alzheimer’s disease.

But what are these compounds exactly, and why are they so impactful?

Through in-depth clinical studies, Nolan has identified optimal nutrient formulations that could bridge the gap in conditions as diverse as macular degeneration and cognitive decline. He makes a compelling case for why the timing and quality of these interventions could matter as much as diet itself.

Finally, this episode goes beyond individual health to consider public health implications, particularly the need for better regulation in the supplement industry and enhanced nutritional education for medical practitioners.

• [01:20] Professor Nolan’s academic journey and early inspirations in vision science
• [02:12] Groundbreaking research on age-related macular degeneration (AMD)
• [04:24] How carotenoids contribute to eye health and disease prevention
• [07:27] Expanding from eye research to exploring brain health connections
• [16:23] Overcoming challenges in developing effective nutritional supplements
• [20:57] The role of preventative nutrition in eye and cognitive health
• [27:28] Key findings from major human trials on carotenoids and vision
• [33:37] Evidence linking carotenoids to cognitive health and aging
• [42:53] Practical insights for medical practitioners on using nutrition for eye health

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• Caretenoid supplement mentioned by Prof. Nolan: MacuPrime

In the world of sports nutrition, understanding how different supplements and nutrients impact not just physical performance but also cognitive function is rapidly gaining traction. Athletes are constantly seeking that competitive edge, and while many are familiar with the benefits of carbohydrates and caffeine for energy and focus, there’s much more at play.

Emerging research is highlighting the roles of compounds like creatine and omega-3s, not only for muscle recovery but also for brain health, particularly following traumatic brain injuries (TBI).

Beyond the usual suspects of performance nutrition, intriguing compounds like theacrine and tyrosine are entering the conversation. With potential cognitive effects that range from improved focus to faster decision-making, these supplements have sparked interest but also raise questions.

How strong is the evidence behind these claims, and where do we draw the line between scientific promise and practical application? How do we apply the science in real-world settings where perfect data may not exist?

This episode addresses these questions via the insights of Professor Shawn Arent of University of South Carolina.

• 01:44 – Dr. Arent’s key areas of research
• 04:03 – Defining and understanding cognitive performance in athletes
• 09:31 – The impact of carbohydrates on cognitive function and decision-making
• 29:00 – Protein, amino acids, and their role in cognitive function under stress
• 34:17 – How caffeine enhances cognitive performance: decision-making and reaction time
• 42:00 – Comparing the effects of theacrine and caffeine on cognitive and physical performance
• 44:48 – How caffeine dosing impacts sleep and recovery
• 46:55 – Theacrine, dynamine, and emerging supplements in sports performance
• 57:56 – Nicotine’s potential cognitive benefits and the associated risks for athletes
• 01:04:56 – Creatine and omega-3s: their roles in brain health and concussion recovery
• 01:13:05 – Navigating the challenges of applying research to real-world practice

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• Get research reviews from Dr. Eric Trexler and collegues

When discussing cardiovascular health, few topics stir as much debate as cholesterol, particularly in relation to low-carb and ketogenic diets. Recently, there’s been significant attention given to a proposed model that suggests high LDL cholesterol may not pose the same cardiovascular risk in certain individuals, specifically those labeled as “lean mass hyper-responders.” This raises important questions: Is it possible that high cholesterol might not be dangerous for everyone? Or are we witnessing a dangerous misinterpretation of the science?

In this episode, we break down the ideas behind the “lipid energy model” and explore how it has been framed in the context of low-carbohydrate and ketogenic diets. While proponents claim this model sheds light on how some people can have elevated LDL without increasing heart disease risk, critics warn that miscommunication and oversimplification of these ideas are leading many down a dangerous path. With real-world health decisions hanging in the balance, it’s crucial to carefully examine what the science truly says about cholesterol, inflammation, and heart disease.

Join us as we dive into the evidence with Dr. Gary McGowan. We’ll dissect what the current research supports, what remains speculative, and how social media has amplified both the promising and problematic aspects of this model. If you’ve ever wondered about the impact of high cholesterol on heart disease risk in the context of ketogenic or low-carb diets, this episode is essential listening.

• 02:27 What are the “Lean Mass Hyper Responder” phenotype and the “Lipid Energy Model”
• 27:29 Looking at recent publications and the “KETO Trial”
• 47:06 Public communication and misinterpretation
• 51:18 Clinical implications of diet-induced dyslipidemia
• 55:14 Responsibility in scientific communication
• 57:30 Real-world examples of poor communication or misinterpretation
• 01:13:27 Ethical concerns with the promotion of the model
• 01:25:59 Final thoughts

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• Find Dr. McGowan at:
  • Triage Method
  • Instagram: @drgarymcgowan
• Papers discussed in this episode:
  • Norwitz et al., 2022 – The Lipid Energy Model: Reimagining Lipoprotein Function in the Context of Carbohydrate-Restricted Diets
  • Norwitz et al., 2021 – Elevated LDL Cholesterol with a Carbohydrate-Restricted Diet: Evidence for a “Lean Mass Hyper-Responder” Phenotype
  • KETO Trial: Budoff et al., 2024 – Carbohydrate Restriction-Induced Elevations in LDL-Cholesterol and Atherosclerosis

Fasting has gained immense popularity as a dietary approach, but what does the scientific evidence say about its health benefits?

Studies have explored how fasting might influence metabolic markers, energy expenditure, and even aging. However, while fasting shows promise in some animal models, translating these effects to humans is less clear.

A key part of the debate centers on whether fasting offers unique health advantages or whether its benefits stem primarily from reduced calorie intake. Time-restricted eating and intermittent fasting protocols show promise in regulating appetite and reducing energy intake, potentially leading to weight loss. But, when calories are controlled, does fasting still improve health independently?

This episode explores the evidence to determine if fasting confers metabolic advantages over non-fasting diets. In addition, we’ll take a look at its impact on behavioral patterns and ask if that could play a pivotal role in promoting better health outcomes.

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Timestamps:

• [00:54] Defining fasting
• [03:44] Historical context and early research
• [08:01] Mechanisms and claims of fasting
• [18:15] Types of fasting protocols
• [22:18] Time-restricted eating and chronobiology
• [28:29] Energy expenditure and behavioral changes
• [36:53] Fasting vs. weight loss: independent benefits
• [41:47] Health markers and weight loss outcomes
• [43:37] Muscle mass concerns during fasting
• [47:31] Animal models vs. human studies
• [51:29] InterFAST study insights
• [01:00:37] Behavioral vs. metabolic changes
• [01:11:25] So what do we know?

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• Go to the page for this episode

Body image and self-worth are deeply intertwined concepts that influence how we see ourselves and interact with the world. Many people believe that changing their physique is the key to improving their body image, but is it really that simple? This connection between appearance and self-esteem raises important questions about how we define confidence and whether our sense of worth should be tied to how we look.

Our relationship with food plays a crucial role in how we view ourselves. While some see food as fuel, others attach much more significance to their eating habits, often linking dietary choices to discipline, success, or failure. But what happens when these beliefs become too rigid? Understanding how our perceptions of food and body image are shaped is essential for navigating the balance between health, happiness, and personal fulfillment.

Physique change, often seen as a positive goal, can bring about unexpected psychological impacts. Pursuing a leaner or more muscular body might boost temporary feelings of confidence, but could it also reinforce negative patterns of thought?

In an episode co-hosted with Dr. Eric Trexler, Danny talks with Dr. Gabrielle Fundaro in order to tackle some of these concepts and questions.

Timestamps:

• [04:54] Start of conversation
• [06:40] Defining body image and self esteem
• [12:26] Relationship with food and weight controllability beliefs
• [20:38] Impact of body composition on body image
• [27:40] Challenges in changing body image perceptions
• [34:43] Influence of coaches on client body image
• [41:57] Screening for disordered eating
• [51:50] Ethical responsibilities of fitness professionals
• [54:53] Improving body image without physique change
• [61:02] Key ideas segment (premium-only)

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• Get more of Dr. Trexler’s research analysis with the MASS Research Review
• Related previous episodes: See episodes 484 and 367

Some suggest that, since individual lifts or short-duration efforts don’t rely heavily on glycogen, carb intake might not be critical for strength athletes. If glycogen depletion isn’t a pressing issue, could athletes thrive on lower-carb diets without sacrificing performance? Or could there be overlooked benefits to having greater carbohydrate availablily in those sessions?

• In strength sports and resistance training, do carbohydrates play an important role or not?
• Are carbohydrates really necessary for resistance training?
• How does training volume, intensity and goals impact the carbohydrate requirement?

In this episode, Dr. Cliff Harvey and Dr. Eric Helms offer their perspectives on this interesting and practically important issue.

Timestamps:

• [00:03:40] Do carbohydrates have a role in resistance training?
• [00:12:23] Do individuals respond differently?
• [00:18:25] Recent research insights
• [00:35:08] Carbohydrate “sensing” and performance
• [00:47:17] How to think about carbohydrate needs
• [00:54:06] Changing views on nutrient timing
• [01:06:37] Ketogenic diets and muscle gain
• [01:22:02] Dietary patterns and health – Are macronutrients that important?
• [01:31:42] Key ideas segment (Premium-only)

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• Sports Nutrition Association
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• SigmaNutrition.com