Multivitamin and multimineral supplements have long been a topic of both scientific inquiry and public debate. While they are often marketed as convenient solutions for achieving nutritional adequacy, their true value remains contentious.

Are these supplements essential insurance policies against nutrient deficiencies, or are they merely expensive placebos?

Importantly, how should we weigh their potential benefits against the lack of robust evidence for long-term health outcomes such as reduced mortality or chronic disease risk? These questions demand a nuanced exploration, grounded in the context of specific populations and individual needs.

Ultimately, the role of multivitamin supplements cannot be assessed in isolation but must be viewed through the lens of context and specificity. How do we balance the biological plausibility of benefits against the variability of individual diets, the presence of fortification policies, and the challenges of achieving dietary adequacy in certain life stages?

These considerations invite a more thoughtful and less binary discussion about whether, when, and for whom multivitamins are a worthwhile addition to the diet.

• [00:22] The debate on multivitamins: worthless or beneficial?
• [00:53] Rationale behind multivitamin use
• [04:04] Modern nutritional adequacy and multivitamins
• [07:10] Evidence supporting multivitamin use
• [23:39] Long-term health outcomes and multivitamins
• [41:43] Cognitive outcomes
• [50:18] Pregnancy and multivitamin use

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• Shaun Ward Article: Multivitamin Madness: There’s More to Life than Death
• Studies mentioned:
  • MacPherson et al., 2013 meta-analysis of randomized controlled trials
  • Jenkins et al., 2021 meta-analysis
  • COSMOS trial – Vyas et al., 2024 analysis of three substudies
  • Loftfield et al., 2024 – Multivitamin Use and Mortality in 3 Cohorts
  • Blumberg et al., 2017 nutritional adequacy paper

While the fitness industry often emphasizes short-term goals such as rapid weight loss or aesthetic improvements, a growing body of evidence highlights the importance of fostering long-term habits for health and wellbeing. Understanding how psychological frameworks intersect with physical health behaviors is key to empowering clients and overcoming the challenges posed by rigid dieting practices or the influence of social media culture.

Bodybuilding and fitness culture serve as both a microcosm and an extreme example of the challenges faced in this space. As the boundaries between physique sports and general fitness blur, many enthusiasts adopt unsustainable habits without fully understanding their long-term implications. How can fitness professionals effectively guide clients toward intrinsic motivations and healthier relationships with food and exercise while balancing the reality of external pressures?

In this episode, Laurin Conlin offers her insights based on her coaching experiences, as well as formal training in exercise sciences and mental health counselling. Dr. Eric Trexler co-hosts the episode with Danny Lennon.

• [05:41] Challenges in dieting and coaching practices
• [09:58] Bridging physical and mental health through coaching practices
• [13:15] Recognizing and navigating disordered eating behaviors in fitness clients.
• [22:01] The physiological and psychological challenges in physique sports.
• [34:52] Fitness culture and social media influence
• [37:19] Misunderstanding intuitive eating
• [41:23] Using motivational interviewing and reflective listening to guide clients
• [52:13] Integrating mental health practices in fitness and nutrition coaching
• [62:13] Key Ideas segment (Premium-only)

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• Sports Nutrition Association
• Get research reviews from Dr. Eric Trexler and collegues

Eating disorders and disordered eating behaviors represent complex, multifaceted challenges that affect individuals across all demographics, yet they remain widely misunderstood and under-recognized. These issues often extend beyond the stereotypical images associated with eating disorders, touching everything from rigid “clean eating” obsessions to the normalized extremes of diet culture.

At the heart of these behaviors lies a disruption in one’s relationship with food, often fueled by societal pressures, unrealistic body ideals, and a pervasive focus on aesthetics over health. While these challenges are tenacious, recovery and improved relationships with food are possible with the right interventions, resources, and awareness.

In this episode, Danny talks to Dr. Jillian Lampert, a registered dietitian with a PhD in public health nutrition, with a speciality in eating disorders and disordered eating.

• [02:56] – What are eating disorders? a breakdown of core concepts
• [05:15] – Beyond stereotypes: the widespread impact of eating disorders
• [14:41] – Disordered eating in sports and fitness: risks and realities
• [19:41] – Guidance for practitioners: recognizing and addressing red flags
• [22:50] – Barriers in treating eating disorders: challenges and solutions
• [43:50] – Advocacy and systemic change: the future of eating disorder care

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• The Emily Program
• Eating Disorders Coalition for Research, Policy, & Action (EDC)
• National Alliance for Eating Disorders

In a world flooded with information, discerning fact from fiction in fitness and nutrition has never been more challenging—or more important. The rise of social media and democratized science has given everyone a platform, but not all voices are equal.

How do we navigate a landscape where influencers with massive followings wield the same credibility as seasoned experts? Why do pseudoscientific trends gain traction while nuanced evidence gets lost in the noise?

In this episode we also dive into the evolution of coaching, examining how the obsession with quantifiable metrics has shifted the focus away from human connection. How can professionals balance the drive for scalable success with the need for meaningful client relationships? And what lessons can we draw from decades of shifts in the fitness industry to stay resilient amid rapid societal and technological changes?

• [04:33] Eric’s personal journey and influence
• [06:08] Evolution of bodybuilding coaching
• [10:32] Challenges in interpreting scientific research
• [17:35] Historical trends in diet and nutrition
• [25:49] Information overload and misinformation
• [43:07] Understanding fractional counting in hypertrophy
• [44:24] Challenges in communicating scientific concepts
• [47:27] The psychology of persuasion
• [49:07] The role of marketing in science communication
• [54:46] Balancing data and intuition in coaching
• [01:03:59] Navigating the future of nutrition coaching
• [01:08:34] Building trust and connection with clients

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• Dr. Helms’ MASS Research Review is a monthly publication that includes easy-to-read breakdowns of the latest training and nutrition research

IGF-1 (Insulin-Like Growth Factor 1) has emerged as a hot topic in health and nutrition discussions, often linked to longevity, cancer risk, and metabolic health.

On one hand, IGF-1 is essential for growth, repair, and metabolic regulation; on the other, it is sometimes associated with disease processes, including cancer and cognitive decline.

For those intrigued by the intersection of nutrition, biomarkers, and disease prevention, IGF-1 offers an opportunity to explore how science grapples with these complexities.

Claims about manipulating IGF-1 through dietary changes — whether by reducing protein or adopting fasting protocols — are common. But does the evidence support these claims?

If you’re curious about IGF-1 and the relationships between diet, disease, and healthy aging, in this Premium-exclusive episode Danny and Alan discuss this fascinating topic.

To listen to the full episode, subscribe to Sigma Nutrition Premium

• [02:21] IGF-1 and Diet: Examining the Relationship
• [09:15] IGF-1 as a Biomarker: Challenges with Sensitivity and Specificity
• [11:54] IGF-1 and Cancer Risk: Insights and Complexities
• [25:51] IGF-1 in Aging: Cognitive Function and Longevity Considerations
• [43:38] Key Takeaways: IGF-1, Diet, and Practical Advice

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• Murphy et al., 2020 – observational and Mendelian randomization analyses

Fitness pursuits can bring various benefits. However, within the modern fitness industry there is a complex interplay of body image ideals, societal pressures, and disordered eating behaviors.

Research continues to illuminate how certain practices and messaging within the industry—such as the overvaluation of leanness or the impact of social media personas—can fuel body dissatisfaction and disordered eating.

For fitness coaches and enthusiasts alike, this raises important questions:

• What defines success in fitness?
• How can individuals engage in training and nutrition without falling into harmful traps?
• And how can professionals align their practices with values that support long-term well-being for themselves and their clients?

In this episode, Michelle Carroll, a PhD researcher in clinical psychology, explores these questions in depth. Drawing on her academic work and personal experiences, she discusses the implications of fitness industry norms, the challenges of online coaching, and practical steps for fostering healthier relationships with food and body image.

• [01:15] Defining disordered eating and body image
• [03:47] Motivations behind this research
• [05:37] Impact of the fitness industry on body image
• [08:29] Challenges and misconceptions about body image
• [14:26] Physical capital and pressures on fitness professionals
• [18:20] Consequences of harmful fitness industry messaging
• [35:04] Positive changes and gaps for future research
• [40:16] Practical advice for professionals and individuals

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• Michelle’s website
• Michelle on Instagram: @michellecarroll1
• Disordered Eating Informed – Course

Healthspan, healthy ageing, and chronic disease are pivotal topics in today’s health discourse, emphasizing not just the length of life but the quality of those additional years. Focusing on healthspan means striving for a longer period of life free from disease and disability, which is increasingly important as global life expectancies rise. Healthy ageing involves adopting lifestyle habits that promote physical, mental, and social well-being throughout the lifespan, thereby reducing the risk of chronic diseases such as heart disease, diabetes, and neurodegenerative disorders.

Addressing chronic diseases risk requires a proactive approach centered on prevention and early intervention. By prioritizing healthspan and healthy ageing, individuals can significantly decrease the likelihood of developing chronic illnesses, leading to improved quality of life and reduced healthcare costs.

Sigma Nutrition Radio has consistently addressed these critical themes across many episodes. In this episode, we go back over some of the best episodes of 2024 in this area, including discussions on Alzheimer’s, cholesterol-lowering medications, impact of exercise, and the debate about red meat.

• (03.12) Alzheimer’s: Genetic susceptibility vs. modifiable factors
• (14.59) Heart disease: the “risk factor, disease, event” framework
• (22.10) The strength of evidence we have for the impact of exercise on mortality and longevity
• (28.23) Why high blood pressure is so problematic
• (37.23) Where do we see risk for unprocessed red meat?
• (48.34) The evolution over the years of dietary fat research
• (53.20) Claims about the proposed risks of consuming seed oils
• (56.16) How does fat quality impact heart disease risk?
• (60.35) History of Portfolio Diet research for reducing LDL-C

• 512: Alzheimer’s Disease – Drs. Ayesha & Dean Sherzai
• 525: Cholesterol-Lowering Medication – Dr. Paddy Barrett
• 524: Strength & Fitness Levels for Reducing Chronic Disease Risk & Promoting Health Ageing – Jordan Feigenbaum, MD
• 527: How to Prevent & Treat Hypertension – Dr. Mohammed Alo, DO
• 528: Is Unprocessed Red Meat Problematic for Our Health?
• 532: Dietary Fat: Evidence vs. Misinformation – Alice Lichtenstein, DSc
• 515: Does Dietary Fat Quality Causally Affect Atherosclerosis Risk? – Jacob Christensen, PhD
• 507: Does a Higher Portfolio Diet Score Reduce Heart Disease? – Andrea Glenn, PhD

Links:

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• Go to episode page

Navigating the complex and often underemphasized requirements of professional standards, legal considerations, and insurance can be challenging for sports nutrition practitioners and personal trainers.

Many professionals, especially early in their careers, may overlook or minimize these responsibilities, focusing primarily on the practical and enjoyable aspects of helping clients achieve their goals. However, staying informed and adhering to these standards is not only essential for providing ethical, competent service but is also crucial for minimizing liability.

Ignoring or misinterpreting scope-of-practice guidelines and insurance limitations can leave well-meaning professionals exposed to significant legal and financial risks that could have lasting consequences on their careers.

In this episode, Alex Thomas joins Danny Lennon and Eric Helms to discuss the essential, if often overlooked, responsibilities that define a successful and resilient career in sports nutrition.

Together, they explore best practices for insurance, scope of practice, and the importance of aligning with professional organizations that provide educational and legal support.

• [01:57] The SNA Introduction
• [03:31] The importance of professional standards
• [09:58] Legal consequences and real-world examples
• [15:23] Insurance and scope of practice
• [23:27] Navigating the gray areas in nutrition practice
• [30:51] Legal risks in nutrition advice
• [34:50] Ethical dilemmas and referral networks
• [36:53] Emerging trends and risks in nutrition services
• [48:49] Becoming a competent sports nutrition professional

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• Sports Nutrition Association

Carbohydrate metabolism and metabolic health have become central themes in the science of nutrition, with questions about fuel utilization, the impact of different diets, and the potential of ketone supplements driving new research.

As researchers continue to uncover how the body adapts to various energy sources, there are emerging insights into how glucose tolerance, glycogen utilization, and even ketogenic diets influence not only physical performance but also long-term health outcomes.

Understanding how the body responds to different energy sources, particularly in relation to carbohydrate restriction, brings crucial context to popular nutrition strategies and the potential benefits—or trade-offs—they offer.

In this episode, Professor Javier Gonzalez joins to discuss these topics in detail, exploring the latest findings on how dietary choices affect athletic performance, chronic disease risk, and the mechanisms underlying metabolic adaptations.

You will gain insight into topics like reactive hypoglycemia, carbohydrate oxidation, and why individualized responses to diet matter.

• [01:36] Understanding carbohydrate metabolism
• [06:33] The role of glucose in metabolic health
• [09:59] Exercise and glucose dynamics
• [17:35] Carbohydrate intake and athletic performance
• [25:03] Diet impact on exercise and metabolism
• [30:44] Pre-workout carbohydrates and reactive hypoglycemia
• [35:31] Recent study: Ketogenic diet vs. sugar restriction
• [41:09] Future research directions in metabolic health
• [45:07] Ketone esters and their role in exercise performance
• [49:22] Carbohydrate metabolism and common misconceptions

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• Paper: Ketogenic diet but not free-sugar restriction alters glucose tolerance, lipid metabolism, peripheral tissue phenotype, and gut microbiome: RCT 

Appetite and satiety are fundamental concepts shaping how we eat, why we feel hunger, and what keeps us satisfied after meals. From the biological signals sent by our gut to the psychological influences of food cues, understanding these processes can provide valuable insights into how we manage our food intake.

In this episode, we delve into the interplay between hormones, food properties, and external factors that regulate appetite and fullness, exploring how these mechanisms work together—or sometimes fail—in modern eating environments.

We will examine fascinating topics such as the satiety cascade, sensory-specific satiety, and the impact of nutrient composition on hunger regulation. This episode also highlights how individual differences, such as satiety phenotypes, shape eating behavior, offering a nuanced perspective on the science of satiety.

Whether you’re interested in applying these concepts to your diet or supporting others in managing hunger, this discussion offers practical takeaways grounded in scientific evidence.

To listen to the full episode, subscribe to Sigma Nutrition Premium.

• [02:22] Understanding appetite and satiety
• [07:28] Biological mechanisms behind hunger regulation
• [10:57] Sensory and psychological cues affecting food intake
• [26:54] Nutrient composition and its influence on satiety
• [43:11] Practical strategies for managing hunger

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