This episode focuses on the intersection of nutrition, lifestyle, and women’s health, with a particular emphasis on managing complex conditions such as PCOS, endometriosis, and premenstrual dysphoric disorder (PMDD).

Registered dietitian Marjorie Nolan Cohn shares insights from over two decades of clinical practice, highlighting the importance of addressing foundational health behaviors—such as adequate sleep, hydration, and nutrient-dense dietary patterns—before introducing targeted interventions like supplementation.

Marjorie explores the nuanced relationship between body weight, metabolic health, and fertility, while addressing misconceptions around weight loss as a primary health goal. The episode examines the role of long-term, individualized care in improving symptoms and outcomes for women experiencing significant menstrual-related challenges.

Practical considerations for practitioners, including strategies to build trust, identify key barriers, and provide holistic support, are outlined alongside the importance of interdisciplinary collaboration to improve care quality.

Marjorie Nolan Cohn is a registered dietitian with a Masters Degree in Food and Nutrition Science from the Indiana University of Pennsylvania. She is the Clinical Director of Berry Street, a company providing virtual in-network nutritional counseling to people across the US.

• [04:32] Beginning of the interview
• [08:39] The role of nutrition in fertility
• [13:40] Understanding PCOS and endometriosis
• [16:28] Barriers to accurate women’s health diagnoses
• [19:03] Exploring diet and lifestyle strategies
• [23:28] Addressing challenges in women’s health and nutrition
• [39:01] Closing remarks and final takeaways

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• Guest website: Berry Street

Over the past couple of decades, renowned researcher Dr. Marie-Pierre St-Onge has uncovered fascinating links between how we sleep and what we eat, revealing how these two lifestyle factors influence energy balance, cardiovascular health, and metabolic function.

In this episode we’ll explore Dr. St-Onge’s findings on sleep regularity and its association with reduced mortality risk, providing actionable insights for optimizing your lifestyle. With a focus on combining rigorous methodologies and controlled dietary interventions, her research sheds light on the complex mechanisms connecting sleep, diet, and metabolic health.

Timestamps:

• [03:39] Dr. St-onge's academic journey and evolution of her research interests
• [07:03] Overcoming methodological challenges in sleep and nutrition research
• [10:20] The importance of sleep regularity for health
• [15:44] Exploring the bidirectional connection between diet and sleep
• [23:40] Unpacking the mechanisms linking diet to sleep quality
• [37:33] Practical recommendations for optimizing sleep and diet

Links:

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• Article: How Sleep & Nutrition Interact – Alan Flanagan, PhD
• Go to episode page

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