Maintaining the ability to carry out everyday tasks and live independently is often described as a cornerstone of healthy ageing. But what actually happens to muscle strength, power, and functional ability as we get older? And how inevitable is their decline?

At what point do changes in muscle function really begin to matter for day-to-day life? Is loss of strength an unavoidable consequence of ageing itself, or does it reflect something more modifiable? If declines are not fixed, what kinds of training or lifestyle interventions genuinely make a difference, and how strong is the evidence behind them?

In this episode, exercise physiologist Dr Brendan Egan examines these questions through the lens of both epidemiological data and controlled training studies in older adults. What do we learn from short-term resistance training interventions lasting just a few months? Do the gains persist once supervised training ends? And what does this tell us about the practical challenges of maintaining functional capacity over the long term?

The conversation also explores the idea of "use it or lose it" in muscle function, the role of resistance training in extending healthspan, and how exercise programmes can be designed to support independence later in life. Ultimately, the episode asks a simple but crucial question: what does the evidence actually say about staying strong, capable, and functionally independent as we age?

Dr. Brendan Egan is an Associate Professor of Sport and Exercise Physiology the School of Health and Human Performance at Dublin City University. Currently, he is Associate Dean for Research in the Faculty of Science and Health.

• [03:49] Understanding functional capacity
• [05:56] The importance of muscle strength and mass
• [14:09] Epidemiology and strength training
• [25:07] Concurrent training in older adults study
• [31:05] Barriers to strength training in older adults
• [34:18] Misconceptions about older adults and exercise
• [39:13] Exercise snacking and SBAE
• [51:04] Key ideas segment (Premium-only)

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Nutrient density refers to the concentration of vitamins and minerals in crops relative to their yield. There are widespread claims that today's fruits, vegetables, and grains contain fewer micronutrients than in decades past, often linked to modern farming practices or soil degradation.

This issue is important because if staple crops become less nutritious, it could silently undermine dietary quality and contribute to micronutrient deficiencies ("hidden hunger") in populations.

Dr. Edward Joy is uniquely qualified to address this topic. As a senior research fellow in food systems and nutrition at Rothamsted Research and an associate professor at the London School of Hygiene & Tropical Medicine, his work centers on the intersection of agriculture and nutrition.

In this conversation, Dr. Joy draws on evidence from agronomy and public health to clarify whether the nutrient content of crops has indeed declined, what factors might be responsible (from soil health to plant breeding and climate change), and what we can do to improve the situation.

The discussion emphasizes an evidence-based perspective on soil nutrients, crop varieties, and interventions, cutting through myths to identify real concerns and practical solutions.

• [00:55] Interview
• [04:49] Understanding nutrient density and soil health
• [10:25] Historical evidence and crop experiments
• [20:39] Impact of climate change on crop nutrition
• [24:05] Potential solutions and future research
• [30:34] Translating research to human health

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• Rothamsted Research
• Dr. Joy's profile page
• X/Twitter:
  • @edward_joy1
  • @NutritionDanny

This is a Premium-exclusive episode of the podcast. To listen to the full episode you need to be subscribed to Sigma Nutrition Premium.

Recently we (Danny Lennon & Alan Flanagan) were invited to 'Processing the Evidence', a "behind closed doors" workshop to discuss the latest scientific evidence on the role of processed foods in human health. The event was organized by Professors Ciarán Forde and Vincenzo Fogliano of Wageningen University in the Netherlands.

The workshop attendees included a range of prominent researchers across a range of domains related to food processing, nutrition science, and public health. The sessions included open discussions on current evidence, knowledge gaps and challenges within the UPF debate.

There were several structured sessions looking at different sub-topics, such as:

• • Emulsifier-gut interactions
  • Ultra-processing and its effect on food matrix and bioavailability
  • Food liking and hedonic overeating
  • UPFs: Interpreting nutritional epidemiology and RCTs
  • New trial data: the PROMENADE trial, the RESTRUCTURE Trial, etc.

In this episode, Alan and Danny review some of the key talking points and their takeaways from this event.

• • [00:31] Event overview: processing the evidence
  • [04:44] Conference insights with Dr. Alan Flanagan
  • [07:52] Hypotheses on ultra processed foods
  • [11:53] Microbiome and additives panel
  • [21:51] Food science and technology panel
  • [33:21] Behavioral aspects of food consumption
  • [38:10] Nutritional epidemiology session
  • [47:19] Discussion on dietary pattern classification
  • [50:19] The role of ultra-processed foods in public health policy
  • [54:18] Clinical and metabolic data on processed foods
  • [01:00:55] Critique of the NOVA classification system
  • [01:08:03] Concluding thoughts on ultra-processed foods
  • [01:23:12] Key ideas and methodological standpoints

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