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#590: Is the Nutrient Density of Crops Declining? – Edward Joy, PhD

Sigma Nutrition Radio

Release Date: 01/13/2026

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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.

Timestamps

  • [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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