UNTAPPED with Spencer Matthews UNTAPPED with Spencer Matthews

3 Deficiencies Holding You Back | Extra Mile

Oct 8, 2026 · 42m

Summary

Host Olly Patrick and guest Bella discuss common nutritional deficiencies, focusing on iron, vitamin D, and B12. They explain how these nutrients impact blood production, oxygen transport, and bone health, highlighting specific risks for runners and women. The episode covers the difference between heme and non-heme iron, the role of sunlight in vitamin D synthesis, and the importance of B12 for red blood cell formation. They advise using blood tests to diagnose issues rather than relying on symptoms alone and emphasize that correcting deficiencies is more beneficial than excessive supplemen…

Topics discussed

Introduction and episode overview Identifying iron deficiency and the fatigue myth Blood tests, absorption issues, and GP consultation Heme vs non-heme iron and dietary sources Ferritin, vitamin C, and absorption disorders Iron strategies for vegan and vegetarian diets The role of supplements and risks of excess iron Iron needs and the menstrual cycle Vitamin D: functions, sunlight, and hormone status Vitamin D supplementation and bone density Measuring vitamin D and athletic injury risk Skin pigmentation, sunlight, and dietary sources Vitamin B12 and its role in blood production B12 in vegan diets and injection treatments Altitude, EPO, and the danger of excess nutrients Sponsor segment: Amex Gold Card Interpreting blood test ranges and personal baselines Long-term supplementation and lifestyle integration Inflammation, training, and accurate blood testing Symptoms of iron deficiency beyond fatigue Symptoms of vitamin D and B12 deficiencies Dietary optimization vs. processed food trends Conclusion: prioritizing diet over supplements Closing remarks and sign-off
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