Elemental Selenium and Vitamin B2 (riboflavin) are essential for glutathione use and recycling. Selenium is really low in Australian soils, and people are commonly deficient. Signs of low B2 are blood The Krebs cycle is the central engine of cellular energy metabolism. It's where your body gets most of its energy from food. If you are low in any of these B vitamins, Frontiers Riboflavin in neurological diseases: therapeutic advances, metabolic insights, and emerging genetic strategies 10.4: Riboflavin Medicine LibreTexts Simplifying the B Complex: How Vitamins B6 and B9 Modulate One Carbon Metabolism in Cancer and Beyond Glutathione: Master Antioxidant, Reducing Oxidative Stress, and Detoxification