Episode Details

If nutrition can affect anxiety and depression, what should we actually measure, change, and investigate before reaching for another prescription?

Knowing that mental health can have nutritional and biological drivers is one thing. Knowing what to do with that information is another. Should we start with fiber, test vitamin D and iron, examine thyroid function, or investigate what is happening inside the cells? Without a clear approach, nutrition can easily become another world of guesswork, conflicting advice, and supposed quick fixes.

In Part 2, we move from understanding the nutrition, mental health connection to identifying the practical next steps. Dr. Oscar Coetzee explains why the average American may not be eating enough fiber to properly support the gut microbiome, which nutrient deficiencies he prioritizes when evaluating mental health symptoms, and how thyroid function can influence mood and energy. He also walks us through the organic acids test and what it can reveal about cellular energy, nutrient status, neurotransmitter pathways, stress, detoxification, and microbial activity.

In this episode, I continue my conversation with nutritionist, author, and speaker Dr. Oscar Coetzee. We explore how to investigate the biological factors affecting mental health without falling for quick fixes, why antidepressants should never be stopped abruptly, and the emerging probiotic research that Oscar believes could change how we support the gut and brain.

What You'll Discover in This Episode

• Why fiber matters for the gut bacteria involved in producing the building blocks for serotonin and dopamine

• How the average American's fiber intake compares with the amount Oscar believes is needed to improve the microbiome

• Why fiber should be increased gradually instead of added in large amounts overnight

• The connection Oscar sees between an underfed microbiome and rising levels of anxiety and depression

• Why vitamin D deficiency and iron deficiency are among the first problems Oscar investigates

• How anemia can affect mood, energy, and cognition, particularly in menstruating women

• Why B vitamins also deserve attention when evaluating mental health symptoms

• How selenium, iodine, and vitamin A support thyroid function—and why an underactive thyroid can resemble anxiety or depression

• The role omega-3 fatty acids and zinc play in supporting brain-derived neurotrophic factor

• How medication can provide short-term relief while nutritional deficiencies and other underlying problems are addressed

• Why Oscar is concerned about prescribing and combining multiple psychiatric medications in children and teenagers

• What an organic acids test can reveal that routine bloodwork may miss

• How this test can offer insight into mitochondrial function, B vitamin status, neurotransmitter pathways, cortisol, detoxification, and microbial activity

• Why mental health is too complex for Tik