Berberine

Berberine is a plant-derived supplement that can strongly lower blood glucose, in part through the AMPK pathway; its effects were described as similar to metformin. It may also affect insulin and cholesterol, but it is a potent intervention—not a casual add-on. 1

• Main caution: Huberman described becoming hypoglycemic after taking it, with severe headaches and dizziness; taking it on an empty stomach or with low carbohydrate intake was singled out as especially risky. He recommends discussing it with a doctor and being particularly careful if you have blood-sugar problems. 2 3
• Evidence discussed: The episodes described studies suggesting lower blood glucose and HbA1c, and possible reductions in cholesterol and insulin. David Sinclair also noted human clinical trials reporting increased insulin sensitivity, while emphasizing that high doses had been used in those trials. 4 5
• Bottom line: The discussions stress caution and medical guidance; they do not establish a general-purpose dose or a reason for everyone to take berberine. 6