A Cape Town Review Surveys Rooibos Compounds Against Alzheimer's Damage

A review by South African scientists has surveyed how compounds from the red bush act on the cell-level damage found in Alzheimer's disease, and judged the case worth a clinical trial. The review, by Elias Chipofya, Taskeen F. Docrat, and Jeanine L. Marnewick of the Cape Peninsula University of Technology, appeared in Molecular Nutrition and Food Research.

The work is preclinical. It catalogues pathways rooibos compounds have been reported to act on in laboratory and animal studies, among them oxidative stress, tau protein, amyloid plaques, inflammation, and the role of metals, and finds no human trial of rooibos against the disease.

Behind the review sits a working laboratory. Docrat, a researcher at the Cape Peninsula University of Technology, is studying how rooibos extracts interact with amyloid beta, the protein that clumps into plaques in the brains of people with the disease, and with mitochondrial dysfunction, the failure of the structures that supply a cell with energy. Her work compares fermented (red) and unfermented (green) rooibos, and tracks markers of oxidative stress and the small regulatory molecules called microRNA.

The research is supported by the South African Rooibos Council in collaboration with the Department of Science and Innovation's Sector Innovation Fund. "Although we are still busy with these studies, preliminary findings look promising, suggesting that Rooibos could positively impact these factors," Docrat said. She said the work is laying the foundation for findings that would guide future human clinical trials.

What none of this is, is a finding that drinking rooibos prevents or treats dementia. The work sits at the cell and laboratory level, backed by a review of other laboratory and animal studies, with no clinical trial in people. "Promising in the laboratory, and worth a clinical trial" is where the science stands, well short of anything to do at the kettle.

So the standing line holds, as it always does on health. Rooibos is caffeine-free and rich in antioxidants, among them aspalathin, and that is the whole of the claim. It does not cure or detoxify anything, and a hopeful early study does not change that.

Sources: E. Chipofya, T. F. Docrat, and J. L. Marnewick, "The Neuroprotective Effect of Rooibos Herbal Tea Against Alzheimer's Disease: A Review," Molecular Nutrition and Food Research, vol. 69, no. 1 (2025), published online Dec. 19, 2024; Women in Science Africa, "Scientists Explore Rooibos' Potential against Alzheimer's Disease"; Klipopmekaar, "Scientists Explore Rooibos' Potential To Protect Against Alzheimer's Disease." All framing reflects that this is preclinical research, not clinical proof.