Stop the green-tea and fish-oil regimen, and the mitochondrial gains faded within three months — in children with Down syndrome

Edited by Samael A. Tejada, Founder & Editor-in-Chief

Most supplement studies end at the last dose. This one kept measuring after the last dose — and watched the improvement unwind.

What was the regimen, and what had it done before?

The children — eight in all, aged 6 to 17, recruited at Federico II University Hospital, Naples — had taken a decaffeinated green-tea extract providing EGCG at 10 mg/kg/day (maximum 480 mg/day) mixed with an omega-3 formulation providing 250 or 500 mg/day of EPA+DHA, for at least six months. The group's earlier clinical study reported that six months of the combination was safe and restored mitochondrial complex I and ATP synthase activities in peripheral blood mononuclear cells (PBMCs).

What happened during the three months off?

Discontinuation produced a progressive loss of the bioenergetic benefits across repeated sampling (baseline, then 30, 45, 60 and 90 days). The proportion of depolarized mitochondria carried in large circulating extracellular vesicles (lEVs) increased by three months. Whole-blood transcriptomics showed downregulation of pathways for oxidative phosphorylation, mitophagy, autophagy and lysosomal function, and plasma metabolomics showed remodelling of lipid and fatty-acid metabolism — a pattern the authors read as impaired mitochondrial and redox homeostasis returning.

What are the limits — and the useful signal?

The numbers are tiny and uneven: respiratory-chain activities in all eight children, but vesicle analyses in four and matched omics in as few as three, because paediatric blood volumes limited sampling. There was no parallel group that kept taking the supplements, so reversal is inferred from the within-child trajectory. Even so, two signals are worth noting: the durability question matters for any family weighing a daily regimen, and the vesicle finding — that the polarization state of mitochondria riding in blood-borne vesicles tracked the change — is a candidate non-invasive readout of mitochondrial homeostasis worth testing properly.

Where the evidence stands

• Established: Down syndrome involves chronic oxidative stress and mitochondrial dysfunction, and this group's earlier work reported that EGCG plus omega-3 improved respiratory-chain activities in these children's blood cells.
• Preliminary: The withdrawal effect and the vesicle readout: one small pilot study (Antioxidants, 2026), n=8 with some analyses in 3-4 children, no continuing-treatment control group.
• Absent: Evidence on clinical outcomes — cognition, health, or daily function — from either taking or stopping this regimen, and any dosing guidance for families.