GSH is produced within the cells (intra-cellularly). When it is taken orally, it has not been shown in clinical studies to be absorbed in the blood stream but is broken down during digestion and eliminated. Taking food that is rich in GSH also results in non-absorption and very little effect in raising GSH level in the body. The most effective and natural way that has been proven scientifically to raise intra-cellular GSH is by giving our cells precursors (building blocks) to manufacture GSH. The 3 bioactive proteins or bonded-cysteine in Immunocal® constitute a natural ‘delivery system’ from the cystine precursors to the cells.

These cystine precursors are easily transported inside the cell whereby they can be quickly converted to cysteine upon cell entry and synthesized into GSH. The availability of cysteine determines how much GSH we can synthesize. However, cysteine as a dietary supplement can promote hypercysteinemia and potential toxicity hence, is not recommended.