One capsule. 90 minutes. A 53% rise in the molecule that determines your skin's brightness from within. Here's the minute-by-minute biology — explained like you're actually a human being, not a biochemist.
There is one number that sits at the heart of everything Continual-G is built on: 53%. As in, 53% increase in intracellular glutathione — the glutathione inside your skin and blood cells — in 90 minutes from a single oral dose of Glyteine®. This number comes from a 2017 clinical study published in a peer-reviewed scientific journal called Redox Biology. The researchers were Zarka and Bridge (PMID: 28131081, if you want to look it up). And what they found changed how anyone paying attention thinks about glutathione supplementation.
But before we get into the study, let's actually understand what's happening inside the cell — because the magic of this number is in the biology, and the biology is genuinely fascinating once it's explained the right way.
The Continual-G capsule hits your stomach. Unlike a glutathione tablet — which gets torn apart by your digestive enzymes almost immediately — Glyteine® (γ-glutamylcysteine) is structurally different. It's a smaller molecule, a dipeptide (two amino acids linked together, not three), and it's absorbed in a way that lets enough of it survive to reach your cells. Think of it like a smaller package that fits through the postal slot when the big one gets left at the door.
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Here's where Glyteine® does what glutathione itself cannot. Your cells have specific protein transporters in their membranes — like keyed locks that only certain molecules can open. Glutathione doesn't have a key for most cell types. Glyteine® does. It's the exact molecule your cell uses in step one of its own internal glutathione production — so the cell has a transport mechanism built for it. Glyteine® is absorbed from the gut, enters the bloodstream, reaches your cells, and slips inside through the transporter.
Once Glyteine® is inside the cell, something elegant happens. The cell already has an enzyme waiting — called glutathione synthetase. This enzyme's entire job is to take γ-glutamylcysteine (Glyteine®) and add a third amino acid (glycine) to complete the glutathione molecule. Your cell doesn't have to struggle. It doesn't have to fight through its rate-limiting step (the GCL enzyme — more on this in Blog 06). It has the direct precursor and the enzyme ready to go. The cell builds glutathione. From within. In the location where it needs to be.
In the Zarka & Bridge study, participants had their blood drawn at multiple time points. The researchers measured intracellular glutathione — not plasma glutathione floating around in the blood, but the glutathione inside the cells. At 90 minutes, the rise was 53% above each individual's own baseline. Not 5%. Not 15%. Fifty-three percent. And crucially — above homeostasis. Homeostasis is the cell's natural setpoint, the level it tries to maintain. A 53% rise above homeostasis means the cell's antioxidant machinery is operating significantly above its usual ceiling.
Most glutathione studies measure plasma glutathione — the glutathione in your blood. This is the easy measurement. It's accessible, it fluctuates with supplementation, and it makes for impressive-looking graphs. But plasma glutathione is the bus outside your house, not the furniture inside your house. The antioxidant activity that controls melanin production, neutralises free radicals in your skin cells, and actually produces the glow you can see — all of that happens intracellularly. The Zarka & Bridge study measured the right thing. That's what makes it different.
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The Zarka & Bridge study is a pilot study — meaning it had a smaller participant group than a large randomised controlled trial. Larger confirmatory studies would strengthen the evidence base further. We say this clearly on the Continual-G listing on SkinBB, in the LabelLooker™ breakdown, and in Ingredipedia. The mechanism is well-supported by established biochemistry. The intracellular evidence is stronger than anything published for standard oral glutathione. And the published data is the honest foundation for every claim we make. No inflated promises. No hiding the asterisks.
In 90 minutes, a single capsule of Continual-G with Glyteine® raises intracellular glutathione by 53% above baseline — inside the cells, where the glow actually comes from. The cell absorbs Glyteine®, builds its own glutathione through its own machinery, and the result is a measurable rise in the molecule that controls melanin, neutralises free radicals, and powers the antioxidant network. No equivalent published data exists for standard oral glutathione. 90 minutes. 53%. That's the proof. The rest is just packaging.
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1. Can I read the actual study?
Yes. Zarka MH, Bridge WJ. Oral administration of γ-glutamylcysteine increases intracellular glutathione levels above homeostasis in a randomised human trial pilot study. Redox Biology, 2017. PMID: 28131081. Search PubMed. SkinBB links directly to it on the Continual-G product page.
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2. Does the 53% rise happen every time I take a capsule?
Each dose triggers a fresh intracellular synthesis cycle. With daily use, your glutathione level is consistently supported above its natural setpoint. The acute 53% peak is from a single dose study; daily use maintains the antioxidant advantage rather than letting it cycle back to baseline.
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3. Do I feel anything in 90 minutes?
Probably not — intracellular changes aren't felt, they're accumulated. You won't feel a glow in 90 minutes. But your cells are responding from day one. Visible skin changes typically appear over 8–12 weeks of daily use.
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