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Pure Encapsulations L-Glutamine 850 mg is a free-form amino acid supplement providing glutamine - the most abundant amino acid in the body and a primary fuel source for the cells lining the gut wall.
£30
Pure Encapsulations L-Glutamine 850 mg is a free-form amino acid supplement providing glutamine - the most abundant amino acid in the body and a primary fuel source for the cells lining the gut wall.
Pure Encapsulations L-Glutamine 850 mg is a free-form amino acid supplement providing glutamine - the most abundant amino acid in the body and a primary fuel source for the cells lining the gut wall. Glutamine is conditionally essential, meaning demand can outstrip the body's ability to produce it during periods of physiological stress, intense training, illness, or following gut disruption.
Follow the dosage on the packaging. The existing guidance suggests 1–2 capsules daily; many practitioners advise taking glutamine away from large meals or first thing in the morning on an empty stomach, but consult your clinician if unsure about your specific protocol.
It is most commonly used to support intestinal barrier integrity, particularly by those with increased gut permeability, digestive complaints, or who are recovering from a course of antibiotics or a period of poor dietary intake. Athletes in heavy training blocks also reach for glutamine, as prolonged exercise is associated with a measurable drop in circulating levels.
Immune cells - especially lymphocytes and macrophages - rely on glutamine as a key substrate, so supplementing during periods of high demand may help maintain normal immune function alongside adequate dietary protein.
Pure Encapsulations is a brand with a longstanding commitment to clean formulation: minimal excipients, no unnecessary fillers, and a straightforward label. This SKU provides 850 mg of free-form L-glutamine per capsule, allowing flexible dosing. It suits those who want a simple, single-ingredient supplement without proprietary blends or added compounds. As with any amino acid supplement, results are most meaningful when dietary protein intake is otherwise adequate.
Standard UK delivery included on every order, 1 to 3 working days after dispatch.
Next working day for £25 when you order by 12pm. Orders placed before 12pm on a working day leave the same day. Later orders leave the next working day.
You can return unopened and unused items within 30 days of delivery. This does not affect your statutory rights. Read the delivery and returns terms
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Sign inThose most likely to benefit include people with gut permeability concerns, individuals in high-volume athletic training, anyone recovering from illness or antibiotic use, and those whose diet is temporarily low in dietary protein. Glutamine is conditionally essential, meaning demand rises significantly under physiological stress.
Yes, L-glutamine is compatible with protein supplements — it is itself an amino acid. Some practitioners prefer it taken on an empty stomach to maximise absorption by gut epithelial cells, but taking it with a light meal is also reasonable. Check with your clinician if you have a specific therapeutic goal.
For gut-related goals, some people notice a gradual improvement in digestive comfort over several weeks of consistent use, particularly when combined with dietary changes. For immune or recovery support, effects are more subtle and best assessed alongside other markers. There is no universal timeline.
High-dose amino acid supplementation is generally approached cautiously in those with significant kidney or liver impairment, as these organs are involved in amino acid metabolism. If you have a known condition affecting either, speak to your GP or specialist before starting.
Dietary sources such as meat, fish, eggs, and dairy do provide glutamine, but the free-form supplement allows a targeted, measurable dose without additional macronutrients. This matters when dosing is being used therapeutically — for example, to support gut repair — rather than purely for general nutrition.
Overall
6 months ago
Had a rough couple of months after a long course of antibiotics left my digestion all over the place. Started taking these about three weeks in and noticed a real difference within a fortnight — less bloating, more regular. Nothing dramatic, just a steady improvement. Clean ingredients, no weird fillers, which was exactly what I was looking for.
6 months ago
I'm midway through a heavy block of marathon prep and started adding glutamine after reading about how endurance training depletes it. Hard to say whether it's this specifically or everything together, but my gut has felt more settled on long runs. Would buy again.
6 months ago
Exactly what it says on the tin. Single ingredient, clean capsule, flexible dosing. I take two before bed alongside my magnesium. Gut feels better than it has in a while.
7 months ago
Quality seems spot on and I do feel like my digestion has improved after about a month. My only gripe is the capsule size — they're on the larger end and I do find them a bit awkward to swallow if I'm taking a few at once. If you don't mind that, they're worth it.
7 months ago
I work in healthcare and noticed my digestion always suffers when I'm run down or on nights. A colleague suggested glutamine and I've been on this brand for about six weeks now. Gut is calmer, fewer flare-ups of that horrible post-shift bloating. Good stuff.
8 months ago
Been using this for two months now. Swapped from a cheaper powder form and honestly prefer the capsules — easier to fit into a routine. Noticeable improvement in how my stomach handles high-volume training weeks.
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