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WeightWorldAmino acids & derivatives

L-Theanine Capsules

£15.49 for 180 servings at WeightWorld. It carries more than one active ingredient, so it is not ranked against single-ingredient products. Each price below counts one ingredient only.

What it really costs, per 200 mg4pOne 200 mg dose is our comparison unit for L-Theanine. It is not a recommendation.
A day4p
A week30p
A month£1.29
A year£15.71

At one 200 mg dose a day, this pack lasts 12 months. A month is 30 days, so twelve of them is not quite a year.

How we worked it out

L-Theanine

  • In the pack: 180 × 400 mg = 72 g
  • £15.49 ÷ 72 g × 200 mg = 4.3p per 200 mg
  • A week 4.3p × 7 = 30p · a month × 30 = £1.29 · a year × 365 = £15.71
  • Amount per serving: stated on the label.

Black pepper (piperine)

  • In the pack: 180 × 1 mg = 180 mg
  • £15.49 ÷ 180 mg × 5 mg = 43p per 5 mg
  • A week 43p × 7 = £3.01 · a month × 30 = £12.91 · a year × 365 = £157.05
  • Amount per serving: active constituent content stated on the label (or its stated percentage of the extract).

Vitamin B6

  • In the pack: 180 × 0.5 mg = 90 mg
  • £15.49 ÷ 90 mg × 50 mg = £8.61 per 50 mg
  • A week £8.61 × 7 = £60.24 · a month × 30 = £258.17 · a year × 365 = £3141.03
  • Amount per serving: stated on the label.

The standard dose is a comparison unit, not a recommendation. Always confirm the price on the retailer's site. How we compare everything.

How it compares: L-theanine

All 12, ranked →
L-TheanineCheapest per 200 mgHealf · 200 mg a serving · £4.12 a month · a pack lasts 4 months14p£16.49View at Healf (opens in a new tab)
L-TheanineHealf · 250 mg a serving · £5.60 a month · a pack lasts 2 months19p£13.99View at Healf (opens in a new tab)
L-TheanineW-Wellness · 250 mg a serving · £6.20 a month · a pack lasts 2 months21p£15.49View at W-Wellness (opens in a new tab)
WeightWorldThis productWeightWorld · 400 mg a serving · £1.29 a month · a pack lasts 12 months4pshown above

Ranked purely by price per 200 mg. 70 combination products also contain L-Theanine.

How it compares: black pepper extract

All 4, ranked →
Ayurvediq WellnessOrganic Ashwaganda & Black Pepper ExtractCheapest per 5 mgVitamin Planet · 10 mg a serving · £2.51 a month · a pack lasts 8 months8p£20.04View at Vitamin Planet (opens in a new tab)
Turmeric & BioPerine® CapsulesMyprotein · 10 mg a serving · £2.58 a month · a pack lasts 6 months9p£15.49View at Myprotein (opens in a new tab)
Turmeric & BioPerine® CapsulesMyprotein · 10 mg a serving · £2.75 a month · a pack lasts 2 months9p£5.49View at Myprotein (opens in a new tab)
WeightWorldThis productWeightWorld · 1 mg a serving · £12.91 a month · a pack lasts 36 days43pshown above

Ranked purely by price per 5 mg. Labels here do not all state the same thing: this one gives active constituent content stated on the label (or its stated percentage of the extract), the cheapest gives extract weight stated on the label. Check both before choosing. 75 combination products also contain black pepper (piperine).

How it compares: vitamin B6 pyridoxine HCl

All 6, ranked →
ZipVitVitamin B6 50mgCheapest per 50 mgZipVit · 50 mg a serving · £1.00 a month · a pack lasts 12 months3p£11.99View at ZipVit (opens in a new tab)
Vitamin B6 Tablets 50mgSimply Supplements · 50 mg a serving · £1.11 a month · a pack lasts 12 months4p£13.29View at Simply Supplements (opens in a new tab)
Vitamin B6 100mgHealf · 100 mg a serving · £1.39 a month · a pack lasts 7 months5p£9.25View at Healf (opens in a new tab)
WeightWorldThis productWeightWorld · 0.5 mg a serving · £258.17 a month · a pack lasts 2 days£8.61shown above

Ranked purely by price per 50 mg. 280 combination products also contain vitamin B6.

On the label

L-Theanine · L-theanine
400 mg per serving (stated on the label)
Black pepper (piperine) · Black pepper extract (piperine)
1 mg per serving (active constituent content stated on the label (or its stated percentage of the extract))
Pack
180 servings · 1 capsule(s) a serving
Cost per serving
9p (180 servings in the pack)
More label details
Vitamin B6 · Pyridoxine HCl
0.5 mg per serving (stated on the label)
Sold by
WeightWorld
What the listing says
“Servings per Container: 180” · “Serving Size: 1 Capsule” · “Black Pepper Extract (98% Piperine) ; 1.05 mg” · “Providing Piperine ; 1 mg”
Ingredients

Bulking Agent: Microcrystalline Cellulose, Anti-Caking Agent: Hydroxypropyl Methylcellulose, Vege Capsule Shell: Hypromellose (HPMC) Advice Do not exceed the recommended daily dose. Food supplements must not be used as a substitute for a varied and balanced diet and a healthy lifestyle. Discontinue use if any adverse reactions occur. Not intended for use by persons under the age of 18.

From the WeightWorld listing. Check the pack itself if you have an allergy: labels mark allergens in bold.

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One 200 mg dose is our comparison unit, not a recommendation.

Price history

No price change since 9 October 2026. Checked on 1 day, most recently 9 October 2026.

Price at every check
£15.49WeightWorld
First recorded
£15.499 Oct
Checked on
1 daysince 9 Oct

Checked once so far, on 9 October 2026.

  1. First checked at WeightWorld: £15.49

Questions about this product

How much does WeightWorld L-Theanine Capsules cost per 5 mg?

43p per 5 mg, from £15.49 for 180 servings at WeightWorld, checked on 9 October 2026.

How long does one pack last?

36 days at one 5 mg dose. The pack holds 180 mg in total.

How much does WeightWorld L-Theanine Capsules cost per 200 mg?

4p per 200 mg, from £15.49 for 180 servings at WeightWorld, checked on 9 October 2026.

How long does one pack last?

12 months at one 200 mg dose. The pack holds 72 g in total.

How much does WeightWorld L-Theanine Capsules cost per 50 mg?

£8.61 per 50 mg, from £15.49 for 180 servings at WeightWorld, checked on 9 October 2026.

How long does one pack last?

2 days at one 50 mg dose. The pack holds 90 mg in total.

About WeightWorld

All 124 WeightWorld products, priced per dose

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