Close

We use cookies to help improve your experience of our website and cookies have already been set. To find out more or for advice on removing these cookies, read our Privacy and Cookies Policy.

By closing this message or continuing to use our website, you consent to our use of cookies in accordance with our Cookies Policy.

Amino Acid Supplements

Amino Acids are the structural units that make up protein. Proteins are essential nutrients for the human body. They are the building blocks of the body and also serve as a fuel source. Amino acid supplements are increasing in popularity amongst athletes, bodybuilders and others on calorie-controlled diets.

All Amino Acid Supplements

SAVE
5%
Buy 5-HTP 100mg
5-HTP 100mg V
9.4 / 10
442 reviews
from £11.95
£11.35
  • Naturally sourced - 99% pure 5-HTP
  • Top selling supplement
  • Well researched nutrient
  • Good alternative to St John's Wort
SAVE
10%
Buy L-Arginine 1000mg
L-Arginine 1000mg V
9.4 / 10
204 reviews
from £10.95
£9.86
  • Very popular amongst sports people
  • Used by the body to make nitric oxide
  • Helps relax blood vessels
  • Acts as a powerful vasodilator
Buy L-Theanine 200mg
L-Theanine 200mg V
9.4 / 10
149 reviews
from
£12.95
  • Pure, strong and high grade material
  • Found predominantly in tea
  • Not known to be addictive
  • Fully vegetarian capsule
Buy Marine Collagen 400mg
Marine Collagen 400mg P
9.6 / 10
110 reviews
from
£10.95
  • The finest marine-sourced collagen
  • Contributes to skin elasticity
  • A guaranteed Amino Acid profile
  • Hydrolysed for easier absorption
Buy L-Lysine 500mg
L-Lysine 500mg V
9.6 / 10
40 reviews
from
£7.49
  • Cannot be made by the body
  • An essential amino acid
SAVE
50%
Buy L-Glutamine 500mg
L-Glutamine 500mg V
9.2 / 10
18 reviews
from £7.95
£3.98
  • Can assist tissue repair and growth
  • Easy to swallow capsule
  • A convenient amino acid source
Buy Branch Chain Amino Acid (BCAA)
BCAA 1000mg V
8.8 / 10
8 reviews
from
£10.95
  • Contains three key amino acids
  • In the important 2:1:1 ratio
  • Convenient tablet form
  • Contributes to growth in muscle mass
Buy L-Carnitine 500mg
L-Carnitine 500mg V
9.2 / 10
11 reviews
from
£10.95
  • High quality Amino Acid
  • Energy release
  • Bioavailable N-Acetyl form
  • A popular sports supplement
Buy L-Carnitine 1000mg
L-Carnitine 1000mg V
10.0 / 10
8 reviews
from
£9.95
  • High strength 1000mg tablet
  • A popular sports supplement
  • Aids in metabolising food into energy
  • Bioavailable N-Acetyl form
SAVE
10%
Buy High Strength L-Theanine 400mg
High Strength L-Theanine 400mg V
9.6 / 10
21 reviews
from £9.95
£8.96
  • Double-strength capsules
  • Purest form available
  • Strongest form available in the UK
  • Increases brain alpha waves

Not sure which Amino Acid Supplements to choose? Read our latest customer reviews:

The views expressed below are the personal opinion of Just Vitamins customers. Just Vitamins does not endorse these views, nor should they be regarded as health claims or medical advice. All reviews are collected and verified as genuine by a 3rd party called Feefo.

Product Name
Posted
Rating
Comment
5-HTP 100mg
18 Sep 2017
Service Rating: Very quick delivery and great packing
Product: Started to notice the effects in a week
High Strength L-Theanine 400mg
16 Sep 2017
Service Rating: Fast delivery, excellent packaging of product and delivery package (cardboard). The discount details were relayed to me quickly by support when I wrote to them. Regular updates on status of my order.
Product: Excellent and does what it says on the label. Keeps me calm and relaxed.
L-Theanine 200mg
09 Sep 2017
Service Rating: Excellent service, product arrived early and in perfect condition.
Product: I take these tablets now and then to improve mental focus and to help me to relax. It works very well, and seems to be a high quality product.
L-Arginine 1000mg
08 Sep 2017
Service Rating: Very good and fast delivery
Product: Very good and fast delivery
L-Arginine 1000mg
07 Sep 2017
good service- would buy from them again because of what they're selling!
L-Arginine 1000mg
07 Sep 2017
Good service.
Marine Collagen 400mg
07 Sep 2017
Service Rating: I m very happy with the transaction.
Product: Great product. I m very satisfy.
L-Arginine 1000mg
01 Sep 2017
Service Rating: Very good.
Product: Very good service. recommend this supplier.
5-HTP 100mg
31 Aug 2017
Service Rating: The postage was expensive
Product: The product was great and well packaged.
L-Theanine 200mg
30 Aug 2017
Service Rating: Quick delivery and reasonable prices.

I've been taking L-Theanine and a caffeine supplement for over 12 months now. Help me kick start the day and remain focussed without the caffeine jitters.

Also during times of anxiety L-Theanine and 5-HTP from this site have help members of my family through bereavement and other tough times.
Product: I've been taking L-Theanine and a caffeine supplement for over 12 months now. Help me kick start the day and remain focussed without the caffeine jitters.

Also during times of anxiety L-Theanine and 5-HTP from this site have help members of my family through bereavement and other tough times.
5-HTP 100mg
28 Aug 2017
Very happy with the supplements I ordered and I like the re-seal packs.
Marine Collagen 400mg
22 Aug 2017
Service Rating: good service fast reliable delivery, good choice of vitamins on offer
Product: I don't take them I order them for my girlfriend
L-Lysine 500mg
21 Aug 2017
Service Rating: I have been buying Coenzyme Q10 and Lysine from Just Vitamins for the last 5 years . Service and quality of goods never fails to be excellent.
Product: Good quality and easy to swallow.
5-HTP 100mg
20 Aug 2017
Service Rating: Arrived quick, sensible package for posting. Would definitely order again.
Product: Arrived quickly, sensible package, and a very good price. Very happy and will order again.
L-Arginine 1000mg
19 Aug 2017
Service Rating: everything went well
Product: Gives you a lot of energy.
L-Arginine 1000mg
19 Aug 2017
Service Rating: Quick delivery. Good product
Product: Quick delivery. Good product
High Strength L-Theanine 400mg
18 Aug 2017
Service Rating: I ordered L-Theanine from Just Vitamins which are recommended for helping to reduce the symptoms of stress. I found the website easy to navigate and the capsules arrived promptly. I feel the capsules are definitely helping and will be re-ordering when I need more. Thank you.
Product: I take one capsule daily and I personally feel an improvement in my stress levels. I will buy this product again.
L-Glutamine 500mg
16 Aug 2017
Service was excellent. Easy to order. Fab price and quick delivery.
Would highly recommend x
L-Arginine 1000mg
16 Aug 2017
Fast and efficient service
L-Arginine 1000mg
16 Aug 2017
Service Rating: szybka dostawa, dobrze zapakowany towar, ogólnie dobra informacja o produktach na stronie.
Product: nie daje skutków ubocznych, kapsułki niezbyt duże, dają się łatwo połykać, ogólnie samopoczucie mam dobre, ale za krótko używam, żeby konkretnie coś powiedzieć
We promise slick and speedy, same-day dispatch (Mon-Fri) on all orders received by 1pm!
Most of our products are delivered in super-slim pouches that slip neatly through your letterbox!

Free delivery throughout the UK

No minimum order needed - UK Standard delivery is free.

Sign-up for offers by email

Just Vitamins sends out monthly offers by email.
Payments by
PayPal, Google Checkout and all Major Credit/Debit Cards Accepted.
 
MHRA Approved
This site is protected by Trustwave's Trusted Commerce program
©2017 Just Vitamins Ltd,
Wolfe Road, Coventry, CV4 9UP, UK
UK Reg No. 3991727
Ecommerce By Zarr
Design By Amathias
Top