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 VV
9.4 / 10
475 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 VV
9.4 / 10
221 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 VV
9.4 / 10
156 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
119 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 VV
9.6 / 10
46 reviews
from
£7.49
  • Cannot be made by the body
  • An essential amino acid
SAVE
10%
Buy High Strength L-Theanine 400mg
High Strength L-Theanine 400mg VV
9.6 / 10
36 reviews
from £9.95
£8.96
  • Double-strength capsules
  • Purest form available
  • Strongest form available in the UK
  • Increases brain alpha waves
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

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
L-Arginine 1000mg
19 Apr 2018
Service Rating: Very quick service, convenient in postal delivery
Product: Feeling more energetic, using it to increase energy throughout the day.
5-HTP 100mg
18 Apr 2018
Service Rating: I have purchased a product which was in great price, through easy website and which was delivered quickly and for a fraction of the cost other retailers charge. Fantastic service :-) Thank you.
Product: I am not sure how to recommend it yet, because I have just started supplementation a couple of weeks ago. I can see some positive changes, but it's too early to fully exhaust pros and cons.
5-HTP 100mg
17 Apr 2018
Excellent service and products really good quality.
5-HTP 100mg
15 Apr 2018
Fast delivery and nice products
L-Arginine 1000mg
11 Apr 2018
Service Rating: I didn't receive my package and didn't get a refund either
Product: I didn't receive it and the company didn't issue a refund either
Feedback Response: Thank you for your feedback.

We're sorry to hear you haven't received your order.  As promised your goods were sent out to you the day after you placed your order. Our Customer Services team will contact you directly to resolve this issue with you.
L-Lysine 500mg
10 Apr 2018
Service Rating: Easy ordering,fast delivery nothing more needed
Product: Useful,tackles skin problems caused by being run down
5-HTP 100mg
09 Apr 2018
Service Rating: Always fill orders accurately. Quick delivery. Reasonably priced.
Product: Easy to take and I feel much less emotional.
High Strength L-Theanine 400mg
09 Apr 2018
Service Rating: VERY GOOD FAST SERVICE
Product: GOOD SERVICE, QUICK DELIVERY
L-Theanine 200mg
08 Apr 2018
Service Rating: quick delivery, effective service
Product: Help me with study, or could be placebo.
Still, I rate them.
High Strength L-Theanine 400mg
08 Apr 2018
Very good
L-Arginine 1000mg
08 Apr 2018
Excellent service and quality!!
5-HTP 100mg
07 Apr 2018
Great range of products at a good price. The vitamins arrived on time in letter box friendly packages. Recommend and will re-order for sure.
High Strength L-Theanine 400mg
07 Apr 2018
Service Rating: Just ordered one type of product, which was very good.Overall experience was pleasant and delivery was very fast.
Product: Did not try similliar products from competition but it does what it's supposed to with a very good price!
Marine Collagen 400mg
06 Apr 2018
Service Rating: quick delivery and a wide range of products available
Product: It is easy to take as it comes in capsules and I am taking them for recommendation
5-HTP 100mg
06 Apr 2018
Service Rating: great service, great product, will definitely use just vitamins in future
Product: these are great value, am rather pleased to have found just vitamins!
L-Theanine 200mg
06 Apr 2018
Service Rating: Great service. Smooth and easy.
Product: Struggle with anxiety on a daily basis. This helps to some extent. Calms my body down and relieves stress.
High Strength L-Theanine 400mg
06 Apr 2018
Service Rating: Great Products, prompt delivery, thanks!
Product: Great Quality, affordable prices, nice packaging
High Strength L-Theanine 400mg
06 Apr 2018
Good service
Wish you had thenine in smaller portions
5-HTP 100mg
06 Apr 2018
Fast efficient service, would definitely buy again.
High Strength L-Theanine 400mg
04 Apr 2018
Service Rating: Product has yet to arrive and its been 3 likes, will update review if it arrives.

Product arrived later than expected but due to a 3rd party postal service, so no complaints about Just Vitamins service.
Product: Cant review as not arrived
Feedback Response: Thank you for your feedback.We dispatch all orders (including yours) on the next working day of receipt, but unfortunately we are at the mercy of the local postal service once it leaves us.  Our customer services team will be contacting you.
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
©2018 Just Vitamins Ltd,
Wolfe Road, Coventry, CV4 9UP, UK
UK Reg No. 3991727
Ecommerce By Zarr
Design By Amathias
Top