Last updated: 17/10/2022

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Citrulline is an amino acid that converts to arginine in the body. Arginine is a precursor of nitric oxide, which causes vasodilation and increases blood flow to muscles during exercise. This helps improve athletic performance by increasing oxygen delivery to working muscles while reducing fatigue.

Citrulline: Bestsellers and current offers in the UK

The best citrulline in the UK: Our selection

Applied Nutrition’s L-Citrulline Supplements

Looking for a way to improve your cardiovascular health? Look no further than applied nutrition’s l-citrulline supplements. Each serving contains 1,500 mg of l-citrulline, an amino acid that plays an important role in boosting nitric oxide levels in the body. Nitric oxide is a molecule that helps keep arteries relaxed and blood flowing smoothly throughout the body. These capsules can also be helpful for people who are struggling with fatigue or endurance problems during workouts. The vegan-friendly, veggie shell makes this supplement the perfect choice for anyone with dietary restrictions.

Best Naturals L-Citrulline: 1500mg per 2 capsules, 90 count

Looking for a supplement to help support your protein metabolism and healthy immune system function? Look no further than Best Naturals L-Citrulline. Each 2 capsules contain 1500mg of l-citrulline, and there are 90 capsules per bottle. This product also promotes nitric oxide production and liver detoxification. It’s free of artificial colors, flavors, sweeteners, preservatives, sugars, starches, corn soy, eggs, lactose gluten wheat yeast fish sodium. Top quality GMP certified products – all Best Naturals products are manufactured in accordance with good manufacturing practices (GMP), among the highest standards in the world — proudly made in USA — purity & potency.

Need more energy? This high strength amino acid supplement is perfect for you.

Do you always feel tired? Feeling like you could do more if you only had the energy? Lack of motivation got you down? Our new high strength amino acid supplement is perfect for you. Made with pharmaceutical grade ingredients and manufactured in the UK under GMP, this pre-workout, muscle recovery and bodybuilding supplement will help to increase your energy levels, maintain normal testosterone and nitric oxide levels (important for protein synthesis and blood flow) and give you the extra boost you need to get through your day. It comes in a minimalist, slimline packaging which slips directly through your letterbox – no waiting in or visits to the post office required.

Citrulline Malate 2:1 – For Improved Pumps & Performance

Looking for a pre-workout that will give you an edge? Look no further than our 100% pure citrulline malate. In a 2:1 ratio, this formula is designed to increase nitric oxide production for improved pumps and supports energy levels. Citrulline malate is also beneficial to muscular endurance, making it perfect for athletes or anyone looking to improve their performance. Plus, we offer free delivery on all UK orders.

Citrulline: Frequently asked questions

What types of Citrulline are there and what determines a good product?

There are three types of Citrulline. L-Citrulline, which is the most common form found in supplements and food products; D-Citrulline, a rarer type that has been shown to be more effective at increasing Nitric Oxide levels than L-Citrulline; and Citrillic Acid (also known as 1-(2H)-Pyrrolidinone), an intermediate compound formed during the conversion from one amino acid to another.

Citrulline is a non-essential amino acid, which means that the body can produce it on its own. It’s also found in food sources like watermelons and bananas. The best citrulline supplements are made from L-citrulline malate or L-arginie nitrate (ARG). These two forms of citrulline have been shown to be effective for improving blood flow during exercise, as well as increasing muscle growth and recovery after workouts.

Who should use a Citrulline?

Anyone who wants to increase their performance in the gym or on the field. Citrulline is a great supplement for anyone looking to get more out of their workouts and training sessions, whether you are an athlete or just someone trying to stay fit.

Based on what criteria should you buy a Citrulline?

You should buy a Citrulline that has been proven to be effective. The best way of determining this is by looking at the ingredients list and seeing if it contains L-Citrulline Malate or Nitrosigine, which are two forms of citrulline that have been clinically tested for effectiveness in improving muscle pumps during exercise. If you want more information on how to choose between these two types of supplements then check out our guide here .

Citrulline is a non-essential amino acid, which means that your body can produce it on its own. However, if you are not getting enough of this nutrient in your diet or through supplementation then the chances for muscle fatigue and soreness increase significantly. A good supplement should contain at least 3 grams per serving to be effective.

What are the advantages and disadvantages of a Citrulline?


Citrulline is a non-essential amino acid that can be converted into arginine in the body. Arginine has been shown to increase nitric oxide levels, which improves blood flow and oxygen delivery to muscles during exercise. This leads to better muscle pumps and increased endurance for athletes who rely on anaerobic energy systems (like weightlifters). It also helps with recovery by reducing soreness after workouts.


There are no disadvantages associated with a Citrulline.

What should I keep in mind when taking Citrulline? Any special precautions?

If you have been diagnosed with kidney disease, it is recommended that you do not take this supplement as your kidneys may be more sensitive to the effects of citrulline. If you experience any side effects from using this product, discontinue use and contact your doctor immediately.

Shopping Guide: Everything you need to know

Which brands and manufacturers are represented in our review?

In our review, we present products from various manufacturers and suppliers. The list includes products from the following brands and manufacturers, among others:

  • Best Naturals
  • Applied Nutrition
  • Best Naturals

What is the price range of the featured products?

The cheapest Citrulline in our review costs around 10 pounds and is ideal for customers who are conscious about their money. However, those who are willing to spend more money for better quality can also spend around 34 pounds for one of the more expensive products.