Gym regulars Optimum Nutrition creatine's 643g tub is under £30, and is one of Amazon's top sellers

Creatine is everywhere right now. Hardly a week goes by without a new study on what the powder can do for your muscles, you brain and your ageing joints.

Just this week claims have been made by Harvard Health, that the sports supplement may even help build muscle without having to exercise.

Bold claims of course, and for many gym-goers it doesn’t matter, because creatine is the go-to for helping achieve successful gains after a tough workout.

If you've been thinking about trying out creatine, Amazon's Big Deal Days has knocked down the very popular Optimum Nutrition.

The big 634g tub of Micronised Creatine Monohydrate is £27.99, down from Amazon's £40 list price and has been one of the biggest sellers of day one of Prime Big Deal Days.

SHOP NOW: The Optimum Nutrition creatine deals

• Micronised Creatine Monohydrate, 634g: £27.99, down from £40 This is the best value per serving.
• Micronised Creatine Monohydrate, 317g: £9.89, down from £15.99
• Platinum Creatine Plus, 50 servings: £20.89, down from £24.70

Optimum Nutrition Creatine is on offer in Amazon Prime Big Deal Days

Who should take creatine?

Nutritionist Bethan Crouse told The Guardian there was 'really substantial evidence of creatine being effective' and that there's been plenty of research into the impact the supplement can have.

However, she warned that it's not for everyone, and not even for everyone who is really into their exercise.

She said: "I think saying ‘everybody should take creatine’ is a jump too far at this stage. If you’re serious about your sport, or you’ve already got the basics of your nutrition nailed and you’re looking to improve performance, then it’s definitely worth considering. But for the general population, it’s not a necessity."

The nutritionist explained that many of the benefits of creatine could be provided through a healthier diet anyway, chowing down on oily fish such as salmon or mackerel and scoffing flaxseed and chia seeds for better nutrition.

It makes most sense if you train regularly and already have the basics of your diet sorted. That applies whether you lift, run or do classes.

How much creatine should you take?

An adult dose of 3 to 5 grams of creatine daily is generally safe for most people, according to Harvard, though those with kidney disease should consult their doctor first.

More isn't better, so there's no need to load up. If you have kidney problems, are pregnant or are breastfeeding, speak to your GP before you start.

What is creatine?

Creatine is produced from amino acids in organs such as the kidneys, liver, and pancreas.

It is primarily stored in the muscles to provide rapid energy during high-intensity exercise, meaning it is the ideal pre-workout supplement for those looking to push themselves to the max.

It has been proven that most creatine comes from a balanced diet, as it can be found in protein-heavy food such as meat and dairy products, but an additional amount can help people go the extra mile.