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Amazon Prime Day has delivered some serious savings across beauty and wellness, but one deal that's sure to put a smile on shoppers' faces is 40 per cent off MySweetSmile Teeth Whitening Powder.

An Amazon bestseller for three years in a row, the powder has recently undergone a makeover of its own, thanks to a new 3-in-1 formula that whitens teeth while helping to support enamel and protect gums. If you’ve suffered from yellowing teeth for years, you might have given up trying to improve them, but this powder has been clinically proven to deliver results. And you can add it to your cart for under £20. 

MySweetSmile Teeth Whitening Powder – 6 Month Supply 

MySweetSmile holds more verified Trustpilot reviews than any other whitening brand in the UK with over 8,000 real customer testimonials and an "Excellent" rating on Trustpilot.

Now 40 per cent off for Prime Day, MySweetSmile's new 3-in-1 formula does more than simply whiten teeth.

Designed to tackle deep-set staining while supporting enamel and protecting gums, the bestselling powder has earned more than 8,000 reviews and has been Amazon UK's number-one teeth whitener for three consecutive years.

£17.99 (save £7) Shop

The new and improved 3-in-1 formula sees the biggest Amazon discount ever with a huge 40 per cent off

Independent clinical testing carried out under dental supervision confirmed measurable improvements in tooth colour after four weeks of daily use of the MySweetSmile whitening powder. 

Using standardised colour measurement methods to objectively track results, dental specialists verified that the powder produced clinically measurable whitening results rather than subjective changes based on perception alone.

And better yet? Unlike sodium peroxide or charcoal-based tooth whitening formulas, which can damage tooth enamel, MySweetSmile's new 3-in-1 formula is designed to be gentle on teeth.

As well as helping to remove years of staining from coffee, tea and red wine, the teeth whitening powder contains Hydroxyapatite to support enamel and Vitamin E to protect gums, making it particularly appealing to those concerned about sensitivity or ageing teeth.

At the same time, it’s tough on stains, with the key ingredients Calcium Carbonate to remove plaque and other debris as you brush, and natural enzymes derived from pineapple and papaya to dissolve stains that other products can’t reach.

Each pot lasts for six months, with the 40 per cent off Prime Day discount making it the equivalent of just 14p a day.

And according to over 8,000 shoppers, the results are jaw-dropping, from the first use. One impressed shopper posted before and after photos following the first try, explaining: ‘This result is from one use (4 minutes of powder followed by my normal brush, floss and mouthwash).

Prime member can now shop the teeth whitening powder for just £17.99 for 6 months (that's 35p per use)

‘I'm so impressed and can't wait to see how it goes. Photos are taken in the same room under the same lighting, there is no additional brightness or change of light/effects. 

Another compared the MySweetSmile Teeth Whitening Powder favourably to professional treatments, writing: ‘Well this stuff produced better results after one application that the dental hygienist has ever done and now after 3x usage my teeth look more like they did when I was 30, not 60!’

Available in tasty strawberry and mint flavours, MySweetSmile could be the simple addition to your daily routine that helps you feel more confident showing off your smile this summer.

The Prime Day deal comes at the perfect time of year for socialising, when calendars start filling up with holidays, weddings, barbecues and family get-togethers, and a brighter smile should make you feel more confident in photos.

But with the 40 per cent saving ending on 26 June, if you’re tempted to give your smile a summer refresh, you may want to add it to your basket sooner rather than later.