Malcolm Clark, policy manager at Cancer Research UK, said: "Even before its formal introduction the levy has already had a significant effect, encouraging numerous biggest companies to go further and faster in changing their recipes to reduce the sugar in their drinks".
Those with 8g per 100ml will face a tax rate of 24p per litre.
Coca-Cola chose not to reformulate Coca-Cola Classic, the UK's most popular branded soft drink, and prices are expected to increase as a result.
Shortly after the 2016 announcement, Lucozade Ribena Suntory launched Lucozade Zero in the United Kingdom, citing "the nation's changing health agenda". Some companies have replaced sugar with artificial sweeteners and have avoided the tax.
Past year the recipe of Dr Pepper was changed and the drink contains 32% less sugar than before. Now many drinks contain less sugar, presumably in order to not be hit so hard by the tax. The drinks most affected are of the fizzy kind such as Pepsi, Red Bull, 7Up and Coca-Cola.
"Research shows how negatively sugar affects the liver for instance, and the knock-on effects of too much sugar are known to raise risks of obesity, type 2 diabetes and many other health problems that have become so common". Half of Britons said they would cut down on unhealthy foods and drinks if they were more expensive, according to a study from Mintel.
Unhappy about the sugar tax? But will ramping up the cost of high-sugar drinks put fizz in the fight against childhood obesity, or will it fall flat?
There are nine teaspoons of sugar in a 330ml can of cola, which instantly takes children above their recommended maximum sugar intake for the day. The same goes for any that have more than 8g of sugar per 100ml.
"Customer experience is more important than ever, so aim to offer innovative soft drinks, lower in sugar but perfectly served, to stand out from the crowd". Similarly, he mentioned that the government would consider implementing a similar tax on candies and chocolate, if they felt it was a necessary step towards encouraging healthier recipes.