The sugar tax comes into effect today.
People will be paying 30 cent per litre more for drinks that are high in sugar, as part of a bid to tackle Ireland's obesity crisis.
It is thought the tax will generate up to €40m euro in the first year.
Professor Donal O'Shea, the HSE's Lead for Obesity says it is an important day.
He said: "The sugar tax is going to increase the cost, that will reduce consumption, we know that is what tax does.
"It is the single initiative that is most likely to impact on childhood overweight and obesity that the Government can act on.
"If it is done properly and evaluated then Ireland can show the rest of the world that this really does work."
Food Drink Ireland is coming out against the introduction of the sugar tax.
Director Paul Kelly says most soft drinks will not be taxed anyway.
He said: "We think the measure is very much a system measure rather than a health measure.
"It is going to cost consumers money out of their pocket and the reality is over three quarters of soft drinks now aren't going to be covered by the tax.
"The main reason they won't be covered by the tax is that industry has been taking sugar out of the products for many years well in advance of this tax taking place."
- Digital Desk