It seeks to ensure that consumers know what they put in their mouths. Any food packaging designed after March 1 will reflect the new Department of Health regulations.
The law, first announced in 2010 and commonly referred to as R146, regulates the labelling and advertising of foodstuffs in an effort to curb unsubstantiated claims.
The Act stipulates that a description of the ingredients contained in the food must be printed clearly next to the product name, and it must not be misleading; nutritional claims like "high in fibre", "sugar free" and "low fat" must be accompanied by a nutritional table to substantiate the claims and there should be a quantitative ingredient declaration that breaks down the amount of ingredients that are advertised on the product label.
Allergens must also be declared.
Guy Kebble from SurePure said: "Currently, the food labels do not reflect the things that are in the food and how food is prepared. If a supermarket sells you fruit juice they will call it 'fresh'. How fresh is it if it was boiled to prolong its shelf life.
"Consumers need to know what happens between the tree and the supermarket counter.
"We are unaware of the preservatives that are in our food. How can fruit juice be fresh if it is cooked?"
He said during the production process preservatives are introduced to food.
Kebble said that the law will benefit people with allergies.
"The people will see exactly what is in their food and what would make them sick."
He said it would take a while to roll out the regulations but: "People need to be scared so they can evaluate what they eat. If consumers are scared by what is in their food, they will demand that the producers make healthier food for them. We still have a long way to go because the Act has no implications on the wine industry, for instance.
"They are only supposed to write in small print that their wine contains sulphur and not how much."
Other than the nutritional value of products disclosure of the country of origin on imported foodstuffs is now compulsory.