Denmark has become the first country in the world to impose a "fat tax" on unhealthy foods.
The move will place a surcharge on foods high in saturated fat. Butter, milk, cheese, pizza, meat, oil and processed food will all be subject to the levy.
The aim is to reduce people's intake of fatty foods. But consumers have begun hoarding provisions ahead of the price rise and some scientists have suggested that it would be better to target people's salt or sugar intake.
The Nordic country introduced the tax Saturday, of 16 kroner (£1.85) per kilogram of saturated fat in a product.
The tax was approved by large majority in a parliament in March as a move to help increase the average life expectancy of Danes.
In September, Hungary introduced a new tax popularly known as the "Hamburger Law," but that only involves higher taxes on soft drinks, pastries, salty snacks and food flavorings.
The outgoing conservative Danish government planned the fat tax as part of a goal to increase the average life expectancy of Danes, currently below the OECD average at 79 years, by three years over the next 10 years.
"Higher fees on sugar, fat and tobacco is an important step on the way toward a higher average life expectancy in Denmark," health minister Jakob Axel Nielsen said when he introduced the idea in 2009, because "saturated fats can cause cardiovascular disease and cancer."
Linnet Juul says the tax mechanism is very complex, involving tax rates on the percentage of fat used in making a product rather than the percentage that is in the end-product.
Linnet Juul's organization is pressuring lawmakers to simplify the tax, but said he is unsure what will happen when the new, centre-left government takes office. AP