How to decode a food label

The ingredients are listed from the main ingredient to the least ingredient by weight. For hazelnut spread, the first (and biggest) ingredient is sugar, then oil.

• Lower down, you'll come across "E numbers". The EU uses these shortcodes to describe additives. For example, E300 is vitamin C, E160c is paprika.
• In the US, there is no such coding. Instead, additives are described by their chemical names, such as sodium caseinate rather than E469. But it really refers to a protein derived from milk.

Some nations like the UK use red, amber, and green colour codes to express how healthy a processed food is in terms of fat, saturates, sugars and salt. 

For example, a processed meal might have 7.7g of saturated fat and be labelled red. It may also show a percentage like 39%. The amount is calculated using the "Reference intake", which is the maximum recommended intake amount for an adult woman who does an average amount of physical activity.

Serving size was another definition that may seem obvious at first but is complex to define. Until the Nutrition Facts label appeared, each manufacturer decided for themselves how big a portion was.

• The 1990 US legislation mandated that the serving size should be the amount "customarily consumed and which is expressed in a common household measure that is appropriate to the food"—but knowing what a serving size is required national surveys. 
• In the end, the FDA calculated the US serving sizes by using 139 categories, which includes four types of cereal and four types of cheese.

Health claims are regulated to avoid manufacturers over-promising. 

The US uses three relevant types of claims:

• Authorised claim: The approved claim must have "significant scientific agreement."
• Qualified claim: The science is not settled. "Scientific evidence suggests..."
• Structure-function claim: These claims are vague, such as "calcium builds strong bones". They should be viewed as marketing language.