How unhealthy are processed foods?

It’s a common assumption that processed foods are unhealthy and a cause of overweight and obesity. And it is sometimes true: Processed foods can, for instance, contain four times more calories than unprocessed foods.

Processed foods can be any kind of food that has been altered in production.

That can be food that’s had vitamins or coloring added, or food that’s been made safe for human consumption, such as pasteurized milk.

Strictly speaking, a freshly-baked loaf of organic whole grain bread is processed, because the individual ingredients have been altered in the baking process. But we still tend to say that “processed foods” are bad for us, when in fact it depends on the extent to which the foods have been processed.

The results of a new study aim to show why processed foods and even ultra-processed foods aren’t unhealthy per se — but that they are far more likely to contain more calories and lack nutrients and vitamins.

Processed foods: more calories on average

Published in the British Journal of Nutrition, the study found that ultra-processed foods in the UK contained more food energy than mildly processed foods.

On average, ultra-processed foods contained four times more calories than minimally processed foods — the ultra-processed foods contained on average 378 calories per 100g compared to 94 calories per 100g of minimally processed food.

Not all ultra-processed foods in the study contained high amounts of energy, however. A number of the products had similar nutritional values as mildly processed foods.