The studies both tied consumption of “ultra-processed foods with risk of cardiovascular disease and death”, said the BMJ.
In the first study, researchers from the University of Paris monitored 105,159 people for five years looking for associations between intake of ultra-processed food and overall risk of cardiovascular, coronary heart, and cerebrovascular diseases.
The participants’ diets were assessed twice a year using the NOVA classification system, which groups foods into four categories according to the extent and purpose of industrial processing involved.
The ultra-processed foods category is defined by NOVA as “formulations of food substances often modified by chemical processes and then assembled into ready-to-consume hyper-palatable food and drink products using flavours, colours, emulsifiers and . . . other cosmetic additives”.
These foods include savoury snacks, reconstituted meat products, pre-prepared frozen dishes, and soft drinks.
Participants were also asked to report major health events. After taking account of factors such as age, BMI, smoking status, alcohol consumption and physical activity, the study discovered a there was a 12% increase in the risk of cardiovascular disease for every 10% increase in the amount of ultra-processed food consumed.
Put another way, there were 242 cases of cardiovascular disease per 100,000 people per year, rising to 277 among those eating the most ultra-processed food. There were also higher incident rates of
There was also an increased risk of coronary heart (124 vs 109) and cerebrovascular diseases (163 cases vs 144).
In the second study, researchers from the University of Navarra in Spain, monitored 19,899 people from 1999 to 2014 and assessed their diet every other year, also using NOVA. There were 335 deaths over the course of the study. After factors such as age, sex, body mass index and smoking were taken into account, participants who were eating more than four servings of ultra-processed food a day were 62% more likely to have died than those eating the least ultra-processed food. For each additional serving of ultra-processed foods, risk of death increased by 18%.
“These findings add to growing evidence of an association between ultra-processed food and adverse health outcomes that has important implications for dietary advice and food policies,” said the BMJ. “The dietary advice is relatively straightforward: eat less ultra-processed food and more unprocessed or minimally processed food.”
Policy makers should ‘shift their priorities away from food reformulation’
The findings also have implications for policy actions such as front of pack labelling, food taxation, and restrictions on food marketing, said the BMJ, which require an evidence informed metric to determine the “healthiness” of individual food products.
“Currently, decisions about individual products are based on either dietary recommendations or nutrient profiling “scores,” both of which have limitations for this purpose,” the BMJ noted.
The BMJ rejected critics of the ultra-processed food concept who believe the definition has varied over time, that that in modern societies it is unrealistic to advise people to avoid ultra-processed foods, and that reformulating the nutrient composition of processed foods is a more effective way to reduce exposure to risky nutrients such as saturated fat.
“Policy makers should shift their priorities away from food reformulation—which risks positioning ultra-processed food as a solution to dietary problems—towards a greater emphasis on promoting the availability, affordability, and accessibility of unprocessed or minimally processed foods.”
Public health implications
The British Heart Foundation (BHF) said more studies were needed to account for the reasons why studies reveal a link between ultra-processed foods and health risks.
Victoria Taylor, senior dietitian at the BHF, said: “It’s important to remember that observational studies like these can only show an association. They cannot tell us what is behind this. The classification of ultra-processed foods used by the researchers is very broad and so there could be a number of reasons why these foods are being linked to increased risk to our health, for example nutritional content, additives in food or other factors in a person’s life. Before we consider making any changes to advice or policy it is important to understand this thoroughly.
“We already recommend people adopt a Mediterranean style diet which also happens to include plenty of minimally or unprocessed foods such as fruit, vegetables, fish, nuts and seeds, beans, lentils and wholegrains. This along with exercising regularly and not smoking has been shown to be beneficial for lowering risk of heart and circulatory disease.”
Meat tax implications
The Food Ethics Council, in response to the studies, repeated its call for a tax on ultra-processed meat.
Dan Crossley, Executive Director, said: “We shouldn’t lump all meat into the same basket, which is why a blunt tax on meat won’t work. The clearest evidence is against ultra-processed meat and other ultra-processed foods, which have been allowed to dominate our daily diets. It’s time to challenge this and seriously consider the idea of an ultra-processed food tax.”
Meat taxes have been discussed in parliaments in Germany, Denmark and Sweden, although it is something currently ruled out by the current UK Environment Secretary Michael Gove.
Sources
‘Ultra-processed food intake and risk of cardiovascular disease: prospective cohort study’
British Medical Journal
DOI:10.1136/bmj.l1451
‘Association between consumption of ultra-processed foods and all cause mortality: SUN prospective cohort study’
British Medical Journal
DOI:10.1136/bmj.l1949