We have long grown accustomed to reading the labels and determining the worth of a food by its salt, sugar and fat content.
The savvy amongst us may look for certain ingredients such as high-fructose corn syrup, artificial colours or hydrogenated oils. These sort of ingredients are often found in a class of foods known as ultra-processed foods, and they are the new villains of three recent studies.
The leading study
Cell Metabolism published a study in mid-May 2019 that links highly processed foods to weight gain. In this study, 20 people were placed on a special diet of either highly processed or unprocessed foods for two weeks, before they switched to the other type of food for two weeks. The foods served were not restricted, meaning the participants were able to indulge in as much or as little as they felt like eating on their given diet. Interestingly, the servings were matched as much as possible for calories, carbohydrates, protein and sodium. Participants reported that both diets tasted good.
The results are not surprising. Participants ate more when on the ultra-processed portion of the diet and gained weight and body fat. This makes sense when you think about it. Raw foods tend to be more work when it comes to chewing them, and the longer it takes to eat, the more likely you will realise when you are no longer hungry.
Is there anything else to it?
There are now two more studies, just released. These European studies looked at the amount of ultra-processed foods consumed by a large number of participants and tracked the health outcomes for some time – a French study (2009–2018) and a Spanish study (1999–2014).
A higher consumption of ultra-processed foods (>4 servings daily) was independently associated with a 62% relatively increased hazard for all-cause mortality. For each additional serving of ultra-processed food, all-cause mortality increased by 18%.
– The BMJ
It seems it is not simply a case of your eyes being bigger than your stomach.
What is an ultra-processed food?
There is a NOVA classification system by the UN for grouping foods by their processing rather than in terms of their nutrients. A thorough explanation of NOVA can be found at Open Food Facts.
The NOVA food classification system:
Group 1: unprocessed and minimally processed foods – fruit, vegetables, nuts, meat, eggs and milk. May be dried, pasteurised, cooked or chilled.
Group 2: processed culinary ingredients – oils, butter, sugar and salt. Processed to make products that can be used to cook Group 1 food, but not meant to be consumed by themselves.
Group 3: processed foods – preserved fruit and vegetables, tinned fish, cheese and fresh bread. Usually made from two or three ingredients.
Group 4: ultra-processed foods – soft drinks, packaged snacks, reconstituted meat and preprepared frozen meals. Contain little, if any, intact Group 1 foods. Include ingredients like sweeteners, colours, preservatives and food-derived substances like casein, lactose and gluten.
Source: Open Food Facts
Examples of Group 4 foods:
carbonated drinks; sweet or savoury packaged snacks, ice cream, chocolate and candies (confectionery); mass-produced packaged breads and buns; margarines and spreads; cookies (biscuits), pastries, cakes and cake mixes; breakfast cereals and cereal and energy bars; energy drinks; milk drinks, fruit yoghurts and fruit drinks; cocoa drinks; meat and chicken extracts and instant sauces; infant formulas, follow-on milks and other baby products; health and slimming products such as powdered or fortified meal and dish substitutes; many ready-to-eat products including preprepared pies and pasta and pizza dishes; poultry and fish nuggets and sticks; sausages, burgers, hot dogs and other reconstituted meat products; powdered and packaged instant soups, noodles and desserts
If a product is in Group 3 but has added ingredients such as artificial sweeteners or emulsifiers, they are moved to Group 4.
Drinks produced by fermentation are also in Group 4 – think whisky, gin, rum and vodka. We question this inclusion, not only for our own drinking habits! For example, kombucha is a fermented drink, but it doesn’t seem to fit into this category.
Another interesting inclusion is infant formula and milks. We doubt anyone is willing to suggest you should stop using these.
Naughty additives include:
casein, lactose, whey, gluten and some derived from further processing of food constituents such as hydrogenated or interesterified oils, hydrolysed proteins, soy-protein isolate, maltodextrin, invert sugar and high-fructose corn syrup. Classes of additives found only in ultra-processed products include dyes and other colours, colour stabilisers, flavours, flavour enhancers, non-sugar sweeteners and processing aids such as carbonating, firming, bulking and anti-bulking, defoaming, anti-caking and glazing agents, emulsifiers, sequestrants and humectants
What is interesterified fat?
Interesterified fat is a type of oil where the fatty acids have been moved from one triglyceride molecule to another. This is generally done to modify the melting point, slow down rancidification and create an oil more suitable for deep-frying or making margarine that tastes good and has a low saturated-fat content.
Yeah, that doesn’t sound good.
Does this apply to plant-based burgers?
Most plant-based burgers contain soy-protein isolate and a good number of texture and flavour enhancers.
Impossible Burger 2.0 ingredients:
water, soy-protein concentrate, coconut oil, sunflower oil, natural flavours, 2% or less of: potato protein, methylcellulose, yeast extract, cultured dextrose, modified food starch, soy leghaemoglobin, salt, soy-protein isolate, mixed tocopherols (vitamin E), zinc gluconate, thiamine hydrochloride (vitamin B1), sodium ascorbate (vitamin C), niacin, pyridoxine hydrochloride (vitamin B6), riboflavin (vitamin B2), vitamin B12
That’s a pretty solid yes – Impossible would be placed in Group 4.
The Beyond Burger ingredients:
water, pea-protein isolate, expeller-pressed canola oil, refined coconut oil, 2% or less of the following: cellulose from bamboo, methylcellulose, potato starch, natural flavour, maltodextrin, yeast extract, salt, sunflower oil, vegetable glycerine, dried yeast, gum arabic, citrus extract (to protect quality), ascorbic acid (to maintain colour), beet extract (for colour), acetic acid, succinic acid, modified food starch, annatto (for colour)
Beyond is in Group 4 too.
Let’s look at a typical soy milk ingredient list…
Soy milk ingredients:
water, soy protein, maltodextrin (from corn), canola oil, sugar, acidity regulators, emulsifier, thickener, stabilisers, natural flavours, vitamins (B2, A, D, B12)
Packaged soy milks and almond milks are also in Group 4. Make your own nut milk to put it into Group 1.
So are the plant-based alternatives out?
Don’t go nuts, but there needs to be room for common sense. There is a lot we don’t yet know about how these ultra-processed foods are affecting us, and we should also consider what alternatives we are eating (possible heavy metal accumulation, hormones and antibiotics in meats, for example).
The first study suggests that it was the proportion of these types of foods rather than the risk nutrients (e.g. saturated fat) that caused the weight gain. But a four-week study where participants ate more of one food type (which is easier to eat quickly) and then experienced weight gain is not the definitive answer. We need to know why the last two studies showed a large increased hazard for all mortality types with increased Group 4 consumption.
More should and will be done to explore what it is that is negatively affecting our health the more we eat these types of foods.
In the meantime, we would do well to reduce Group 4 snacks for our kids (sausages, biscuits, packaged breads, for instance) and have some blanched veggies on hand at all times.
Also, remember that if you stick solely to foods in Group 1, you won’t live forever, but it might feel like it.