Post No.: 0767
What makes highly processed or junk food particularly yummy compared to even ripe and sweet fruit on its own for many of us?
It’s strongly arguably the combination of fat and sugar (or more generally fat and carbohydrate) that’s so ‘addictive’. Just eat a dollop of fat on its own or a lump of refined sugar on its own and it’s either dreary or sickeningly overpowering. (You could perhaps try it as an experiment!) Hence we won’t likely become obese this way.
But process them together – especially in a ~1:1 ratio – and one’s appetite can become nearly insatiable. And that’s how most people in the modern world who eat modern processed foods usually become obese if they become obese.
Even savoury snacks, like crisps and crackers, contain a combination of fat and carbohydrate (most things that are deep fried do), and they come a close second to fatty and sweet items, like cookies and chocolate.
And this craving for a combination of a fatty, creamy mouthfeel and sugary sweetness, especially in roughly equal proportions, is a craving for a processed mix that is rarely found naturally in any known source of food or drink in nature – except for breast milk.
So, putting two and two together, it appears that unnatural processed foods and drinks (e.g. ice cream, milkshakes, fried chicken with barbecue sauce, chips with dips) are what can interfere with our reward systems and our natural ability to successfully self-regulate our appetites. And it’s this kind of stuff that we tend to eat not just purely for sustenance but whenever we graze or mindlessly snack – it’s simply for the pleasure of the taste, not for the nutrients. Therefore perhaps this synthesis of fat and sugar in roughly equal ratios is what we can class as an addictive substance? (Please read Post No.: 0761 for more on this debate.) Woof.
The combination of fat and salt is also hard to resist. The ‘bliss point’ of deliciousness (or ‘drool point’ as I call it) is achieved with the right balance of fat, sugar and salt. Flavour enhancers like monosodium glutamate also help. You may be surprised how many savoury snacks have added sugar, and how many sweet snacks have added salt.
The human genome has not significantly evolved much over the past 50 years or so to make present generations of people suddenly less moral and more lacking in self-control. It’s the modern environment of highly or ultra-processed foods that has been a key change during this very time period that correlates with the sudden, steep rise in obesity rates.
Older generations of people didn’t face such environmental temptations as much, especially during their development or upbringings. (It’s arguably the same with the increase over time in fun sedentary activities and other factors like parents being more afraid of letting their children out to play because of increased traffic on the streets.) If they did as children during their own formative years, they’d also have highly likely fell for these temptations more frequently too.
Ultra-processed foods are relatively cheap to mass produce, more profitable, and are thus more heavily marketed than less processed foods too. Manufacturers specifically target that ‘bliss point’ when developing their products. They’re looking for that moreish fatty mouthfeel, that appealing crunch and/or that soft easy-to-wolf-down texture, that makes these calories easier and quicker to consume. It’s probably more than just the fat, sugar and/or salt content but the way and extent to which such food is processed? It could be the combination of particular additives too? It all seemingly affects the brain to make it more receptive (addicted?) to wanting even more processed foods. If so, it’s like there has been a kind of brainwashing program that food corporations have been selling to the masses and profiting hugely from over the past several decades so far. Addiction never serves us – it serves the businesses that profit from selling the addictive product.
‘Hedonic escalation’ has also been proposed as a theory to explain why foods with more complex flavours (e.g. sweet and sour, salty and sweet) make us want to try them again and again compared to simpler flavours, in order to fully capture that complex experience. This can mean such foods are more addictive or ‘addictive’ – especially those that are sweet, fatty and salty, such as salted caramel sweets when the balance is just right, which goes back to the ‘bliss point’.
Although it’ll take longer than foods with simpler flavours, we will eventually get bored of such foods too and want to try something else. Yet this is why the most perilous thing for one’s diet is having a variety of highly calorific foods with different flavours presented in front of our gaping maws (like a party spread). And that’s why what a lot of people do is constantly switch from savoury snacks to sweet snacks, and back, and so forth.
Food is far more than just about nutritional sustenance. It’s pleasure. It’s morale. (It’s thankful that army field rations have improved over the years!) Yet when eating becomes divorced from its nutritional purpose – health problems can arise. This is one example of how evolution has crudely linked ‘it’s generally advantageous for our survival to do a particular thing (seek and consume energy-dense foods in this case) hence those who had the chance mutation, the allele, the genotype, the phenotype, that found it rewarding to their brains to want to do that thing more often were more likely to survive and in turn reproduce and consequently pass this instinct onto future generations’ – which was fine before highly processed foods were so commonplace in the environment – but now in this world of highly processed temptations everywhere on the high streets, and now from apps we can use to order such stuff without even needing to get off our (ever chubbier) bums, our modern societies are experiencing widespread problems like obesity. This shows us how an evolved instinct that was healthy for one kind of environment can ironically turn severely unhealthy in another. More is not necessarily better – that’s (merely) one instance where caveperson instincts have gone unquestioned and unchecked in a very different world of convenience and plenty for many.
Under-eating is a serious health problem that shouldn’t be ignored too. But excess fat and sugar (and alcohol) intake still leads to the significant health problems linked with obesity that we’ve known for years, like type 2 diabetes, heart disease and cancer. The finding now is simply stating that we won’t tend to consume excessive amounts of fat or sugar unless they are served mixed together in roughly a 1:1 ratio calorifically, such as found in many highly processed foods.
It’s like chopping an onion can still cause an injury, or riding a motorcycle can still cause an accident and therefore an injury – but you won’t tend to cause any injury to yourself doing these activities unless you combine those two activities together! Or more relevantly, most people will eat more if they are given fried chips with ketchup than if they are given just the chips without any ketchup or if they are given just the ketchup without any chips or anything else that’s fried to dip into it. People will eat less if they are given fried chips, fried chicken or burgers without any sauces or relishes. It helps explain why most people can gorge almost endlessly on biscuits, puffed corn snacks, chocolates and cake, compared to boiled sweets or pork scratchings. Otherwise healthy nuts become even more moreish once coated in honey or something sweet, and a bit of salt too.
Yet it’d be misguided to go on a diet that cuts out either fat or sugar wholesale. There are many reasons why totally cutting out carbohydrate or fat from your diet can be detrimental. Cutting out fat, especially HDL fat sources, like olive oil, can increase the risk of high cholesterol. When we eat a lot of fat, we tend to eat it with protein too, and this can make us feel fuller, and fuller for longer, than when compared to consuming a carbohydrate-only diet. Consuming protein from any source may help banish cravings better than carbohydrates – so we’d have a harder time feeling sated if we were to try to completely eliminate fat, and consequently some protein, from our diet.
And a diet without sugar can mean that we’ll feel sluggish and lack concentration. Mammalian brains run primarily on glucose. When your body doesn’t have sufficient carbohydrate available, it will convert fat and then protein into glucose (gluconeogenesis), but this process itself takes energy, and burning protein for energy will mean burning muscle mass. Cutting out sugar can still lead to diabetes – possibly even more so – because our bodies can react by becoming insulin resistant and thus it’ll make more insulin to compensate.
Losing weight may mean you’ll lose a bit of fat (or it could mean you’ve just temporarily lost some water). But it could also mean you’ll lose a fair bit of muscle mass too if your diet is either high-fat and low-sugar, or high-sugar and low-fat, or low-protein. We need the right amount of protein, especially if we exercise, in order to repair and build our muscles. Exercise, in turn, is necessary to maintain muscle mass, as well as not completely eliminating either sugar, fat or protein from your diet. More muscle mass means a higher basal/resting metabolism too, all else being equal.
No single macronutrient or micronutrient is therefore a saint or a sinner – you’ve got to look at your diet holistically. And related to this, no fad diet is therefore really healthy – no diet that excludes any macronutrient or micronutrient, or concentrates too much on any macronutrient or micronutrient, is optimal for us, or our wallets.
So it’s not about just eating fat and not sugar, or just eating sugar and not fat, in your diet – we need both to be healthy. It’s about not eating too many processed foods and snacks because they’re more addicting. Food developers will have finely-tuned the taste and mouthfeel so that they’re simultaneously sweet and creamy or crunchy. Homemade cooking can take advantage of more complex herbs and spices to achieve an exciting flavour, which not only don’t carry well in processed foods (the processes in mass manufacturing destroy much of the taste of herbs, and the flavour of some spices can fade over time i.e. when stored, transported and left on the shelves in supermarkets) but sugar and fat is a far, far cheaper way than herbs and spices to achieve taste and maximise profits from. The physical activity of cooking itself uses up more calories than buying or ordering convenience foods or take-aways. Processed foods often require less chewing too precisely because of their processing (e.g. minced meat), and of course chewing itself uses some calories. Therefore, with processed foods, you’re gaining more net calories compared with a fluffy home-cooked meal via these ways too.
One could possibly try consuming a breakfast of sweet things, a lunch of fat things, and a dinner of both. But that might not be exciting for breakfast or lunch, which means one may gorge on dinner. If drinking a sweet beverage, don’t eat fatty snacks with them. In-season fruits are much healthier than processed snacks. Administering manual or mindful self-control rather than autopilot or mindless munching might make a difference too now that you know what the true enemy is – if your goal is to lose or not gain weight.
Woof! There’s still no sign of a magic bullet, no cheat codes, to conquer the obesity crisis without the risk of side-effects and/or additional costs. The answer is consistently the same as ever – a balanced, varied diet and regular exercise. But now we think we understand the true number one culprit – processed foods that contain high levels of sugar and fat in a ~1:1 ratio calorifically.