One of the many problems built into today’s fast foods is that they are too fast. They are manufactured on breathless assembly lines which whip past the few maintenance workers still on the shopfloor, and disappear into the distance. Liquids, pastes and powders containing carefully calibrated doses of sugar, starch, plant oil, salt and other ingredients are blended in a rigidly controlled sequence and the resulting slurry is excreted, equally accurately, into endless molds on endless belts which lead to endless ovens or chillers. This is how pet food is constructed, and human kibbles too such as cookies, cakes, chocolate bars, ice cream, candies, yoghurts, sodas, breakfast cereals and ready meals.
As various stages of product fly past on the belts, virgin visitors to the food factory tend to be unnerved. This does not in any way resemble a kitchen, any more than an automobile assembly line in East Liberty or Seoul resembles grandpa’s garden shed. And while the finished products still look like food, appearances are deceptive. Not only are they unlike traditional foods in terms of their impoverished nutritional content, they are also very unlike traditional food in terms of their degraded structure.
The structure of food is incredibly important because it affects how rapidly that food is digested and absorbed into the bloodstream. That in turn determines peak plasma levels of nutrients such as sugars and fats, and these numbers have major implications for your health.
After preparation, basic produce still requires a certain amount of chewing because it contains fibers and/or sinew and gristle. Chewing produces a range of particle and droplet sizes, depending on the food and how effectively we chew it. Once these particles and droplets enter the stomach and small intestine digestion begins, at varying rates depending on particle size, their composition and the viscosity of the ingested material.
The overall process is slowed by the complexity of traditional foods; our physiological systems are designed to deal with complexity and slowness, and they function very well on a traditional diet.
In contrast, ultra-processed food does not require much chewing because this has already been replicated in the production process, which is designed to iron out the lumps and bumps. Ultra-processed food has a largely homogeneous consistency, and after minimal chewing pours into the small intestine where digestion and absorption are accelerated and compressed into as little as an hour. Where traditional foods cause slow and low plasma curves of the different nutrients, ultra-processed foods produce fore-shortened and mountainous peaks of sugars, triglycerides and other compounds in the blood stream 1-4). This is not good.
High levels of triglycerides in the blood after a meal are a well-established risk factor for cardiovascular and other diseases (5-8). They increase the risk of disease by triggering a cascade of inflammatory reactions (6, 8, 10, 11-13), causing nitrosative stress (4) and endothelial dysfunction (8, 14, 15). At the same time they lower HDL cholesterol, and increase levels of the highly atherogenic dense LDL particles (16). The post-prandial hyperglycemia which usually coexists with post-prandial hyperlipidemia, given the make-up of most ultra-processed foods, is just as harmful (17). These are just some of the reasons why afficionados of fast foods tend to die young (18).
For the fish oil drinkers, let me add that not all fats are equal. Saturated fats such as palmitic and stearic acid are pro-inflammatory when they reach high levels in the blood, but polyunsaturated fatty acids such as the omega 3 HUFA’s are not (19-22). And of course, very few meals comprise solely of fat. Fat absorption may be slowed and therefore peak lipid levels lowered by other components in the food, such as proteins (23, 24) and polyphenols (25-27).
This is not an argument against ultra-processed foods in general, because if these foods were designed with health as a priority they could be easily amended to smooth and lower the plasma curves (ie 28). This last reference describes adding hydrolysed guar gum to a commercial yoghurt in order to reduce peak lipid levels, making the product less toxic. One could go much further; by adding a blend of prebiotic fibers to ultra-processed foods they could be given better texture and transformed from toxins to veritable health-promoters. Danone, Nestle, Unilever et al – take notice!
While waiting for these companies to develop a social conscience, there are other things you can do to protect your health. Vigorous, aerobic exercise after an ultra-processed meal completely blocks the artery-damaging effects of ultra-processed, high fat foods (29). It has to be vigorous, because lower intensity exercise such as walking is ineffective (30).
Alternatively, you could cut out ultra-processed foods altogether and switch to a Mediterranean diet, which is definitely protective (31). Specifically, a diet rich in high-fiber, plant-based foods such as minimally processed vegetables and fruits, whole grains, legumes, and nuts markedly blunts the post-meal increase in glucose, triglyceride and inflammation. A regime incorporating lean protein, fish oil, calorie restriction and weight loss provides further benefits.
Wholesale lifestyle change is a better option than exercise alone, because there is another speed-related hazard built into ultra-processed foods which aerobic exercise cannot protect against. Returning to the food factories, the overwhelmingly obvious aspect of the process is its speed. In order to produce product cheaply and in large volumes it must be produced quickly, which almost inevitably means using processing at higher temperatures than would be used in most domestic kitchens. The combination of high temperatures and the already toxic mixtures of fats and sugars in ultra-processed foods produces high levels of advanced lipid end-oxidation products (ALE’s) and advanced glycation end-products (AGE’s) (32). These very pro-inflammatory compounds are implicated in many disease states (32 – 35), and even vigorous exercise will not protect against them.
Excessive speed harms us in yet another way, but now I am referring to the speed at which we eat. Because of our rushed lifestyles, increased intakes of ultra-processed foods and our increased tendency to snacking (largely on ultra-processed foods), the duration of our meals has shortened (36-38). 19th century mealtimes were sacrosanct family occasions which easily could last for 90 minutes or more (39). This is no longer the case. There is evidence that average meal times have shortened even in the last half century (37, 38), and may now be as short as 10 minutes (38, 40), with North Americans and Asians clearing their plates first and Europeans eating at a slightly slower pace (41).
When you complete your meal more rapidly, the ingested food arrives in the small intestine over a shorter period of time and plasma peaks of fats and sugars are made even steeper. This probably explains why rapid eating is linked to liver damage (42) and overweight. Eating fast reduces dietary thermogenesis, which means that more of the calories you eat are stored in adipose tissue (43). This might have been adaptive in an age of food insecurity, but in our time it is linked to an increased risk of obesity (44-46).
You can start helping yourself by simply slowing down and chewing more, a strategy shown to aid weight loss (47-50). The mid-Victorians, who were leaner and healthier than we are, recommended chewing every mouthful 40 or even 100 times (51). Although this was perhaps taking the idea a little too far, there was method in their masticatory madness. But there is more that we can do if we act collectively and politically.
Today’s ultra-processed foods are nutritionally defective, and cause obesity, chronic inflammation, Type B malnutrition and dysbiosis. Combine this with their increased content of toxic AGE’s and ALE’s, their accelerated digestibility and our accelerated eating habits, and it is easy to see how the food industry is causing disease and death on an industrial scale.
‘Unsafe at Any Speed’, a book written by consumer advocate Ralph Nader in 1965, revealed the dangers built into automobile design by the sociopaths who ran the car industry (52). Nader showed how car companies resisted the introduction of proven safety features as being too expensive, resulting in death traps such as the Ford Pinto which reliably burst into flames when struck from behind at more than 25 miles per hour. When it transpired that the costs of rectifying the design fault (and saving thousands of lives) amounted to one dollar per car, the public were outraged.
This lead, eventually, to a transformation in the way cars were built; we can thank Ralph for safety belts, head-rests, crumple zones, side impact bars and everything that came after to make cars less dangerous.
Where is the Ralph Nader who will take on the food industry? We need him to rescue us from fast foods. And fast.
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