Displacement

Where does free will stop, and frittata begin?

Last week during gaps between appointments I reviewed a few old posts and started to doubt the dubito cogito sum I borrowed for the recent sundowner article (1). Descartes was describing the autonomy of reason, but from there by easy stages I drifted over to the autonomy of self.

Displacement is one of our common defences against a cruel world. It can be an effective coping mechanism but it makes us less authentic and it reduces our autonomy. Displacement is relatively easy to recognise, and there are recognised methods for undoing it, but there are other ways in which we are displaced from ourselves which are more insidious.

While working on these and other projects I have become increasingly aware of the extent to which we are influenced and displaced by our exposome, by what we consume and by our many microbial passengers. The world invades us. Our moods, personalities, cognitive abilities, behaviours and choices are all manifested by a neuronal substrate which, while multiply buffered from the outside world, is still substantially affected by it.

The idea that we can self-regulate and become the true author of our actions shades off, at the edges, into a sense of authority that is at best ambiguous. Can our behaviour ever be fully self-endorsed when it is influenced by past experiences, social context, current circumstances and our genetic profiles?

These formative and informing influences cannot be easily altered, but there are a further three overlapping displacement factors which are well within our grasp; our microbiota, nutritional status and epigenetic status (2, 3). It is on these that I focus.

We are collective organisms after all, our mammalian cells are a minority among the bacteria, viruses, fungi, archaea and parasites which form a complex and critically important system (the microbiota) that affects us metabolically, epigenetically and psychologically. They displace us from the center of ourselves.

Microorganisms in our intestines and other tissues modulate our mood and stress levels (4-13), anxiety, impulse control and aggression (12-18), and therefore sociability (19-20). They affect sex hormones, and therefore sex-related behaviours (22-24). They affect our attitudes towards risk-taking (25, 26) and resilience (27), and therefore our career paths. They impact on our life expectancy and the way in which we die (1, 28).

By changing our diet we alter the colonic microbiota, leading to multiple down-stream effects. Prebiotic fibers, for example, up-regulate saccharolytic species which trigger significant changes in gut hormones. They up-regulate GLP-1 (29), and olive oil may exert a similar effect via a somewhat different mechanism (30).

These hormonal changes reduce hunger via peripheral and central mechanisms, combining slowed gastric emptying with attenuated reward-related brain activation (31, 32). The latter could explain emerging evidence that Ozempic may reduce other impulses / reward systems which overlap with hunger, including addictive and obsessional behaviours (33-38).

This appears to converge with other findings showing that the microbiota have distinct effects on the tendency to develop addiction (39-42), making this yet another area where diet, the microbiota, personality and behaviour overlap

Sexual attraction comes into play here too. From a microbe’s perspective, increased socialising is good for transmission to new hosts but intimate contact is generally better (43). There is pre-clinical and some clinical evidence that mating preferences are affected by the microbiota (44-46), among which several species have learned to produce oxytocin aka the ‘love hormone’ (47).

It’s easy to see how this array of micro-modifiers likely influences the choices we make, the actions we take and the consequences we then face, creating markers which cast long shadows down the years of our lives.

Other nutritional displacers act on us directly, rather than via modulation of the microbiota.

The usual suspects include iron, iodine, zinc, magnesium, a handful of B vitamins, choline, omega-3 fatty acids and vitamins D and C. All have been linked to mental health issues, with deficiency symptoms ranging from depression to impaired intelligence. A diet depleted in one or more of these micronutrients (i.e. the industrial diet) must therefore also reduce us.

More generally, hunger and thirst are nutritional issues, and both hunger (48) and thirst (49) elicit negative psychological reactions which, one could argue, contribute to displacement from oneself. Then there are the well-worn paths of coffee, sugar, nicotine, alcohol, the psychotropic meds over-prescribed by drug reps masquerading as doctors and the recreational drugs flooding our streets.

(Human history, from the development of the spice routes to the global success of the CIA’s drug cartels (i.e. 50, 51) shows how avidly we seek displacement from this, the best of all possible worlds.)

From diet it is a small step and a single letter to epigenetics. The epigenome is profoundly affected by what we eat (i.e. 52, 53), and arguably the modern diet, which does not provide the epigenetic support supplied by a traditional diet, reduces us via epigenetic mechanisms also.

The nutrient-dense traditional diet provides an array of compounds, predominantly derived from fruits and vegetables, that can inhibit or even reverse epigenetic changes associated with ageing and the progressive loss of functionality. Phytochemicals from cruciferous vegetables such as broccoli and cabbage, as well as polyphenol-rich foods like the teas and berry fruits slow physiological (52-54) and epigenetic ageing (52-54), and improve our mental well-being (55-60).

Some of these positive mental effects may be due to reduced neuroinflammation, but it is likely that the epigenetic changes induced by such foods also play a role in the health and activities of the central nervous system; they are certainly involved in memory formation and storage (61-64).

It goes further than that. The burgeoning new science of behavioral epigenetics, which traces the complex relationships between diet, epigenome and personality (65-68), indicates that core aspects of our personalities may be profoundly affected by epigenetic factors (65-71). This novel twist on the old idea that we are what we eat describes yet another level of displacement.

Stress plays into this too. Chronic stress affects the epigenome, particularly genes involved in the stress-responsive hypothalamic–pituitary–adrenal axis (69-71), that persists into future generations and harms their ability to deal with stress, including nutritional stress (72).

Where traditional diets were epigenetically positive and stress-alleviating diets, it seems likely that today’s calorie-dense but nutrient-lite diet, combined with a low-energy lifestyle, exacerbates the epigenetic effects of stress (67, 69-71, 72). Pre-clinical work with inter alia baboons (72, 73) likely has meaning for men, women and everything in between.

These developing insights help to explain why today’s children, a generation down-stream from the triumph of fast and ultra-processed foods, are so very prone to stress, depression, anxiety and overweight. They also provide another reason why our abject legislators should abandon their necropolitics and do more – do anything – to protect our young ones, allowing them to express their biological potential and be more their true selves.

It is not just food. Exposure to sunlight (74) and to nature (75), has marked positive effects on mental health; as do beautiful locations in general (76), whether these are natural or constructed. We must reintroduce more nature and more beauty into our urban blighted lives if our species is to blossom.

These are not new ideas. Victorian society had the will to alleviate the negative mental and physical impacts of crowded urban living, especially amongst the poor, and they understood the basic human needs for sunlight, beauty and sound nutrition (77, 78). They legislated for better food, slum clearance schemes, physical education in schools, free municipal art galleries and museums, daylight access via the Sunlight Movement, urban parks and Green Belts around cities to ensure urban dwellers had access to nature for their health (78).

Today, in Britain and the United States I regularly encounter children living in food deserts who have been raised exclusively on fast and ultra-processed foods. Visibly unhealthy and riddled with inflammation and mis-behaviour, they are hard (not impossible) to reach, and very resistant to dietary improvement. It is almost as if their abnormal microbiota and epigenomes instruct their owners to remain inflamed …  while all the fire exits provided by Victorian society are long gone.

Some Victoriana are returning. In this vulnerable group scurvy, rickets and frank malnutrition are all staging a come-back (79-81).

How far the political degenerates of our era have fallen.

I am straining at a gnat, but my general point is that autonomy of self is gained and ceded from many directions, and we are continually displaced from our core selves by primary and secondary exposomal factors.

Some are inaccessible but the nutritional, microbial and epigenetic sub-sets at least are relatively malleable. By optimising them it should be possible to create a platform of metabolic, neurological and epigenetic stability from which truer and more robust lives might be enabled, lives less vulnerable to external traps and tripwires.

We could build back better. For real, for once.

Next week: Night of the Hunter: displacement, crime and punishment.

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