The food pile criticality hypothesis: nor carnivore nor vegan.
Per Bak’s sandpile model stands as an insightful abstraction and seminal work on statistical physics, offering a lens through which to comprehend one of the main properties of complex systems, the self-organized criticality (SOC).
Consider a lattice or grid where each point signifies a site. Introduce sand grains onto these sites, incrementally building a pile. At a certain threshold, a site becomes unstable, initiating a toppling event. The toppling redistributes one grain of sand to adjacent sites, potentially triggering further instabilities and creating an avalanche effect.
A pivotal facet of the model is the interaction among neighboring sites during a topple. The transfer of sand from an unstable site to its neighbors not only mirrors physical phenomena but also encapsulates the interdependence inherent in natural systems. The model captures both orthogonal and diagonal interactions, reflecting the nuanced connectivity seen in real-world networks.
The consequence of a single site’s instability, manifested through an avalanche, is a hallmark of the Bak sandpile model. These avalanches exhibit a power-law distribution, a key feature of critical systems. From minor disturbances to large-scale events, the model accommodates a spectrum of outcomes, mirroring the unpredictable nature of real-world critical phenomena.
As the system evolves, it converges towards a steady state, teetering on the brink of stability. This critical state is characterized by a delicate equilibrium, where minor perturbations can lead to cascading events of varying magnitudes. The system achieves a poised balance between order and chaos.
This power law behavior is the statistical fingerprint of scale invariance, one fundamental symmetry of complex systems and that has been widely described by Geoffrey West book, Scales.
Criticality
“The Criticality Hypothesis, states that systems in a dynamic regime shifting between order and disorder, attain the highest level of computational capabilities and achieve an optimal trade-off between robustness and adaptability28. In this framework robustness is associated with order and self-organization, meanwhile, adaptability is related to disorder and information emergence, as we will discuss below. Empirical evidence has related human health to heart, and brain criticality29,30,31,32, and loss of criticality (mainly by loss of adaptability) with chronic diseases (such as obesity or diabetes) and elderly process33. In their work, Huitzil and co-workers (2018)27 claim that microbiome and genome networks are critical networks which means that their dynamical behavior is at the brink of a phase transition between order and chaos34,35. This idea is supported by the facts that dynamical criticality confers the system properties such as evolvability (i.e., the coexistence of robustness and adaptability)36,37, faster information storage, processing, and transfer38,39, and collective response to external stimuli without saturation40; and in fact, there is solid evidence indicating that gene regulatory networks of real organisms are dynamically critical or close to criticality41,42,43,44.” Ramírez-Carrillo et.al. 2020 -> https://www.nature.com/articles/s41598-020-60562-w
Even more the existence and ubiquity of critically has been recognized as one of the classic problems in complex systems. Another universal characteristic of complex systems is their Antigrafility or the capacity of taking advantage from environmental randomness.
In that sense, living systems need to perceive, respond to environmental perturbations, and interact with other similar entities. Biological systems constantly try to encapsulate the essential features of the huge variety of detailed information from their surrounding complex and changing environment into manageable internal representations, and they use these as a basis for their actions and responses. The basic data to decision process implies
Acquire data -> perform computations over the data acquired-> make inferences -> construct models -> make decisions. Then it is clear that given that when a system is in criticality it achieves the greatest capacities to perform computation and inference, then it also at a best in modelling and therefore to respond to environmental perturbations, which is maximum Antifragility.
The connection with diet
In a previous essay I’ve already make the case of Why I won’t say no to meat but since then we have been making some progress understanding the role of diet and systemic health determined for example by the correct functioning of gut microbiota ecosystem.
Diet, we found, is not just about physical health but intricately shapes the connection between the gut microbiota and the nervous system. We aimed to uncover how ecological pressures mold the intestinal microbiota and its impact on various bodily functions, particularly focusing on brain functionality at different life stages.
There is an important amount of studies that shows how gut microbiota interacting with biochemical processes in the gut, establishes a sophisticated network of bidirectional communication with the brain in what has come to be known as the microbiota-gut-brain axis.
At the epicenter of the gut-brain axis lies the enteric nervous system, colloquially recognized as the “second brain.” Operating autonomously yet in constant communication with the central nervous system, the ENS forms a neural network within the gastrointestinal tract. Facilitating this intricate communication is the vagus nerve, a pivotal cranial nerve orchestrating bidirectional signaling between the gut and the brain.
Neurotransmitters, including serotonin and dopamine, serve as primary messengers in this elaborate communication network. Hormones such as ghrelin and leptin, integral to hunger and satiety signaling, contribute additional layers of complexity. Noteworthy is the role of the gut microbiota, a consortium of microorganisms residing within the gastrointestinal tract. These microbial entities produce bioactive molecules capable of modulating the nervous system, thereby exerting influence on cognitive functions.
The gut-brain axis governs a diverse array of physiological functions. From regulating appetite and energy balance by informing the brain of digestive processes to influencing mood, emotional states, and participating in stress responses, this axis is a nexus of systemic regulation. Its involvement extends to the modulation of inflammatory responses and the intricate orchestration of cognitive functions, including memory and learning.
The gut microbiota-brain axis is a complex system that integrates endocrine, immunological, and neuronal signals between symbiotic microorganisms, the gut, and the brain [1]. Here, the host’s diet can be a fundamental factor for the functioning of this axis, especially during critical developmental windows for the gut microbiota (GM) and the brain [2, 3]. Maturation of both systems occurs in parallel, and childhood is one of the most dynamic periods of change. Thus, the GM interaction with the host diet during such critical periods has the potential to alter brain-gut signaling profoundly, affect health throughout life, and even increase the risk of neurodevelopmental disorders. For instance, during this age, the ecological dynamic of bacteria that compose the host’ GM reaches a maturity that resembles an adult GM, incrementing total diversity and abundance and establishing strong symbiotic mutualistic relations with their hosts. For the brain, it causes the elimination of the extra synapses, decreasing cortical gray matter levels, and the formation of new neuronal connections producing a phase of high plasticity throughout much of the brain [4]. On the other hand, enhanced nutrition incorporating nutrients of animal origin, such as protein and lipids, during these windows of neurodevelopment might have a lasting effect on behavior and cognition in adulthood. For instance, increasing animal protein intake during the first week after birth may protect preterm children’s brain structural and functional development. In the same way, serial Magnetic Resonance Images from birth show that animal lipid and protein intake during the first few weeks positively predicted larger brain volumes and cognitive outcomes at 18 months [5]. Moreover, certain dietary deficiencies present in animal products during the first two years of life, such as iodine or iron, create adverse cognitive effects that are not reversed by a later adequate diet [6]. Additionally, animal protein-energy malnutrition is responsible for more specific damage to the hippocampus and cortex [7]. Animal lipids, in turn, are essential for synthesizing neuronal membranes, in the construction of several neural structural elements such as myelin, in the production of signaling components, and are solvents of a wide variety of non-polar extracellular and poorly soluble cellular constituents [8]. Beyond these aged-related effects, the two nutrients consumption continue to influence cognition by acting on molecular systems or cellular processes vital for maintaining brain functioning [9]. https://journals.plos.org/plosone/article?id=10.1371/journal.pone.0281385
Our research has generated some initial evidence suggesting that a childhood diet deficient in animal proteins and lipids could compromise the body’s “antifragility,” diminishing its adaptive capacity. This term reflects on a loss of both gut microbiota and brain activity connectivity that translates in a loss of the organism’s ability to self-organize and benefit from disturbances, crucial for overall health.
In the same way we have found (see Santoyo et.al. 2023) that specially during childhood, that is a key age for gut microbiota and brain maturation, an industrialized urban lifestyle produces a similar loss in criticality/antifragility.
From these studies and the general reasoning about Why I won’t say no to meat, it is clear for me that a vegan diet is not a healthy one, but how about a complete carnivore?
Well, the reason why I spent more than a few paragraphs making the case for the importance of a Criticality / antifragility framework is because once we understand these are universal principles for living systems, and how they apply for example to the health of the microbiota-gut-brain axis, we don’t require to show a myriad of studies explaining why one diet is better than another, we can simply deduce implications from the necessity of the organism to be at criticality / antifragility. Of course our deductions must be in good agreement with all rigorous studies on the topic. But I found very educative to change the way of argumenting from data based to principles based.
The food pile criticality hypothesis
Hypothesis: In order to maintain the organism antifragility, especially through the gut microbiome ecosystem; the organism requires such a diet that provides scale invariant nutrient’s fluctuations time series in a good balance between emergence and self-organization.
If we can measure a systemic physiological time series (i.e. electrical heart activity) and then we calculate its fluctuations (taking away mean and cyclic behaviour) then this fluctuation times series is a good caracterizatión of the systems dynamics.
In general terms we can perform some mathematical transformations to these fluctuations time series data, the systems dynamics, (see Ramírez-Carrillo et.al. 2028 and the video below) to see it not in the time domain but in the domain of frequency. Beyond any tecnicality, if the system data under this mathematical transformation resembles the behavior of the blue line (white noise), then the system is characterized by randomness; if it resembles the green line (brown noise) the system is characterized by order; and if it resembles the pink line (Pink Noise) then the system is at criticality (the fingerprint of complexity).
As I have pointed put before, this special kind of danimcis called criticality is a key feature of health. Under this dynamics the system exhibits fluctuations (changes from mean value) of every size. Some times the systems exhibits very large values, sometimes low, but the exact statistical way this occur is given by the above mentioned mathematical transformation that follow a power law in frequency space.
In this way, the food pile criticality hypothesis means that if we could measure all important nutrients from our meals register their values in time (construct a nutrient time series) and then perform this kind of analysis, we could classified our diets on ordered, random or at criticality. As health is associated to criticality, and in these case the nutrients time series would be inputs for the systems, what the hypothesis consider implicitly is that in order to the organism to be in criticality it requires that its corresponden inputs also be at criticality.
This is also a requirement discussed in detail in Antifragile book by N. N. Taleb in which he state that antifragility is achieved under the correct ype un perturbations. As the author put it, organisms need some perturbations to be healthy but too much also takes them out of health, what correspond to a dosis-response profile of perturbations.
So a complete random or too ordered diet should eventually take the organism out of health. This is the case for both veganism, or strict carnivore diets.
If you have been under western industrialized diet, that we have showed diminishes organism’s antifragility, and perturbate it by either changing to carnivore or vegan, most likely you will get short and medium term benefits for your health. Long term is not clear, and following the reasoning about criticality one would expect that under both people would loss health with time. How fast and the magnitud of that loss may depend on previous health before the change, other factors as exercise, stress and so on, and of course genetics.
So if not western industrialized, vegan or carnivore, how does a systemic healthy diets looks like?
Fortunately this kind of questioning is not new ant different cultures has gone trhough a try and error processes of centuries and have encode their results in traditional diets. One excellent example of this because if very well documented is the Orthodox church diet calendar as shared by Naleb in his X account.
So, evidence and theoretical reasoning points to that most likely we need a diet that some time is vegan, sometimes carnivore and many times omnivore + some fast.
