Performing under Pressure; on the Biology, Psychology and Sociology of stress in high-performance
professions
IX – NUTRITION, STRESS AND PERFORMANCE

On the chaos that is Nutrition Science
uEveryone has their favourite diet and tests it against the standard American diet (MacDonald’s,
Burger king and worse).
uVery few randomised trails
uExtremely complicated to get people to follow a diet
uAnimal studies usually do not translate well
uMostly self-report data (highly unreliable)
u
uMostly aimed at the treatment of disease rather than optimum function
uHeart disease, obesity, diabetes
uWith the exception of sport’s science, longevity research
u
u

The first question to ask:What are you aims?
uNutrition is probably not a question of ‘optimal’ function, but of optimisation for a specific
outcome.
uLongevity
uPeak performance
uPsychological stability
u
u
u
uStress resilience and peak performance?

The second question: what else are you doing/willing to do?
uNutrition does not exist in a vacuum.
uPhysical exercise
uLink with carbohydrate consumption
uSleep
uAffects leptin levels, amongst other endocrine and neuroendocrine systems.
uMental health
uYour mental state may influence metabolism and vice versa.
u

The natural starting point:
What did we evolve to eat?


How far back do we go?
uWhich ancestral species?
uThe further back you go the more fruit and leaves based diet gets (humans are believed to have
first appeared between 300 and 500 thousand years ago).
uAfter the advent of meat eating (at least 2.6 million years ago)
uEnergy surplus
uAfter the advent of cooking (300 000 – 2 million years ago)
uEnergy surplus + gut-size reduction
uAfter the agricultural revolution (+/- 11 700 years ago)
uRise in population, organisation and culture
Wrangham, R. (2009). Catching Fire: How Cooking Made Us Human. New York: Basic Books.
Thompson, J. C., Carvalho, S., Marean, C. W., & Alemseged, Z. (2019). Origins of the human
predatory pattern: The transition to large-animal exploitation by early hominins. Current
Anthropology, 60(1), 1–23. https://doi.org/10.1086/701477
Diamond, J. (2003). Guns, Germs, and Steel in 2003. Antipode, 35(4), 829–831.
https://doi.org/10.1046/j.1467-8330.2003.00357.x

Changes in the food supply
uMany of the foods of the time do no longer exist
u
uSelective breeding of food stuffs
u
uAll year round access
u
uClimate change & the disappearance of species
u

Changes in consumption culture
u3 meals a day with snacks
uThroughout most of pre-agricultural history people went often through short periods (a few days)
of food deprivation, but rarely through starvation.
u
uNon-stop availability
uObesity and diabetes
u
uHigh levels of food-processing
uExcess levels of salt, sugar and unhealthy fats
u
u

What do we actually know about prehistoric diet?
uAtkins, paleo, raw, vegan, carnivore, keto … ????
u
uWe actually know surprisingly little
uGeneralist (all types of food stuffs)
uAn aim at digestibility (cooking)
u
uBut!!!! This diet was consumed in a highly physically active context!
u

Start of meat eating
uClimate change: more grass lands.
uHunting is dangerous and hard. How do you start eating meat?
uScavenging (also rather dangerous but….. BONE MARROW!!!!)
uRemains fresh for a few days because its encaged in a handy little box (bone)
uDoesn’t take complicated tools (a stone)
uHigh in fat
u
Thompson, J. C., Carvalho, S., Marean, C. W., & Alemseged, Z. (2019). Origins of the human
predatory pattern: The transition to large-animal exploitation by early hominins. Current
Anthropology, 60(1), 1–23. https://doi.org/10.1086/701477
Thompson, J. C., McPherron, S. P., Bobe, R., Reed, D., Barr, W. A., Wynn, J. G., … Alemseged, Z.
(2015). Taphonomy of fossils from the hominin-bearing deposits at Dikika, Ethiopia. Journal of
Human Evolution, 86, 112–135. https://doi.org/10.1016/j.jhevol.2015.06.013

Hunting & endurance running
uBig game overheats quicker
u
uIf you can cool more easily, hunting becomes easy.
uNo need for sophisticated tools
uNo need for extreme physical output
Pickering, T. R., & Bunn, H. T. (2007). The endurance running hypothesis and hunting and scavenging
in savanna-woodlands. Journal of Human Evolution, 53, 434–437.
https://doi.org/10.1016/j.jhevol.2007.01.012

Key nutrients
uMacronutrients
u
uCarbohydrates (4cal/gram)
uProtein (4cal/gram)*
uFat (9cal/gram)*
u
uMicronutrients
u
uVitamins
uMinerals
u

Micronutrients
uDeficiencies, and in some cases excess, of a micronutrient may affect both the stress response and
resilience. Regular bloodwork should tell you if you are deficient in anything.
uCommon deficiencies
uIodine
uCalcium
uMagnesium
uVitamins A, B12, D
uIron
uOthers to pay attention to:
uOmega 3 fatty acids (anti-inflammatory)
uAntioxidants
u

Macronutrients
uThe main sources of fuel and building materials
u
uFat and protein are essential
u
uWe can survive without carbohydrates
uEndogenous production of glucose for the brain

The digestive system has specific sensors for different nutrients
uSugars
uWe like sweet things even if you numb taste buds
uStimulates endorphin secretion
uAmino acids (building blocks of protein)
uWe will eat until we have enough, not until we are full
uL-tyrocine (dopamine precursor)
uChicken, turkey, fish, milk, yoghurt and almonds
uTryptophan (serotonin precursor)
uFats (lipids)

The system simplified
uWhat you do not use, you store. But, not all macronutrients are stored the same way.
uInsulin
uFat metabolism
u
uStress releases stored energy
uCortisol
u
uStress for no real reason
uYou dump a lot of energy on the system, remove it, dump it back in, remove it, etc.
u

Serotonin: the relax neuromodulator
uCarbohydrates stimulate serotonin secretion
uRest and digest – relax
uSSRIs – Common anti-depressants but serious side-effects
uBlunted emotions
uDiminished motivation
uDiminished hunger
uDiminished sex-drive

Fasting
uAutophagy
uketosis
u
uLongevity
u
uRegulation of insulin levels
u
uNeurogenesis
u
u
Mattson, M. P., Longo, V. D., & Harvie, M. (2017). Impact of intermittent fasting on health and
disease processes. Ageing Research Reviews, 39, 46–58. https://doi.org/10.1016/j.arr.2016.10.005
Longo, V. D., Mitteldorf, J., & Skulachev, V. P. (2005). Opinion: Programmed and altruistic ageing.
Nature Reviews Genetics, 6(11), 866–872. https://doi.org/10.1038/nrg1706