This is our response to the draft nutrition guidelines.
The timing could not be better actually as tonight I go head to head with the very people who advised on these guidelines. The 3rd Degree piece will be available here (its rightly called “Food fight” after 8.30 tonight NZ time.
Please take the time to read at least the lay summary, and even the full scientific document. I think you will be shocked just how little there is to back up the current and future nutrition guidelines.
It’s time for a full and robust scientific analysis of what we are told to eat to be presented to government health officials (who have it now), and the lay, scientific, and health communities.
We have also proposed a new set of guidelines called the Real food guidelines – real food, for real people, based on real evidence. It’s time to get real people! Here they are for the first time :
The real food guidelines Real food for real people, based on real evidence
Enjoy nutritious foods everyday including plenty of fresh vegetables and fruit.
Buy and prepare food from whole unprocessed sources of dairy, nuts, seeds, eggs, meat, fish and poultry.
Keep sugar, added sugars, and processed foods to a minimum in all foods and drinks.
If you drink alcohol, keep your intake low. Don’t drink if you are pregnant or planning to become pregnant.
Prepare, cook, and eat minimally processed traditional foods with family, friends, and your community.
Discretionary calories (energy foods) should:
a) Favour minimally refined grains and legumes, properly prepared, over refined or processed versions, and boiled or baked potatoes, kumara or taro over deep fried or processed potato fries and chips.
b) Favour traditional oils, fats and spreads over refined and processed versions.
We welcome feedback and scrutiny of our scientific analysis. This is open source and for the people. We are constantly trying to improve our understanding of the science of human nutrition. The evidence changes all the time. Our scientific statement is another iteration in the right direction but should by no means be where we stop. It’s a start..
I had a few things click into place in the last week or two, around how to conceptualize and manage our well-being, especially considering all the biology involved.
Without being grandiose and egotistically naming a theory after myself, I think what I have come up with has some novel concepts. I do acknowledge the inspiration from a scientific paper, which lays out the (some) diet and exercise components of the hormesis of wellbeing (see here).
So here’s a summary of the theory (or at least the bringing together of a few different ideas):
Hormesis is the adaptation to a stimulus which in a bigger dose is toxic. This stress exposure is central to, and even essential for, wellbeing.
Hormetic stressors come form all sorts of things; including sun exposure and our food environments (eg, fasting).
Wellbeing depends on a constant ability to have neuroplasticity (rewiring of the brain). Certain biological conditions must be present for this to occur.
These conditions include high levels of BDNF (brain derived neurotropic growth factor), low insulin, increased IGF-1, and low reactive oxygen specs (ROS).
Hormesis drives these conditions in a similar way across a range of different stressors – too much or too little does exactly the opposite, more or less.
It’s a cool theory I think because it offers some simplicity and parsimony when thinking about the biology of wellbeing and what drives it.
So that’s it in a nutshell and here’s a bit more detail:
What is hormesis?
Hormesis is a theoretical phenomenon of dose-response relationships in which something (as a heavy metal or ionizing radiation) that produces harmful biological effects at moderate to high doses may produce beneficial effects at low doses.
In other words, it’s the theory of general adaptation and super compensation applied across a range of stimuli. Obviously the amount of the stimulus any biological organism can take depends upon its current state (genes plus recent exposures), but also the other stimuli that organism is experiencing. The stress from the different stimuli is likely to stress that same system concurrently (important for later).
Humans need to be exposed to hormetic stimuli to maintain biological function. With no stress, the system adapts backwards as well. If you lie in bed for weeks, or travel into space with zero gravity, your body adapts just as fast as to no stress.
Bottom line: Hormesis is adaptation to mild stress. Stress is not just good but essential to human health and wellbeing.
Can we define wellbeing biologically?
Here’s the next important step. The human nervous system is a complex distributed neural network. It isn’t confined to the head – its throughout your body. Mind-brain-body=same thing. There are around 100 billion neurons in every human. Each can synapse to up to 7000 other neurons. Because the hardware and the software are the same thing, you must constantly rewire the system to learn anything, to experience anything and remember it, to solve problems, to experience a worthwhile life. This happens at all ages.
We call this neuroplasticity.
How does this rewiring happen? We need to produce some key biological conditions. This is centered around production of Brain-derived Neurotropic Growth Factor (BDNF). BDNF is the protein which stimulates this rewiring.
I’m arguing that the conditions which support BDNF production are central to wellbeing.
You guessed it. Hormesis drives BNDF production.
How hormesis drives wellbeing
In the figure below, I have tried to simplify the basic logic behind a hormetic response driving neuroplasticity. What is involved (simply) to optimize the biology of rewiring is low insulin, higher insulin-like growth factor 1 (IGF-1), and absence of reactive oxygen species (ROS).
What is interesting is that a range of hormetic stimuli, sometimes through different mechanisms, achieve the same biochemistry The opposite is true when we expose ourselves to too much of the same stimulus. Once the stress response is maladaptive rather than hormetic, we produce insulin resistance, inflammation through ROS, and (sometimes) adverse levels of IGF-1 (see Figure below).
These ROS, insulin and IGF-1 do not always perfectly covary AND importantly they are also essential for humans one way or another for living. We need insulin, we need ROS, we need flexibility in IGF-1 production. It’s just that the systeM needs to have metabolic flexibility to respond and rebuild (especially the nervous system).
Bottom line: Neuroplasticity is essential for human wellbeing and the supporting biology may be the center of the mechanism for feeling good. There is no evidence that hormesis drives this biology.
So I’ve tried to put together a start to the broader framework of understanding how various exposures to environmental stressors are highly beneficial to us in hormetic (adaptable) doses and directly drive the BDNF and neuroplasticity mechanism and therefore well-being.
These are known mechanisms in the basic research.
Exercise is a great example of hormesis in action. This paper ” Impact of exercise on neuroplasticity-related proteins in spinal cord injured humans” showed a five-fold increase in BDNF in athletes after a 10 minute easy stint, but a decrease in BDNF after a marathon (42 km) event.
So exercise which we can easily accommodate and then adapt to drives the physiology of neuroplasticity and wellbeing. This is the hormetic response. The stimulus (exercise) eventually becomes toxic at high and more intense doses.
So my theory is that there is a straight biological and hormetic connection to wellbeing through neuroplasticity for several (and there are likely more than I have identified here) important health and lifestyle behaviors.
I’ll get to the indirect effect later in this piece.
Some factors, like psychological stress, simply drive adrenal axis responses which would be appropriate for an acute “fight or flight” short lifesaving sprint, but are entirely inappropriate and toxic applied chronically. Chronic psychological stress is known to drive reduced insulin sensitivity and increased ROS.
Others, like exercise, offers a balance. You need the stress, but too much is toxic. Sunlight exposure is like this. Some exposure drives Vitamin D production. There is good evidence to show the antioxidant (ROS defeating) effects of Vitamin D, as well as the vascular effects and increased insulin sensitivity through nitrate availability, but if you go and get sunburned then you will see the opposite effect.
Food is a really interesting stimulus. I think what we want is both the hormetic effect of the occasional fast, which is known to promote a catabolic (repair) effect and reduce ROS, IGF-1 increases, and low insulin. Obviously fasting for too long might have the opposite effect through probably high cortisol production. Equally, we need the anabolic effect of eating and the nutrients supplied by food. Too much food, especially junk processed carbs, bangs up insulin and ROS. So I think the intermittent fasting people are onto something when they cycle in and out of food availability.
Metabolic flexibility is an overriding theme here too.
By that I think that when you become metabolically dysfunctional and are constantly hyperinsulinemic and have high ROS, you really have the least effective system for neuroplasticity and cognitive rewiring.
Another factor is the health of your gut microbiome. Again, when not in its usual human supporting and symbiotic form, this is inflammatory. It helps create insulin resistance, ROS everywhere, and general metabolic dysfunction.
You’ll see below several ideas and mechanisms I propose. If you think of more then let me know.
Actually I just thought of another – brief ice baths. Short exposure-reduced ROS and increased insulin sensitivity. Too long=severe stress and probably increased ROS?
Indirect effects and wellbeing
Where positive psychology fits in here is something I have been thinking carefully about. I, along with others, have been into that field for a while now and we talk about creating social networks, being nice to others, giving your time and resources to others, and many other things. Have a look at our Sovereign NZ wellbeing index for the full meal deal.
So indeed these are important, but because many create the resources you need to buffer stress and control the exposure to the potentially toxic stimuli. Having a social network for example means you will less easily be overwhelmed by stress and more in control of your life.
A more distant indirect effect is money. Money by itself clearly has no direct effect on your BDNF, insulin, ROS and so forth. I’m pretty sure no one has done this study, but I predict that sitting and staring at a large pile of cash has very little effect on these!
But money gives you the resources. The time and space to create the networks, to give to others, and to control the exposures to the life stresses you want and thrive on.
Bottom line: Hormetic stress is the biological basis of wellbeing. We see good evidence across a range of environmental stressors how this all works. This brings the “Primal” type approach right into mainstream science where it belongs. I know the primal/paleo guys have been saying this for years, but we do need to convincingly bring the biology and the practice together which is what I’m trying to do.
This is a theory of stress, but in a controlled and balanced way.
I am critical of much of the work in public health, quite a bit of which I have done myself. We often try to understand how a single factor (e.g., exercise) is related to wellbeing. We assume a linear model where more is better and the dose applies across the population.
Clearly, in this hormetic, model that is just rubbish. Everyone can take a different amount of a particular stress (say exercise). What they can take and probably adapt to (hormesis) depends on:
Their exposure to exercise in their lifetime, weighted more heavily recently
The sum of all the other stressors they are currently being exposed to – obviously there’s less chance of adapting to an exercise session if you are sunburned and had a poor night’s sleep and an argument with your wife.
So what this all means is that what you need to optimize your potential at anytime is highly dynamic and different for you now than it was yesterday. And you almost certainly won’t resemble the same profile as others around you.
Last bottom line…
Moderation and stress that you can adapt to is crucial for well-being.
I’ve had three family dogs – all border collies. The one in the picture is Bluey, a 15 month old red/white border collie. He’s a friendly and active fellow, on a whole food meat and other stuff based diet.
I wanted the smartest, most active dog because my view was that they would need exercise and that would force me and the family to do more exercise. So is that likely to work, or is the dog more trouble than he’s worth and you just spend more money and can’t holiday when and where you like?
Well the original big dog in the research into dogs and physical activity was Prof Adrian Bauman and his dog Schroeder (a Jack Russell). Schroeder is the first dog I know to be a published author on a research paper.
There are now 29 studies looking at this, including one by me almost 10 years ago. I showed that dog ownership wasn’t enough; you needed to have at least a middle to big sized dog!
So what has the latest review shown? “Approximately 60% of dog owners walked their dog, with a median duration and frequency of 160 minutes/week and 4 walks/week.” Dog owners on average are slightly more active than non-dog owners, but the effects are small. We don’t know if giving someone a dog helps them be more active. In other words, we need dog intervention research!
So is it worth having a dog? Probably. There are numerous benefits, including some extra activity. Are there hassles? Damn straight there are. Mine crapped in the kitchen overnight and I was the one who got in trouble for it, and I even cleaned it up!
There’s something else about being out with a dog too. The sheer primal nature of it, the ability of the dog to draw you into the moment of being alive. Running on an empty beach. Chasing seagulls. It’s great fun.
How happy are you? How well are you doing in your life? How happy are New Zealanders, and how do they compare with other countries?
All big questions. You can find out how you compare with the average New Zealander of your age and sex here. You can access the Sovereign New Zealand Wellbeing Index here. You can view TVNZ’s Sunday episode aired on the topic here.
I am very proud to announce the public release of this Sovereign New Zealand Wellbeing Index. It’s the first survey point in a six-year research partnership with Sovereign . It’s also the first time anyone has tried to understand the epidemiology of wellbeing in a large (n=10,000) population representative sample in NZ. We will follow some of the same cohort across the six years. The basic logic is that if you want to improve the wellbeing of the population, then first you had better measure it, and generate some hypothesis forming associations.
We also used the same measures as used in the European Social Survey wellbeing module.
So this has been several months’ work for me, and even more work for my dedicated research team, as well as a team at Sovereign working on the comms side. Thanks everyone for the enormous amount of work.
Actually, that’s been the coolest thing about this project. The well developed comms and advocacy angle that Sovereign has been able to bring to the partnership. They’ve got an interest in reducing stress and increasing wellbeing straight out form a claims perspective as well as the corporate social responsibility angle
Frankly, we are very used to doing high quality research which mostly gets published in journals a few people read, and a few masters and PhD theses which even fewer (maybe even only a few!) people read.
So now, we have had a great link into releasing the report, advocating government and policy makers, getting TV and media coverage of the results and so forth.
Mostly, I’ve been blogging about nutrition, exercise, weight loss and chronic disease prevention and treatment research at the Human Potential Centre at AUT University. That’s where I am a Professor (Public Health) and the Director of this research centre. I will do a few more blogs in the wellbeing space to augment this report release.
Wellbeing is an area we are really getting into. We are trying to bring many of the principles of positive psychology into health. We also want to bring some of the principles of health, especially nutrition and exercise into positive psychology. Each discipline has lots to offer, but combined even more so.
These sorts of national accounts or indices of wellbeing have become popular in Europe recently and other less robust world-wide measures like the Happy Planet Index. To our knowledge, we are the first to do both mainstream health measures and wellbeing measures.
Sunday on TVNZ did a great job of presenting some of the results. Thanks TVNZ. See here.
You can go online and either take the entire survey and see what we measured, or just the “7-item flourishing scale” Goto www.mywellbeing.co.nz. We have the norms for your age and sex, so you can compare you results with those overall and of similar kiwis in the survey. Have a go its fun. Take the quiz.
Results for the Sovereign Wellbeing Index (This is the exec summary – get the full report here)
This report presents key findings from the Sovereign Wellbeing Index about the wellbeing of New Zealand adults in late 2012. The survey is the first national representation of how New Zealanders are faring on a personal and social level. The Sovereign Wellbeing Index provides a much needed look into how New Zealanders are coping within the economic conditions.
Wellbeing around New Zealand
Using flourishing as a measure of wellbeing there were small but consistent effects of gender, age and income. Older, female and wealthier New Zealanders on average showed higher flourishing scores. Similar findings were found across all other measures of wellbeing giving some confidence in the convergence of measures.
There were only small differences in average flourishing scores between ethnic groups (NZ European slightly higher than Asian) and regions across New Zealand.
Social position was a powerful indicator of wellbeing. Those higher on the social ladder reported much higher wellbeing.
The five Winning Ways to Wellbeing were all strongly associated with higher wellbeing. People who socially connected with others (Connect), gave time and resources to others (Give), were able to appreciate and take notice of things around them (Take notice), were learning new things in their life (Keep learning), and were physically active (Be Active) experienced higher levels of wellbeing.
We looked at the 25% of the population with the highest wellbeing scores and examined what factors defined this group from the rest of the population. This underpins the idea that psychological wealth and resources can be identified and public policy and action, and personal resources utilised to improve these determinants.
Similar findings to wellbeing in general were identified. Females were 1.4 times more likely to be in the super wellbeing group than males. More older, higher income, and higher social position New Zealanders were in the super wellbeing group.
Connecting, Giving, Taking notice, Keeping learning, and Being active were all strongly associated with super wellbeing.
Other health measures were also strongly associated with super wellbeing. These included better overall general health, non-smokers, exercisers and those with healthier diets and weights were all more likely to experience super wellbeing.
When compared with 22 European countries using the same population measures, New Zealand consistently ranks near the bottom of the ranking in both Personal and Social Wellbeing. New Zealand is well behind the Scandinavian countries that lead these measures.
New Zealand ranks 17th in Personal Wellbeing. Personal Wellbeing is made up of the measures of Emotional Wellbeing (rank 16th), Satisfying Life (rank 16th), Vitality (rank 16th), Resilience and Self- esteem (rank 19th), and Positive Functioning (rank 23rd).
New Zealanders did however rank above the mean for happiness, absence of negative feelings and enjoyment of life. However, we were still well below the top ranked countries.
New Zealand ranks 22nd in Social Wellbeing. Social Wellbeing is made up of the dimensions of Supportive Relations (rank 21st), Felt lonely (rank 20th), Meet socially (rank 21st), Trust and Belonging (rank 23rd), People in local area help one another (rank 21st), Treated with respect (rank 22nd), Feel close to people in local area (rank 23rd), and most people can be trusted (rank 11th).
Further exploration of our worst-ranked Social Wellbeing indicator ‘Feeling close to people in local area’ showed considerable variation across the country with the major cities scoring worst with Auckland at the top. Regional areas fared somewhat better. Younger people and NZ European New Zealanders scored lowest.
New Zealanders make choices everyday about their wellbeing. These are both personal choices as well as democratic choices about public policy and action at local and national levels. It is our vision that this index can help frame both personal choices and public policy and action in New Zealand. If it isn’t wellbeing for ourselves and others we are ultimately striving for, then what is it?
The Sovereign Wellbeing Index will continue to monitor the wellbeing of New Zealanders over the next four years. We plan to follow-up some of the participants in this nationally representative cohort to see how their wellbeing changes with time as well as continue to run this national index and benchmark indicators against European countries.
To sum up (that is, to skip the abstract and comments below and get straight to the next point), there is strong associational evidence that hard and prolonged endurance exercise may damage the heart, which results in sometimes serious heart problems. The overall risk is doubled compared to non-athletes, but the overall risk is still only around 2%.
Here’s the abstract of the study…
Aims We aimed to investigate the association of number of completed races and finishing time with risk of arrhythmias among participants of Vasaloppet, a 90 km cross-country skiing event.
Methods and results All the participants without cardiovascular disease who completed Vasaloppet during 1989–98 were followed through national registries until December 2005. Primary outcome was hospitalization for any arrhythmia and secondary outcomes were atrial fibrillation/flutter (AF), bradyarrhythmias, other supraventricular tachycardias (SVT), and ventricular tachycardia/ventricular fibrillation/cardiac arrest (VT/VF/CA). Among 52755 participants, 919 experienced arrhythmia during follow-up. Adjusting for age, education, and occupational status, those who completed the highest number of races during the period had higher risk of any arrhythmias [hazard ratio (HR)1.30; 95% CI 1.08–1.58; for ≥5 vs. 1 completed race], AF (HR 1.29; 95% CI 1.04–1.61), and bradyarrhythmias (HR 2.10; 95% CI 1.28–3.47). Those who had the fastest relative finishing time also had higher risk of any arrhythmias (HR 1.30; 95% CI 1.04–1.62; for 100–160% vs. >240% of winning time), AF (1.20; 95% CI 0.93–1.55), and bradyarrhythmias (HR 1.85; 95% CI 0.97–3.54). SVT or VT/VF/CA was not associated with finishing time or number of completed races.
Conclusions Among male participants of a 90 km cross-country skiing event, a faster finishing time and a high number of completed races were associated with higher risk of arrhythmias. This was mainly driven by a higher incidence of AF and bradyarrhythmias. No association with SVT or VT/VF/CA was found.
Dr Mandrola says the following:
It’s pretty simple: extreme endurance exercise, done over the long term and with great intensity, increases the risk of arrhythmia. There’s no refuting this strong association. These observations are both plausible and consistent with prior studies.
There should be no surprise when an endurance athlete shows up with atrial fibrillation or some other arrhythmia. We are not surprised when masters-aged athletes suffer from other inflammation-induced maladies, like overuse injuries, heart attacks, infections, and even divorce; why are we surprised they get AF?
But context is important. Previous studies have shown Vasaloppet finishers enjoy lower overall mortality. They smoke less, carry less body fat, and report better eating habits. This bolsters the idea that the lifestyle of endurance racing confers good overall health to most participants. Exercise is good. That observation remains unchanged and unchallenged. In the US, we would do better with an epidemic of over- rather than under-exercise.
It’s also important to emphasize that association is not causation. We don’t know whether excessive exercise alone caused the arrhythmia episodes. There are too many possible confounding variables to make a causation link.
[Grant – true, but see below, there is mounting evidence that it is exercise that causes this]
And . . . just because intense and long-term endurance exercise increases the risk of arrhythmia does not mean athletes should avoid a sport they love. These studies don’t tell us to recommend against endurance exercise. They simply inform both doctor and athlete of possible consequences. There are always trade-offs.
As physicians and teachers, knowledge of the association between chronic inflammation and disease might help us give better advice to our athletic patients. My guess, and it is just a guess, I am no coach, is that the same things that help an athlete avoid AF might also make them faster. Do you think getting adequate rest and recovery improves VO2max? Do you think being content with something less extreme than an Ironman or cross-country ski marathon might be antiarrhythmic? What’s wrong with a fast 10K?
[Grant – see below – I think its more about changing nutrition and training methods, but more work needs to be done]
2. Is it linked to the actual exercise or something else?
This is an important point because the study above is only correlational. However, there is enough mechanistic evidence developing to show that the actual exercise itself might be the cause. A study in forty endurance athletes showed significant signs of right ventricular damage following an endurance event lasting between 3 and 11 hours.
The authors conclude that “intense endurance exercise causes acute dysfunction of the RV, but not the LV. Although short-term recovery appears complete, chronic structural changes and reduced RV function are evident.”
3. What might you do to mitigate the risk, but still get the benefits of being fit?
Overall, I would say that these studies and the broader developing evidence shows that excessive and extreme endurance training increase your risk of heart problems. Like anything else, that’s a population measure. What it actually comes down to is whether it affects you or not. That’s binary, not probabilistic. You will either develop a heart problem or you will not.
So what do you do? If you, like me, like the exercise; you understand the benefits are many and done well outweigh the risk, I would say reconsider how you train. I wrote about this is in a previous blog on polarised training and fat adaptation. Both are likely to reduce the oxidative stress on the body and the time you spend in the prolonged hard cardio zone.
Remember, loads of oxidative stress, glycogen burning, and reactive oxygen species has numerous effects on the body; especially the immune system, tissue damage, and DNA damage. This results in a longer recovery time, more sickness, and higher risks of longer term problems.
Take home messages:
Exercise is still overwhelmingly good for you. We have a population epidemic of marathon sitting, not marathon running.
But…exercise taken to extreme might damage your heart, and you won’t know you have done damage until it’s too late.
New training and nutrition techniques may reduce the stress on the heart and body because you go slower more often, and only occasionally really fast (and probably get fitter), and you burn mostly fat (with your heart using ketones as a fuel which it prefers).
So, stop flogging yourself at training, eat less carbs – especially sugar, and eat more healthy fat. You might even be faster! You also certainly will be helathier.
Guest blogger Christian Thoma from the Physical Activity & Exercise Research Group and MoveLab, Newcastle University Medical School looks at how your state of mind affects your body when eating.
Christian makes a very important point in his email to me about this blog:
“Even though I work in a team which includes health psychologists, the behaviour around the act of eating rather than the choice of what to eat never enters the conversation. The same held true when I worked mostly with nutritionists.”
I absolutely agree with you Christian, this is a massive point….our state of mind is a critical factor.
Eating in the right state of mind
When it comes to food and health, it’s not all about how much we eat. It’s not all about what we eat. It isn’t all about the exercise/physical activity we do, or even how well we’ve been sleeping. As much as these things influence how our bodies process what we eat, there is at least one more factor that I think is underrated and under-researched. How we feel when we eat also matters. That we make poorer food choices when we eat in response to our emotions, or when we’re very hungry, probably isn’t very controversial. You can test it on yourself by observing what you eat, or feel like eating, the next time you’re upset or ravenous.
Food choices aside, the mental/emotional state you’re in when you eat matters, irrespective of your food choices. Have you ever been so stressed or upset that you were put right off eating? Or have such unhappy bowels that you find it hard to concentrate on anything else? Those are sobering illustrations of how much your mental state and your digestive system influence each other.
Extremes aside, does the state you’re in when you eat matter? I believe the answer is yes. It’s not my idea, it’s not a new idea, but it isn’t exactly given much air time. The question is why, and for a scientist like me — how? The physiology of stress and relaxation continue to be a hot topic of research, as does the process of digestion, but the two are seldom looked at together. This should be perplexing given that the extremes of the states we can be in are often referred to as rest and digest, and fight or flight.
Where we are along the spectrum of fight/flight vs. rest and digest is controlled by part of our nervous system known as the autonomic nervous system; think automatic, because it controls things that need to happen even when we aren’t concentrating on them, e.g. our breathing, heart rate, blood pressure, and digestion. The two sides of the autonomic nervous system, the sympathetic and parasympathetic systems, are in a constant tug of war pulling us between fight/flight, and rest and digest. Or put another way, between stress and a relaxation.
When our survival depends on fighting or fleeing, our sympathetic nervous system pulls hard to ensure our fuel stores, i.e. glucose and fat, are released from storage into the blood stream, and that this energy rich blood goes primarily to the muscles that need it. One key way it does this is by causing the release of the stress hormones cortisol, adrenaline and noradrenaline (epinephrine and norepinephrine for US readers). These hormones signal to the liver to make and release glucose, and the fat cells (adipose tissue) to release fat. Cortisol also directly interferes with the actions of the hormone insulin, which is responsible for controlling glucose and fat levels in the blood, and assisting protein in getting into cells, especially muscle.
The problem is many of us experience chronic stress. Stress from things we’re unlikely to either be able to fight or flee effectively. Stress not from physical danger, but traffic jams, financial worries, and relationship problems. As a result of this unresolved foundation of stress, our sympathetic nervous system dominates our bodies too much of the time. Being trapped in various degrees of fight/flight interferes with our digestion and metabolism of food.
Grant: In other words, the fight or flight system was really designed to go off quickly and for acute dangerous events. It’s likely that most of these events would be over with quickly (2 min?) AND we would have had to expend some energy dealing with whatever it was. In modern times, however, stress can activate the sympathetic nervous system for a much longer time, we call this chronic stress. Chronic stress is an issue because the physiology of acute stress in maintained for a long time. It’s unlikely this is a natural state for humans to be in, especially when we are sedentary and stressed.
Having cortisol and other stress hormones making sure our blood is already full of glucose and fat when we eat is not a good idea. It forces our bodies to deal with the fat and carbohydrates, and hence glucose, in the food we eat as well as that released from our stores. And insulin, the hormone in charge of the cleanup, is at a disadvantage because it has to contend with cortisol. In addition, blood is directed to the muscles, not the bowels, when we are stressed. That almost certainly doesn’t help digestion.
On the other hand, when we are relaxed and eat, our blood is directed to our bowel where it ensures our internal organs can do their work efficiently and make sure we get the greatest benefit from our food. When relaxed our blood glucose and fat are likely to be appropriately low in anticipation of the fresh supply from food. And, once nutrients from our food start entering our blood, insulin can do its job without contending with the opposing effects of stress hormones like cortisol.
So how do we achieve relaxation needed for good digestion and healthy metabolism? There are plenty of options to get some relaxation into our lives, but in the context of eating, the most obvious are: 1) take a little time to prepare food and really focus on the task of preparation while you do it; and 2) focus on the act of eating by minimising distractions, eating slowly and chewing thoroughly. The very act of eating can help put you into the more relaxed rest and digest state, if you give it half a chance. So, enjoy your food by taking time to savour the flavour.
Grant: This is really the idea of mindfulness. Its really powerful idea that we can achieve more wellbeing and a more fulfilled life by staying present. Eating is a perfect place to start practicing mindfulness. Just a quick check, I call it the Schofield keyboard test. If you are working on a computer, pick up the keyboard and turn it upside down and bang it hard on the desk. If stuff that was once food falls out, then there is evidence that you have been eating and working at the same time. That’s the opposite of mindful eating!
I’ve wanted to start a blog for quite some time now. The trick is to get the technical skills together well enough to actually know how to run one and do it regularly. Well, I’m just about there.
What will I blog about?
I am really interested in the science of how we can be the best we can be. This crosses disciplines such as biology, medicine, pubic health, and productivity management. The cornerstones are nutrition, exercise, sleep, neuroscience, psychology and well-being. I’ll be covering these topics under the broad heading of the Science of Human Potential (the name of this blog).
I’ve been interested in human health and performance for my whole career. I started in psychology then into sport and exercise psychology, then into public health especially physical activity then obesity.
There have been some twists and turns along the way which might help to give a view of why I do what I do and where it can go.
Sport and exercise has always been a massive part of my life. From an early age I played rugby union, learned to sail and race, and eventually ended up in the high school rowing squad. Rowing at my high school had no room for anything but high performance. So I was introduced to this at age 13. From there we won national championships most years. The combination of the sheer physicality of the sport and the team work and individual excellence required both mentally and physically really defined my teenage years and who I could become as an adult.
Being fit and involved in some sort of high performance activity has been part of my life since then.
I finished bachelors, Honors, and doctoral degrees in psychology at the University of Auckland by 1994. At the same time I had got into triathlon as a sport. I ended up racing semi-professionally. That’s code for “was never quite fast enough to earn a decent living, so had to supplement prize money income by working“. In the end I raced professionally in several world championships in long course triathlon, ironman and duathlon. That was great fun, and the skills and work ethic I have learned from triathlon are important to me.
The extra benefits from the high performance sport world, especially triathlo,n include:
I met my wife Louise because of triathlon. She ended up also as a professional triathlete, a better athlete than me. We’ve been married since 1995 and have three boys – Sam, Jackson and Daniel. Louise also started Vitality Works, a workplace health company acquired by Sanitarium in 2012. Vitality Works has allowed both of us to benefit from a huge amount of professional and personal development in health and well-being.
I figured out early that a high performance life is just as much work as a low performance life, so you may as well take the high performance life. It just requires a bit more work up front, but frankly you avoid work later and you get more choices.
I have the skills to stay fit and enjoy maximizing my biology for my own personal peak performance.
I still get to compete at a reasonable level in triathlon and running. This is cool because the age group triathlon and running groups are really fun, and you get to hang out with people of a similar performance, health, and happiness mindset.
My academic career began with part-time teaching in the Psychology Department at The University of Auckland during my PhD tenure. I moved to Australia (Central Queensland University in Rockhampton) and worked in the School of Psychology there for nearly 10 years. Most of our spare time then was dedicated to triathlon training and racing with Louise. I wasn’t going fast or far in the academic world at that point. Enter Kerry Mummery.
Kerry Mummery is now the Dean of Physical Education at the University of Alberta. He really mentored and started me on the journey to becoming a decent academic. We worked on several physical activity and health projects together. The most notable was 10,000 Steps. This started as a whole community project and morphed into a nationwide program which is still running successfully today.
This was the entrance into public health proper for me. I started at AUT in 2003 after the birth of Jackson our second son. Back in Auckland and into a new country with plenty to do. That’s when things really took off. I had the good fortune to have several great staff members and PhD students under my guidance. Almost all of these are still with me.
The highlights in the last decade are:
Working with dozens of talented doctoral and masters thesis students
Being highly successful in obtaining research grants and funding. This is the life of an academic and you live and die by this success. We are up over $20 million in funding.
A solid and respectable publication record. Ditto above. Important for gauging success. But by itself is unlikely to put much of a dent in the universe.
Being involved in Vitality Works. This has put a dent in the universe and allowed me to develop more formally into peak performance, well being and neuroscience.
Being the youngest full professor around for a while. That wore off as I aged!
Moving our work beyond physical activity into obesity, well-being, productivity, and nutrition/weight loss. Most recently the work we are starting in metabolic efficiency and weight is likely to put the biggest dent in the world.