Back in the days when we were cavemen, our brains were all about survival. It was hunt, gather, defend against predators, sleep, reproduce and repeat. Our brains thus developed taste and smell that didn’t like bitter foods as these often contained lots of mould and pathogens and that liked sweet tasting things, as these were the high carbohydrate and high energy foods that gave us the energy to depend, hunt and reproduce. Our brains evolved to give us a buzz of Dopamine and Serotonin neurotransmitter and neurohormones every time we ate a sugary food, and as Dopamine is the reward chemical, this made us repeat the behaviour and like sweet things. We also developed the “flight or fight” mechanism as defence against predators, with our brains giving us Adrenaline to run from stresses. For cavemen a stressor was a predators but also a lack of food or famine as famine meant death. The flight or fight process prioritised giving our muscles energy, and turned off all non-essential functions, like appetite. So our brains evolved to reward us when we ate and give us energy when we were stressed or in famine mode (see here). This was fantastic when a caveman, but has unfortunately locked underweight and overweight people in their weight states, making it incredibly hard for those obese to lose weight and those anorexic to gain weight, trapping them as food extremists.
It‘s not you, it‘s your caveman brainLaura Campbell
When underweight or anorexic, weight gain is surprisingly hard. Our body is in “famine mode” and as such pumps the Hypothalamus and Adrenal systems of our brain peripheral nervous system, with Adrenaline which in turn prioritises giving our muscles energy to make us go out of our “cave” (like our cavemen evolutionary ancestors) and hunt and gather food. Adrenaline also turns off all non-essential mechanisms like digestion and slows gastric emptying. However, in the process the reduced digestion also makes you less hungry. So you are incredibly thin but also incredibly hyper and full of energy and not hungry. You are also incredibly stressed as Adrenaline increases Cortisol the stress hormone. Stress switches your brain from rational “Prefrontal Cortex” logical brain to “Amygdala” anxious emotional brain which is more self-judgemental and self-critical and fixes you in black and white thinking (such as “good and bad foods”). This in turn makes you less likely to eat, more likely to be more rigid in what you do eat (often a restricted or controlled diet) and more likely to fidget restlessly and to exercise and so it is easier for a thin person to lose weight. Stress makes you also more likely to only desire “high glucose carbohydrate” quick energy foods which are often “low fat” and this reduces your body fat level further. There are nearly two times as many calories per gram from fat as carbohydrates so reducing fat can reduce calorie intake when underweight, and carbohydrates give you yet more energy to exercise and give you sugar lows, which make you more stressed. Exercise reduces Endorphins neurotransmitter which reduces Cortisol and Dopamine pleasure and reward neurotransmitter goes up when we reduce Cortisol, so we learn that exercising feels good and do it more. Exercise destresses and makes you happier and so you exercise more. Our brains also wire together stimulus and responses, so if you eat less when stressed our brains wire these two factors together and when you eat more, you feel stressed. Food becomes the stressor, and so you are more likely to have “food fears” and avoid certain foods (often the one’s we deem as “bad”). Sugars also make you happier as they give you Serotonin and so you are less likely to turn to food to comfort and more likely to feel excited and hopeful and be full of happy energy and do lots of things and yet more exercise.
As your weight goes down, you get hangry “hungry angry” which decreases your mood and this makes you less rational and locks you in a perpetual anxious-depressed-moody state where you feel less sociable and are less likely to have shared meals and so can more easily skip meals. To make things worse, when anorexic the metabolism slows down, and when you start eating more or try gaining weight, metabolism vastly increases as you get hypermetabolism and so burn off what you do eat fast. Oestrogen and Testosterone levels also decrease in underweight people (as you need sufficient body fat levels to make these endocrine sex hormones). Women need oestrogen to menstruate and so have no periods (and no period appetite and mood swings that make you hungry) and men need Testosterone to make muscle (which is why it is harder for underweight men to “bulk up”). Our brains conspire to lock us into extreme weights.
So when your thin friend says they can eat anything and never gain weight, they are probably right.Laura Campbell
However the reverse happens when you are overweight. At higher weights we have less energy and so are more tired. When we are more tired, we eat more and so get more tired as digestion takes a lot of energy. The more food we eat, the more tired we feel and so the more we eat. Our brains then give us Dopamine, the reward neurotransmitter and hormone from eating more, and so we get pleasure from eating more. The increased Dopamine increases Serotonin which makes us happier and so we learn food is happiness and we eat more, get more tired and sleep more and do less exercise as we haven’t got the energy for it. Exercise also, contrary to public belief, gives you energy as it increases Adrenaline and pumps blood around the body giving oxygen to the tissues and increasing respiration (the biological process that makes energy). So if you don’t exercise, you have less energy to exercise and so get stuck at a higher weight. To make matters worse, the tiredness and lack of energy and lack of Endorphin brain chemicals from exercise, make you more likely to get depressed and this lowers your energy more and increases your appetite more. Add to this the fluctuations in Oestrogen from menstruating and the effects of this on your Serotonin “happiness hormones” and you become even more depressed and more likely to reach for food for comfort. Comfort foods are often those high in fat and sugar as these give a “Dopamine buzz” and so you are more likely to over eat more.
The more you eat the more you have to eat as sugar and fat highs are addictive, and you need more and more of the stimulus to get the same response. Excess sugar causes mood fluctuations and is addictive with you needing higher doses of it to create the same pleasure level. This makes you more likely to overeat and have seconds and third helpings of meals. In turn this makes you more tired and if you sleep too much it disrupts your sleep cycle and so you are more likely to wake up in the middle of the night and have a midnight fridge raid. Poor sleep also increases carbohydrate craving and reduces emotional control. This lowers your mood further and so makes you more likely to turn to coping mechanisms such as alcohol which cause blood sugar unbalances, making you hungrier. Lack of sleep and alcohol also causes poor impulse control. Alcohol also affects our Hypothalamus of our brain, increasing appetite further. All in all, the fatter you are, the easier it is to get fatter and the harder it is to lose weight.
Food extremists therefore deserve our evolutionary empathy not our stigma and discrimination.Laura Campbell
Food extremists therefore deserve our evolutionary empathy not our stigma and discrimination. There should be no thin or fat shaming. Weight loss and weight gain is HARD. However, it is not impossible. We just have to rewire our brains (casually). This sounds very hard, and I know from experience it is far from easy, but I also know that is highly possible. If an incredibly average person like me can do it, so can you. The steps are as follows:
- A brain cannot be rewired if it is in stressed state. Do whatever you can to make your brain as “plastic” or “re-wireable” as possible (without using exercise if underweight and using as much exercise as possible if overweight). Whether this be through using meditation and self-care or whatever (see my other blog posts). Only when a brain is not stressed or anxious, can it produce the Brain Derived Growth Factor (BDGF) in order to grow and learn and change. Only in the absence of Cortisol stress hormone can the Hippocampus (the learning and memory centre of the brain), properly process complex information and change
- Get 7-8 hours sleep. The brain needs REM sleep to shift all the things it has learnt during the day from short term to long term memory. Like a memory stick storing complex info, we need to plug the stick into our brain computer and upload the information in deep REM sleep. We also need Non-REM or Slow-Wave-Sleep SWS, to recall the information and so it is essential we get at least 7 hours sleep a night to cycle between SWS and REM sleep and sleep deeply. A brain can only think rationally and logically and learn and remember after adequate sleep.
- Adapt your diet to your body condition, not what your brain is telling you. No matter what your appetite. No matter what you feel. Health is the absence of weight extremes. A healthy body is not anorexic or obese and so you must adapt your diet accordingly, no matter what you want. Fight a flaw in evolution, not yourself. Don’t use food as a weapon against yourself, but a cure. I know this is the dumbest thing to say, as it is SO HARD, but if you are underweight and your health is at risk, increase your nutritional intake. If you are overweight, decrease it. The way to do this is with mindfulness. This says “accept your body and its condition, no matter its history and how you are feeling” and “give me the knowledge to change the things I can change, the serenity to change the things you cannot change and the wisdom to know the difference.” Accept you cannot change thousands of years of evolution, but if you change your nutritional behaviour (which may mean eating when you are not hungry, not eating when you are hungry, not exercising when you have energy or exercising when you are tired or eating foods that stress you), you can change your brains. Our greatest asset is our health. Do what you can to get healthy and stay there. Lapses and relapses may happen, but with time, focus and determination, they will decrease and you can get there. I did. I was anorexic and I binged. I am a food extremist and I fought my own brain and rewired it. I fought the caveman and returned to a healthy modern woman. I got to healthy and I stayed healthy. If I can do it, so can you!
It’s time to take out the tool kit of healthy coping mechanisms, and do some brain re-wiring!Laura Campbell
Copyright Laura Campbell