Bodies are generally a pain; sometimes they are a pleasure.
They naturally get fat, lazy and addicted to all sorts of things.
In this article we’re going to explore the evolutionary reasons for addiction, especially as it relates to food. You’ll find out why some people get hooked easier than others, and what can be done about it.
Turns out it’s not just a problem of “will-power.” We actually are victims of our biology aided by the food industry, the lotto and many others—like pharmaceutical companies.
With the understanding of addiction you gain from this article, you’ll be able to see what’s going on. Then you can take steps towards living your life more in the way you want to live it.
We’ll look at some simple steps you can start taking right away to gain the ability to control your behavior towards things rather than have things control you.
When having fat was good—very, very good
As a High School Biology teacher I was sometimes asked about addiction and losing weight. There were parents wanting to quit smoking or wanting to help their overweight kids lose weight. There were students wanting to lose weight, or at least stop gaining.
I’ve seen wonderful, intelligent, obese, and anorexic people whose helplessness to change would break your heart. Food was making them miss out on life, and they knew it.
What were their bodies trying to do? Survive, that’s all, Darwin was right. Animal bodies evolved to survive based on the principle of seeking pleasure and avoiding pain. Over millions of years, organisms that over-ate and managed somehow to accumulate fat survived famines. The fat bought them more time in a famine or let them recover from something like food poisoning or a bitten hand .
Our metabolism is engineered so our bodies do amazing energy-saving things. Our bodies detect even a tiny drop in food consumption and it responds by slowing metabolism to burn fewer calories. Fat was hard to accumulate and valuable for passing along genes back then. This is why fat is zealously hoarded by our bodies now. Our bodies haven’t gotten the memos that starving is unlikely in a modern society and obesity is contra-survival.
While discussing overeating with students, I’d tap my head and say “blame the pleasure center in our brains and the recordings in our minds.” Our unwanted overeating behavior results from heavy duty genetic engineering wired into organisms over billions of years. Seeking pleasure and avoiding pain is an older mechanism than breathing air. It is a formidable force to be reckoned with.
Luckily, other genetic programming is in us for cool things such as enduring physical exertion and learning to like new foods by changing our taste receptors. We can run for miles and miles now because we used to do it to tire out the animals we were chasing for food. The game nowadays is to try and turn on the genetic programs best able to handle this bountiful environment, not the fat building programs.
Genetically we evolved to handle food in our environment long before Agriculture was invented a mere 11,000 years ago. Before agriculture we ate lots of different plants and animals. Only a few of the thousands of species we used to eat could be domesticated. Worse yet about 100 years ago we started heavily processing the few species we could raise. Processing concentrated the sugars and starches and added tasty molecules to them. Today about 70% of the American diet is processed food. We will explain later why it is addictive.
There is a movement of sorts of people breaking their processed food addiction. The new term for the cravings caused by processed food withdrawal is “toxic hunger”, coined by Dr. Joel Fuhrman. This is to point out the difference between eating to avoid withdrawal symptoms versus eating to satisfy “true” hunger.
Since the genetic package we’ve inherited has many programs, we must learn how to employ only the ones we want. We also have to learn how not to tickle our brains with addictive stuff (like sugar and flour). Lastly we get to learn how to keep our wonderful bodies toned. Let’s look at why that’s so hard.
Body, mind, spirit
It’s hard to stay away from addictive stuff and addictive behavior because it is baked into us as human beings. So let’s look at the components of the addiction problem starting with: what is a human being?
Let’s start with the Greeks’ oversimplified idea that man is a composite of a body, a mind and a spirit. Where one part starts and the others stop is hard to say.
The body is built by following genetic instructions developed over billions of years to survive in changing environments.
The mind is that wonderful invisible thing that evolved to store memories and use them in computing ways to keep the body alive as it encounters the environment.
Spirits are hard to define so let’s simply say they are you and I. Freud may have called it the “ego”. Whatever the term, it’s the entity directing the mind and body.
Our minds were made for survival things like remembering where the nearest watering hole was and where the predators likely were not. The mind did survival calculations like choosing a rock and shaping it into a spearhead to kill an animal. The mind holds memes (learned behaviors) and passes them to others like the body does genes.
The mind solves problems—it can’t help it. As we humans were evolving our wonderful mind’s job was for things like knowing our clan members (40-100 people) and the plants and animals in our immediate terrain.
These same minds allow us to live in modern times and handle vast quantities of complex data. We do this by using mind/body circuits so we don’t have to spend our attention on mechanical actions like tying our shoes or running. These circuits free up our attention to better handle our environment. We can then to things like look out for predators (or bad drivers).
An imperfect analogy for this body/mind/spirit would be airplane/autopilot/pilot. The pilot who is flying the plane is analogous to us moving our body. The mind, similar to the autopilot, acts like a computer using its recorded data and preset programs to respond to input coming in from the environment.
This analogy is simplified because if we hurt, endanger, or starve the body it will come to the forefront and do what it knows works for survival, like run and eat. Give our body the right stimuli, like the smell of cooked meat or baked bread, and it triggers the body to take over. Stimulate the body with potato chips and it will mindlessly eat them while we watch TV.
Stop the body from doing the pleasurable things it is used to doing and it feels bad, craves things or behavior and uses the mind to fix it. The good news is the body ultimately has to do what we want — if we want it bad enough, long enough. The bad news is that it is strong and stubborn.
The mind, like the body, can cause or trigger automatic behavior like eating or smoking. The mind has data about how much it likes which food and how to acquire it. Prehistorically it was something like where there were rabbits. Now our minds know where the McDonald’s are or that the Rocky Road ice cream is in the freezer. We automatically set up these circuits or habits about food continually.
We can consciously program our minds and bodies to do good things. Things like exercise, eating right and seeking happiness (from listening to music or talking with friends). Our minds amazingly can play both sides in the weight control game in that it seeks pleasure from junk food while making us exercise.
Food information comes to the forefront of our minds when environmental stimuli, like a Hershey’s chocolate bar, appear. The mind works on association. The memory banks have pleasure or “yuk” memories tied to certain taste memories. For example eating s’mores, turkey, ice cream, and on and on.
Advertising and branding work because of the association of the product to warm and fuzzy memories. Our minds seek pleasure and we will endure a lot to get it. Using junk food for pleasure can be replaced with well-prepared real food.
For example, simply using olive oil and Panko bread crumbs on cabbage, carrots, broccoli and cauliflower then baking them concentrates the sugars and softens them. The addition of salsa, hot sauce and other flavorful condiments gets the flavor up to a level that releases dopamine.
Yummy bean soups and hearty stews similarly get a lot of flavor into veggies. The key is having them prepared to your liking and waiting for consumption. Learning to like cooking is right up there with exercising for weight control for many.
The body—and its brain soup
The most important body organ in the overeating/addiction game is the brain. That addictive warm and fuzzy feeling is the result of our brain chemistry being “right.” Our brains and bodies were engineered molecule by molecule over millions of years for optimal survival. Brains have pleasure centers and euphoria molecules made for the purpose of having the organism repeat pro-survival behaviors like eating and sex.
One of the several euphoria molecules is dopamine, a brain neurotransmitter. A neurotransmitter is a molecule released by a nerve cell to send a signal to other nerve cells. Dopamine is released when a basic need such as hunger, thirst or sex is met.
The neurotransmitters, hormones etc. affect our emotions as well as our physiology. Emotions get us into motion, or in the case of extreme fear, freeze into no motion. The modern society we live in is being responded to emotionally as if we were still in the wilds of Africa.
The brain’s collective mix of neurotransmitters is sometimes referred to as a chemical “soup.” When the neuro-soup is rich in feel-good molecules, these molecules light up the pleasure center. The organism is being rewarded for the behavior they were doing.
When the soup is short on some ingredient, like dopamine, the organism craves things and feels bad. The organism uses its mind (data and computing power) to get the neurosoup right again. It does this by making the body do things that increase dopamine — like having sex, getting high, or eating -especially binging on salty, high energy, or fatty food.
Pleasurable acts, like eating and sex, are thus encouraged to be repeated over and over as they aid survival. Displeasure-able acts that generate fear or pain, like getting burned, are learned to be avoided.
This biochemical engineering arrangement came about in highly competitive wild environments. Over long spans of time, animals were continuously engineered to repeat behaviors that are useful for survival. Molecules like dopamine tells the animal they are on the right track.
Chemical shortcuts to fix the soup
Dopamine normally is released when a basic need such as sex, hunger or thirst is satisfied. Eating sugar, flour, fat, taking drugs like cocaine, or performing activities like gambling also releases dopamine. Exercise (about 20 minutes) also releases dopamine, and other molecules, stimulating the pleasure center of the brain.
Refined foods and drugs are modern means of taking a chemical shortcut to release dopamine. Modern society is geared to fulfill needs easily so provides loads of shortcuts with processed food, lotto tickets, drugs, prostitution, etc. This produces addicts of all sorts.
The need of these addicts to change their behavior supports about 14,500 addiction centers in the United States. Changing behavior is big business.
Other molecules that affect emotions and eating
Adrenaline, the fear molecule from the adrenal glands, evolved for extreme stressful situations such as fleeing or fighting a lion or fellow human. It makes us strong for a short time and shuts off the desire to eat. Adrenaline junkies in modern times get their fix from things like roller coasters, extreme sports, and risky behaviors such as crime and fast driving.
Cortisol, the stress hormone, also from the adrenal glands, will cause anxiety. Anxiety prehistorically could be elicited by things like the smell of a lion, the motion of a snake or a threat from a clansman. We evolved to be on edge and prepared for fighting or fleeing. Organizations like terrorists, politicians and news outlets know how to exploit this trait with threats and bad news to attract attention.
Cortisol causes cravings satisfied by eating fatty, sugary, high-energy food, and overeating in general. It also affects ghrelin, the hunger hormone. Meditation, exercise and social interactions help counter cortisol.
Depression occurs when we lack much dopamine, serotonin and oxytocin . Depression’s’ evolutionary value may have been extreme withdrawal until danger passes or submission after being bullied to prevent further attack.
So the bad news is emotions, positive or negative, can trigger overeating. The good news is exercise, meditation and social interactions blunt the effect of the emotion molecules that lead to overeating.
Between the feel-good and feel-bad molecules, we end up at some emotional state performing some behavior. Humans have found many ways to alter our emotional/mental state with food and drugs such as nicotine, caffeine or alcohol. We also use music, dance, literature and things like movies and mindless TV for this purpose.
Food companies have isolated the most addictive parts of our foods and concentrated those in processed food. It’s mainly flour, sugar and fats (oils) that light up our pleasure centers. Pulitzer prize-winning reporter Michael Moss explains this in his book, “Salt, Sugar, Fat. How the Food Companies Hooked Us.”
Why some get fat or hooked, and some don’t
All three components of us, body/mind/spirit, are unique. Except for identical twins, our bodies are genetically unique organisms. Our brains (and their soup) especially are different. Identical stimuli will be sensed differently by individuals and differing amounts of the various neurotransmitters will be released. The neurotransmitters and their receptors themselves differ between people.
An example of how we differ is seen with people that have lost some genes and have Prader-Willi Syndrome (PWS). PWS renders a person incapable of being satisfied from eating. Parents have to lock their refrigerators. PWS children have been found eating out of dumpsters.
Another example is the genetics of Native Americans and some Asians that make them susceptible to alcoholism. They have different forms of an enzyme that metabolizes alcohol.
We really do each have our own thing going on physically.
Additionally, each of our minds is a unique compilation of recorded events and teachings, each filed with their own emotional impact. These may include memories of eating comfort foods with our families. We may crave these foods when depressed to re-balance our brain soup.
Depressing, stressful memories may be triggered by the environment and the emotional response to these memories is often countered with overeating.
When it comes to our individual minds, we have to observe ourselves what triggers overeating. If we recognise what stresses us we can avoid those things and do activities other eating to alter our brain chemistry. Things such as exercise, movies, music or reading. We can cultivate hobbies to keep us away from triggers. A good hobby I suggest is researching food, nutrition and exercise.
Not only physically, but mentally we really do have our own thing going on.
Because of our unique bodies and minds, we all have different degrees of wanting chemical fixes. The resulting overeating and other addictions just naturally arose as modern society brought what we wanted easily within reach. We weren’t careful of what you wished for.
It’s a trap. Getting out and staying out
Being dropped into a modern culture offering addictive goodies for bodies evolved to crave and consume them seems wrong. It’s like dropping a mouse into a box containing a trap baited with cheese.
The mouse could not have possibly evolved for something as devious as a trap conceived by such a higher intelligence. Still, some mice do learn to avoid traps over time.
Thank goodness humans can learn to avoid the addictive goodies also.
Well, first by learning about the danger of being overweight and how some foods are addictive. We still have to eat and need good solid reasons to eat right. We have to decide to limit the convenient tasty processed food. We have to decide to exercise -at least a minimum amount. This learning of how it all works, the diet, the exercise, etc. is critical for getting our hearts and minds on board.
What can we do?
Whether it’s weight control or flying, man advances by doing research and running experiments. This process lets us obtain information, act on it to get more information to act on, over and over. We can use this “scientific method” to get more information and more control over our body weight. It’s not easy at first but it’s doable.
Weight control behavior is an interesting problem to research because so many unique things are interacting. The interacting factors include our personalities, our genes and our memories. These are in play in a given environment at a given time to give a unique emotional response and behavior for each of us.
This is why we individually have to experiment with diet and exercise to see how we respond physically and emotionally.The idea is to educate ourselves day-in, day-out about factors affecting body weight. A basic meal plan has to be chosen from the many available to start with. It has to be tried to be sure you can follow it.
The simplest solution, if it works, is to follow an established diet, like the Mediterranean diet, the Zone, etc. If you’re lucky you won’t have to reinvent the wheel—at least for a while. Either way established programs are a good place to start your research. Their information is laid out in a way most people can understand.
Let the Games Begin
Our game of life can have a subgame of “let’s live in a healthy body” in it. Games need obtainable goals so we need to set one for a given time. For example, a long term goal could be an acceptable weight of say 150 pounds. A short goal could be not to eat flour or sugar for a day and to see what happens.
If you obtain your goal, you win: if you don’t, you lose. What makes it a game is that the goal isn’t a sure thing—it will take some effort. Olympic medalists sometimes attribute their success to simply setting doable goals and making them over and over again. Writing them down seems to help.
So who are we playing against? The body and the mind of course. The body, with its fattening genetic programs. The mind, with its associative memories of food steering our food selection.
What do we play with? Again, the body and the mind. We can feed the body nutritious, delicious stuff so it’s not short on anything and craving. We can exercise the body to burn calories and release dopamine to get its brain “soup” right. The mind, we can give new data to use in feeding and exercising the body properly. It’s made to solve problems and needs data continually.
Strange game eh? We have to use the things that are acting against us to win. It’s like riding a headstrong horse, sometimes you’re in control, sometimes the horse is. It’s also like playing both sides of a game since we can influence our body and mind.
Where do we play this game? We play it in a constantly changing environment that is throwing stimuli at us. Stimuli that can instantly change our brain soup to crave something and emotionally motivate us to get it. This environment is also full of yummy immediately pleasurable bait that is not good for us in the long run.
Is it fair to have to play the game of life with an ancient body design in a modern society? Well, the mismatch of a body engineered for harsh environs in such a lush environment seems wrong—bordering on cruel. We are punished long term for doing what our body wants short term.
I used to tell my students “You are on the wrong planet for fair.”
This weight-control game would be impossible, even for adults, if not balanced with our massive brain capability and our capability for self- determination. It also helps having technology, like the internet, that enables us to load our minds with data supporting healthy lifestyles and endless recipes. We also can find support from others.
Imagination is probably the most important factor to win this weight-control game. Imagining new ways to prepare food and burn calories is key. It keeps the game fun, or at least tolerable.
Looking around at people it seems that their bodies are mostly winning. But, I think we just need education and practice in the care and feeding of bodies. In time we will set up memes and pass what works to the next generation—just like any other problem.
Food Addicts Anonymous (FAA) provides us with an example of a game plan.
The focus is on finding things that causes binges and by careful planning avoid them. Things like sugar, flour, wheat, overeating and undereating cause binges. Their mantra is:
Failure to Plan is Planning to Fail
Following the FAA’s Basic Food Plan for a while firmly establishes certainty in the mind and body when the next meal is coming and what it will be. This is reassuring to the parts of our minds and bodies that are made to seek out food.
Control is the name of the game for an addict. Losing control to a binge is a loss to be learned from. Like many addiction plans, they have a twelve step plan. They have meetings, sponsors and call on a higher power for strength. They take it one day at a time and make it work.
The food addicts anonymous people are an inspirational example that people do change their behaviors—once they decide to. They know it takes work and often help from others but they learn something every time they quit and finally break free. They quit and keep on quitting until they’re free.
So set a goal and make a game plan to get to your goal. You probably already have plans of some sort for both diet and exercise.
It may involve things like:
- Planning delicious nutritious meals that are tailored to satisfy without triggering a binge and eating them slowly. The good news is dopamine is released by palatability and satisfying nutrient needs—not just by salt, sugar and fat. Modern society not only gives us processed addictive food it gives us food from all over the planet, along with spices and recipes.There are simple plate plans like divide the plate into three sections and put lean protein on one, whole grains on one and fill the rest with fruits and vegetables.Our bodies adjust slowly, like in terms of weeks or months.Change one thing at a time in a logical order, for example, get rid of flour before sugar because it’s easier to add only sugar when craving.
- Having a certain amount of time between meals or snacks. The idea is to dribble in the right nutrients at the right time to prevent chemical imbalances and unplanned eating. It also puts rules in the game and so more certainty and control.
- Find exercises you like and will keep on doing, like walking. This maybe the single best way to stabilize our brain chemistry and prevent mood swings that cause binges.
- Knowing and avoiding what triggers a binge or mindless eating, like eating chips while watching a movie. Is a binge being triggered by being low on something in your diet,like calories, or trying to eat less of something like sugar? Is it because of an avoidable stress?
- Getting plenty of sleep. The less we sleep the more we eat.
- Make a list of things to research. It could be any possible thing that could affect your goal. Negative data helps. If you have a steep goal because you are in a dire situation, like diabetes, it may cause you to immediately change your behavior with little research.
Usually we change when we find what really communicates to us. This could be understanding the physiology of diabetes, heart disease and other threats like dementia, as they relate to being overweight. Once we are motivated, the health game begins in earnest.
All knowledge is not created equally
Research involves sifting out and ranking the important nuggets of information. I suggest keeping track of what you find out and where you found it.
It’s important to consider the source, some stuff is just ridiculous. Government sources, scientific papers, and established organizations should have more weight than opinion pieces. Statistics and references lend credibility.
The more sources and viewpoints you collect the more you will get a feel for what is true, important, and useful for you and your situation. Judgement will develop on how much knowledge is enough for a subject since you cannot go down every path.
What is important is seeing if the statements are true for you. Does eating spicy stuff or drinking more water really make a difference in your weight? Your mood? It’s easy enough to find out for yourself.
What to research?
The easy answer is everything. Clear up what is most confusing and important to you. Start simple and look up the words in the simplest source that lets you clear it up. There’s no sense in tackling something complex until you’re ready.
There are websites to help people understand research papers.
A good place to start is taste and nutrition, cover the basics like calories, proteins, carbs, fiber and fats. You may want to keep a list of things to research further as they come up while studying. Words like super foods, the glycemic index, reset points, and metabolic syndrome lead to many more.
You will quickly get into the most popular diets like: The Mediterranean Diet, Vegan diets, and the Atkins diet. The diets and reading materials of established organizations like Weight Watchers and Food Addicts Anonymous should be investigated early—it’s easy pickens.
The similarities between the diets especially should be noted. The things in common like eating fruits and vegetables are going to be what usually works. How do they handle addictive nutrients like salt, sugar and fat?
With knowledge we set good policy that let’s us gain control. The more knowledge, the more control-like learning to speak or to drive. Without nutritional knowledge, a mother fills a baby bottle with Pepsi. With knowledge comes confidence, understanding and control.
As we gather negative information, say about sugar and diabetes, it can dilute out the effect of warm and fuzzy memories about sugar. The solution to pollution is often dilution. If we look at the comfort food memories in our minds as the pollution, the data about diabetes, cancer, stroke, heart disease and dementia data would be the dilution.
It is similar to a smoker quitting after seeing lungs of smokers versus nonsmokers. It takes the fun out of it.
So research will help getting us off autopilot about foods associated with crazy good pleasurable memories. This is how people get off drugs like alcohol, the bad memories outweigh the good. Comfort foods do not come with hangovers so they have to be associated with being overweight and its consequences.
It may take a lot of repeating of the health risks of being overweight, like strokes, to make our behavior come down on the side of health. By continually tainting the pleasurable memories with an association with something bad, we hit a pain/pleasure tipping point. Our mind concludes it’s not worth it.
This is something like the alcoholic admitting “those days are over”—except it’s about a food or a quantity of food. It works the other way also. Good news about tasty healthy food makes them the new warm and fuzzy “go to” food. This is why research on food and exercise changes behavior.
What to experiment with?
It’s your game, do what you think will make a difference. Change one thing at a time for as long as it takes to make to be certain of the effect or lack of effect. It can be diet or exercise. There are worse things than trying new recipes and new sports.
Beside playing with the percentage of calories from carbs, protein and fats you can alter things like quantity of fiber and time between meals. You can alter exercise types and quantities. Your job is to learn what to do for the health of your mood, muscles, tendons, ligaments, bones etc. To set up and play your game you have to observe at least a little.
There are many variables in this game: do you want it to play it alone, in a gym, or with a buddy? Should you start taking the stairs, dancing, or walking? Should you try martial arts, lifting weights or bicycling? Do you want more flexibility from yoga? Will a treadmill set up with a TV, or a computer or with music actually be used?
Circuit breaking—circuit making
The purpose of all this research and experimentation is the reprograming of our mental and physical circuits -our behavior, our habits. We want to get off autopilot eating processed food and not moving enough. We want to get on autopilot eating fruits and vegetables and exercising. We want to do this so slowly that we do not ever give up for good.
The good news is our minds and bodies are infinitely programmable and reprogrammable so can be enlisted to get to a goal. The other good news is that in modern times we usually have the means, the time and money, so that we can afford to turn our attention to our health.
Two examples of useful information from research
1. Sugar: one of many biological traps
Let’s use sugar for an example of how some biological knowledge can help you tailor your body more to your liking. Sugar is such a simple product that is all around us we see little danger in it.
What does sugar have to do with hardening of the arteries, high cholesterol and diabetes? Well, our bodies have about 60,000 miles of blood vessels. Messing up the lining of them with sugar is not good. The lining is called the endothelium, and it is the largest secreting organ in the body. The endothelium controls things like blood pressure and inflammation.
Sugar and its by-products attach to proteins in the joints between the epithelial cells lining the arteries—similar to the way grout between tiles gets dirt attached to it. This opens the lining up and fatty deposits, called plaques, are formed.
Plaques cause strokes and heart attacks by narrowing arteries and by breaking loose and plugging up blood vessels. The lining is supposed to be nice and slick and flexible, if not, you’ll have high blood pressure—the silent killer.
So picturing sugar as wrecking the lining of your blood vessels changes everything. It also causes diabetes. But sugar (and flour) tickle our brains pleasure center so it isn’t easy to quit them.
Like nicotine, caffeine, sex, chocolate, drugs, etc., sugar is a “the more you have, the more you want” item. Flour and other starches quickly break into sugar—so eating white bread is like eating sugar, in fact it raises glucose levels faster.
Of course, “sola dosis facit venenum” or the dose makes the poison, which means too much of anything is bad. It’s just good to know that every sugary delicious bite or wonderfully refreshing high fructose corn syrup soda increases the biological pull of that substance on you.
2. Stress is serious stuff
Stress is another example of why being in a primitive body is a problem in a modern world. Similar to the way the brain’s pleasure center evolved for prehistoric environments, stress responses did also. The main stresses we evolved for were weather, hunger, and attack from other animals—including our fellow primates. Animals including Homo sapiens naturally stress each other with ruthless bullying to establish a food and mating hierarchy.
We are engineered to go berzerko in an instant. Responses had to be fast, a slow organism normally didn’t reproduce. Stress causes our bodies to dump stress hormones, like cortisol, into our bloodstream. This gets us primed for a fight or flight. Cortisol comes from the adrenal glands which sit like little hats on our kidneys.
Besides the immediate effect of increasing heart rate and blood pressure, cortisol suppresses our immune systems. Enough stress and we get sick and accumulate a type of belly fat that is hard to get rid of.
If we are stressed long term, we get digestive problems, insomnia, heart disease and other problems like depression. Nowadays the stress response could cause our early death—besides making life not fun.
So depression is caused by the stress response. How could that help us evolutionarily? Depression could keep the weaker, bullied animals from showing signs of aggression and so lessen attacks. This allows ranking to occur with less damage than the fights to the death.
Depression also causes animals to hole-up and not spend much energy—this aids survival in starvation conditions. This also limits exposure to others if diseases are doing the stressing.
In humans depression may allow for the analytical thinking out of a problem without distraction. There is a hypothesis that says psychic pain is similar to physical pain in keeping the organism away from something. For example, an organism learns not to bond strongly after the loss of friend.
Reducing stress by doing stuff
By far, exercise is the simplest, quickest, sure-fire way to handle stress. If we are moving our bodies, our bodies try less to get us to move with hormones.
Work or walk to physical exhaustion and see how much you feel like moving, even to eat, or how much you care what an idiot driver does. Stress hormones simply affect us less after exercise.
Finding a fulfilling hobby, being physically active, getting enough sleep and staying in touch with people that care about us reduces stress levels. In modern times this takes prioritizing our time.
In short, we are up against powerful genetic and mental forces that cause us to overeat. The replacement of our usual behaviors with new habits can be accomplished by setting reachable goals and planning. The more knowledge we have about diet and exercise the control we will have. By systematically researching and experimenting with our diets and exercise regimes we can get our bodies to do what we want.