What exactly are CDF's?
A stroll through a modern American supermarket reveals a cornucopia of products which, from an evolutionary standpoint, constitute brand new forms of food. These products have been manufactured very carefully to provide high levels of eating pleasure but are packed with sugar calories. Many of these foods do not taste sweet, which can be confusing to people whose work and education do not include an in-depth knowledge of food biochemistry. These foods are quite literally being tested on us, the consumers, and while an underfunded Food and Drug Administration (FDA) is doing its best to protect us, the food industry has been extremely successful in bringing to market hundreds of common items which have not been properly vetted for the long-term health and safety of consumers. In the context of two thousand millennia of human evolution, instant oatmeal, multigrain cereals, muffins, trail mix, and fruit juices are all brand new additions to our food supply. Marketed as healthy food options, these CDFs are in fact the occult drivers of illness. A Big Gulp did not exist one hundred years ago. Nor did cheese puffs, protein bars, or fast food restaurants selling bread made from genetically modified (GMO) wheat, meats from unhealthy animals treated with hormones and antibiotics, and drinks loaded with more sugar than humans for two million years might typically have consumed in a week.
Such products are exceedingly easy to mass produce and they yield high profits for BIg Food manufacturers. What makes it worse is that they are literally designed by food scientists to push pleasure buttons in our brains making them particularly enjoyable and even addicting to consumers. Big Food has heavily marketed CDFs, linking their consumption psychologically with celebration, fun, happiness, and family. What would a summer barbecue be without hot dogs, hamburgers, and soft drinks? What would a birthday party be without cake? For that matter, what would breakfast be without toast? At Thanksgiving we eat stuffing, mashed potatoes, sweetened cranberry sauce, and pies. We celebrate Easter with chocolates, Christmas with candy canes and gingerbread cookies, and passover with matzah. CDFs have been marketed as integral components of our national identity and our daily lives. One can chart the expansion of CDFs into the TAD alongside the incidence of obesity and chronic diseases and see a nearly perfect parallel. For two million years we lived on the Human Diet. Over the last 50-60 years that diet has been turned upside down, with minimal fiber and two-thirds or more of our calories coming from carbs. Since the introduction of CDFs as dietary staples, the United States has become the poster nation for obesity and chronic illness.
If we want to be healthy, we must learn to eat healthily, which means a return to the nutritional blueprint of the Human Diet. It means learning how to make smart choices amidst an ever-widening field of cheap, unhealthy options scientifically manufactured to hook us. It means learning how to think, budget, and shop a certain way. We must learn and adopt a strategy for how to eat mostly natural, whole foods that are high in fiber and nutrients and lower in carbs. These are the foods to which we are evolutionarily well-adapted. In broad nutritional terms, it means eating in a way that keeps our blood sugar relatively stable. This paper is about how to create good dietary habits that can be sustained for the long-term.
If you do not care to delve too deeply into the details of this publication, you may refer to the following nine rules and use them as a guide for creating your own healthy diet. As of the writing of this essay (October, 2015), the following represent the rules that I follow based upon my best assessment of the highest quality and most compelling and current research in the medical, nutrition, and basic science literature.
READ ON: The 9 Rules of Healthy Eating
Start from the beginning of this series of posts on Food and Nutrition
Humans have been evolving for about two million years (two thousand millennia). Our brains have grown in size and function, enabling us to survive ever more by our ability to plan and less by physical prowess. Our communities have been ravaged repeatedly by infectious diseases and our immune systems have evolved to defend us against millions of strains of potentially harmful microorganisms. And throughout these two thousand millennia of evolution humans have survived on a relatively consistent diet of leaves, stalks, and bark, berries from bushes, wild grasses (all sources of fiber), whatever animals we could kill (protein and fat), nuts and seeds (fat, protein, plus some fiber and carbohydrates), flowers, roots, and the occasional fruits and vegetables available during warm seasons (fiber and carbohydrates). During this protracted period, the human digestive tract evolved to accommodate to this diet, which was rich in antioxidants, high in fiber, moderate in protein, and relatively low in fat and sugar (carbs). I call this diet the Human Diet. Very carbohydrate-dense foods like tropical fruits and sugarcane were not part of the Human Diet (with the exception of tiny populations of peoples living near the equator) and did not make their way into wider consumption until very recently in the history of our species. Even grains such as wheat and rice, which, like tropical fruits, contain very high levels of carbohydrates, were not incorporated into the Human Diet until about 10,000 years ago–a short time from an evolutionary standpoint, and, as will be discussed below, those grains bore little resemblance to the ultra carb-dense, genetically modified versions which have come to dominate the commercial food market over the last 50-60 years. Perhaps the most important point I hope to make here is that for about two million years humans evolved alongside a diet that kept blood sugar relatively stable because our food did not contain carbohydrate dense substances like bran muffins, apple juice, and candy bars.
Evolution is an extremely slow and incremental process. It takes hundreds of generations for a species to adapt biologically to an environmental shift as radical as the recent changes in the typical American diet. The Human Diet to which we are evolutionarily adapted is the nutritional blueprint from which our bodies have learned to extract maximal nutrition and digest food with the least amount of stress. It is the diet that best enables us to develop properly, grow strong well-balanced immune systems, and live long healthy lives. The Human Diet offers us the best chance to avoid becoming obese and developing chronic diseases like hypertension, diabetes, and atherosclerosis which are now epidemic and quite literally ruining the health of our bodies and our economy.
In the last 50-60 years breakthroughs in the fields of biochemistry, engineering, and genetics have been applied to the manufacturing of fertilizers, insecticides, and crop breeding; this has utterly changed farming and has led to the introduction of new food substances into today’s typical American diet (TAD). Many of these new foods are fundamentally nutritionally different from those to which we are evolutionarily well-adapted. They contain proteins to which we have never been exposed, synthetic hormones, germicidal chemicals, and substances not found in anywhere in nature. Perhaps most pernicious of all, today’s food supply is dominated by carb-dense foods which cause blood sugar levels to soar. Research over the last 25-30 years has shown conclusively that consumption of carbohydrate dense foods (CDFs) provokes unprecedented escalations in blood sugar, and that these blood sugar spikes are responsible for the inflammatory changes that lead to obesity, illness, and drive the aging process. We now know that regular consumption of CDFs is the controllable behavior chiefly responsible for obesity and chronic diseases. The prevalence of CDFs in the TAD (typical American diet), more than any other single factor, is the cause of our current health and healthcare crises.
Read Part 3 of this series: Carbohydrate Dense Foods (CDF's)
Food consists of four categories of substance: protein, fat, carbohydrate, and fiber. All of our nutrients come from proteins, fats, and carbohydrates. Fiber supplies no nutrients, but is important to our health because it enables proper digestive and excretory functioning and enables healthy bacteria which live in our intestines to flourish.
Much disagreement has existed over the last few decades regarding what constitutes a healthy diet. The rules have changed dramatically in response to scientific research over the last few decades and my patients have a lot of questions. How many times a day should I eat? How much of my diet should come from carbohydrates? Which fats are healthy? How important is it to eat organic food? How many calories are safe to consume each day? What are GMO foods and are they safe to eat? Should I be avoiding gluten? How about red meat?
I will attempt to answer these and other questions in some detail below, but first let’s take a moment to lay out in very general terms what I have come to see as the basic idea behind a healthy diet.
Read Next Article in this series on Nutrition:Background Information Informing My Approach to Healthy Eating
As was described earlier, we now know that virtually all chronic diseases evolve into being gradually over time and are mediated through two primary mechanisms: increased inflammation, and diminished circulation. This is true whether we are talking about diabetes, stroke, heart attack, Alzheimer’s, hypertension, arthritis or any number of other diseases and disorders. We also now know that mood disorders are affected by blood flow and inflammation. Studies are showing that chronic depression and anxiety, as well as certain psychiatric illnesses such as ADHD (Attention Deficit Hyperactivity Disorder), and bipolar disorder, are directly linked to blood flow. We do not generally see these mood disorders without associated diminished brain circulation, (especially to the limbic and prefrontal areas) and, perhaps even more impressively, when we restore the brain’s circulation to normal we generally see reduction or elimination of the mood disorders.
Chronic use of drugs, including alcohol, caffeine, nicotine, and many prescription medicines, lead to diminished circulation and increased inflammation throughout the body, including to the brain. These substances are themselves to greater and lesser degrees mood-altering. Specifically, they tend to mask to some degree symptoms of anxiety and depression. Withdrawal from the chronic use of any mood altering drug involves a sharp adjustment to reality, a sudden awareness of feelings of anxiety and/or depression that had previously been soothed, masked, or numbed during chronic substance use. This is one of the reasons that substance users of all kinds, from coffee to cocaine, tend to share a common anxiety over the issue of quitting their mood-altering substance(s). Breaking the habit not only means giving up something from which they derive pleasure or respite, it also involves a painful process of experiencing often intense feelings of anxiety, frustration, irritability, and depression. The process activates the limbic system, which in turn stimulates the sympathetic division of the ANS to create a generalized stress response, including increased heart and respiratory rates, perspiration, and constriction of blood vessels causing diminished blood flow throughout the body, including the brain.
Although in time (usually after about 3 weeks) the body adapts to the substance-free state, and physiology gravitates toward normal function again, there often remains a lowered sense of mood, a feeling of something missing. For many people who chronically use a mood-altering substance of some kind, coming off that substance not only deprives them of their “high,” but also of a kind of ritual, something to look forward to. Taking a smoking break, sipping coffee while reading the morning paper, having that cocktail before dinner, or smoking pot before bedtime can become a emotional management tool as much for the ceremony of the practice itself as for the high derived from the substance. If some other practice is not substituted in its place, breaking even a soft addiction like coffee can be very difficult.
Man, it has been said, is a creature of habit. We learn to do things in a certain way, and by repeating our actions, we develop a sense of comfort and satisfaction in their doing. This is certainly true of behaviors, but it is equally true of thoughts and feelings. Since thoughts and feelings begin with brain activity in the prefrontal and
The front of the brain is comprised of the frontal cortex and the pre-frontal cortex. This is the central command area from which we do our thinking, generate ideas, initiate actions, build up (and exercise) our personal will. It is sometimes referred to as our ‘thinking brain.’ The pre-frontal cortex is larger in humans than in any other animal, comprising about 30% of our total brain mass, and this is primarily what distinguishes us as a species. The pre-frontal cortex in Chimpanzees, by comparison, makes up approximately 12% of their total brain mass, and in dogs it makes up approximately 5%.
Behind and deep to the pre-frontal cortex is an area called the cingulate gyrus. Shaped like the Nike ‘swoosh’ turned upside down, the cingulate gyrus is responsible for flexibility of mind, the ability to shift from one thought to the next, to make comparisons, to multi-task; to mentally shift gears, as it were. The cingulate is sometimes referred to as the ‘flexibility brain.’
Finally, deep to the cingulate gyrus lies the limbic system. As described above, this small, very deep area is the center of emotion. It is also the storage center for long term memory. Fear, love, reproductive drives, and the physiological processes that mediate those and many other emotional experiences are generated here. The limbic system is sometimes referred to as the ‘emotional brain.’
FMRI (functional magnetic resonance imaging) is providing new, fascinating data about the brain. FMRI measures blood flow. Since more blood is needed when we are actually using an area of the brain, blood flow is an indicator of brain activity. Because we have known for some time that different areas of the brain have different functions, there was a long held assumption that normal brain activity should show selective areas of activation and quiet at any given time. For example, it would make sense to predict that while your are doing math, the pre-frontal cortex, or ‘thinking brain,’ should be active, while the cingulate gyrus and limbic system should stay, relatively speaking, more quiet. Similarly, we might expect that while experiencing rage or fear, the ‘emotional brain’ would light up with activity while the ‘thinking’ and ‘flexibility brains’ would be dimmed.
In fact, FMRI has shown something very different. Rather than patterns of selective areas of activation and deactivation, what FMRI has shown is that healthy brains demonstrate a pattern of more generalized activation, with virtually the entire brain lighting up or quieting down as one functionally integrated organ. In a healthy brain, we may see slightly more or less activity in a particular area depending on what type of activity the brain is primarily engaged in at any given moment, but there is generalized activation of the pre-frontal, cingulate, and limbic areas whenever the brain is engaged to do anything! In healthy people, all three brains act together.
This is not to say that we never see selective areas of activation and deactivation. We do see it–too often in fact–just not in healthy brains. The brains of drug addicts, alcoholics, patients who have sustained brain injuries, patients with major depression, or other psychiatric conditions, show hot and cold spots, giving a ‘Swiss cheese” like appearance on FMRI. Even more interesting, is that patients with chronic pain but without any identified disease or history of injury show this same pattern, as do people who are under chronic stress.
The connection between the CNS and the ANS is extremely important to understand, not only because it explains the manner in which emotions are generated and experienced, but also because the stress response is conducted along the same pathways. For example, the famous “Fight or Flight Response,” starts in the brain as an activation of the limbic system during conditions of stress. Stressful situations activate the limbic system which in turn sends messages to the heart, skin, pupils, blood vessels, breathing muscles, and muscles in the jaws, neck, and upper back. When a stressor is sudden and strong the response is generally widespread and profound.
Imagine that you are alone at night in an empty parking garage when you notice a man lurking behind your car. Immediately, your heart begins to pound, your breathing quickens. You halt. Your body is telling you not to approach. “Can I help you?” you call out from a distance. The man stands taller and you can see that he is big with a menacing look on his face. “Can I help you?” he responds threateningly.
This situation happened to a patient of mine, a woman who is not generally a fearful person. She described how her heart felt like it was coming up through her throat. She turned and ran. Fortunately, she was not chased. She returned to her office where a co-worker called the police. After investigating the scene and finding no one, they walked her to her car. She drove home feeling sick to her stomach. She said that she felt her face flushed as though embarrassed and her heart rate did not calm down for the rest of the night. She had trouble getting to sleep that night and has subsequently developed a fear of parking garages which she experiences as a racy-queasy feeling in her stomach and chest.
Imagine that you strained your neck and upper back after being rear-ended at a stop light. Your car was damaged and, even though it was returned to you “fixed,” it continued to make a rubbing noise every time you turned the wheel fully to the left while moving–a sound that was not there before the accident. Your primary care doctor gave you some anti-inflammatory medicines and you were told the pain would go away as your muscles healed over the next 2-4 weeks. But the medicines bothered your stomach and the pain did not go away, in fact it got worse and you started to have difficulty sleeping as well since you could not seem to find a comfortable position for your neck. Returning to your doctor, you were given a prescription for muscle relaxants to help you sleep, and a you were referred to physical therapist. The medicine helped you sleep but made you feel extremely tired and groggy in the mornings so you stopped taking it. At physical therapy you were given ice and electrical stimulation therapies and taught stretches for your neck and shoulders. You thought that you were feeling a little better after the first week but on the second week you noticed an escalation of pain. Your P.T. increased your frequency of care from twice per week to three times per week. Unfortunately your busy work schedule made impossible for you to get away from the office that often, and your boss made a comment about your work product of the the previous few weeks since the accident. The P.T. explained that without more frequent treatment she would not be able to help you with the pain.
One month post-accident, you receive a call from the insurance claims adjuster who questions the need for ongoing care. He tells you that the accident was a minor fender-bender, that statistically you should not have even been injured, that even those who do get injured only require on average three sessions of P.T. to get well. He informs you that a lot of people try to run up big bills in the hope of getting a better final settlement, but that the insurance company’s policy was to pay for only a maximum of three sessions. He offers you $500 to settle your claim and informs you that you have forty eight hours to accept the offer or it will be withdrawn. You hang up the phone and your neck and shoulders are so tight that it feels the muscles might tear. You have a terrible headache.
This event, taken as a totality, gives us the experience of stress, and it takes place automatically, irrespective of logic or reason.
When a friend sneaks up behind us and yells, “Boo!,” the sudden surprise rings a loud alarm in the emotional brain, causing a massive discharge of neurons which then mediate the following event: the muscles in our shoulders and neck tense suddenly, our heart beats fast in our chest, and our breathing quickens. This generalized state of arousal is called the ‘startle response,’ and is the first stage of the famous ‘fight or flight’ response which is hardwired into our nervous systems at birth. The combination of the loud sound, the suddenness of its intrusion into our otherwise calm environment, and the unexpectedness of it, lead to our emotional brain’s automatic interpretation of the event as a perceived threat. Once we find out that no authentic threat exists, that we’ve merely been teased by a friend, the startle response, rather than blossoming into a full-on state of fight or flight, recedes, while other emotions begin to rise. We may feel our cheeks flush (vasodilation of the blood vessels in the face, consistent with the feeling of embarrassment), our stomachs, shoulders, and upper back tighten (tensing of the muscles consistent with feeling hurt or angry). These feelings come and go without our request or consent, serving the will of the emotional brain (limbic system), not the thinking brain (prefrontal cortex). Acting through the ANS, the emotional brain is half-responsible for one of the great dichotomies of human existence: how we think and how we feel do not necessarily agree and in complex societies may often run directly counter to one another.
There are five primary emotions: fear, anger, joy, sadness, and lust. There are many other emotions which are not considered to be primary emotions, and a primary emotion is not more intense or more important than any other emotion. The emotions are primary in the sense that all other emotions are either a variation of them (think of the numerous shades of a primary color) or consist of a mix of two or more primary emotions experienced simultaneously. For example, as mentioned above, anxiety and panic are lighter and darker shades, respectively, of the primary emotion fear. Similarly, frustration and rage are lighter and darker shades, respectively, of the primary emotion anger. Familial love, by contrast, is a mix of sympathy (which is a shade of sadness) and joy. And romantic love, the king of all emotions, is a cocktail of exuberance (a shade of joy), lust, longing (a shade of sadness), with just a dash of anxiety (a shade of fear) to keep things interesting. Part of what makes romantic love such a powerful experience is that involves the activation of so many (four out of the five) primary emotions all at the same time.
Some emotions are the product of physiological changes which take place in the chest cavity, some are primarily in the upper back, shoulders, neck, and jaws, some are primarily felt in the abdomen, and some emotions, like the startle response involve powerful physiological responses throughout the body. Variations of emotion are practically endless and, ultimately, are subjective. For the purposes of this blog, the point I am trying to make is that emotions are physiological changes which are attended by body sensations, and that these changes take place not as acts of reason or will, but automatically, unconsciously, from the parts of the brain collectively called the limbic system, and are carried out by the ANS which is not under conscious control. Emotions are much more about physiology than they are about psychology.
The Anatomy in a Nutshell
The human nervous system is divided into three parts: the CNS, or central nervous system, comprised of the brain and the spinal cord; the PNS, or peripheral nervous system, made up of all the nerves which leave the brain and spinal cord to supply the muscles (making them contract) and the skin (allowing us to feel); and the ANS, or autonomic nervous system, comprised of tiny spider web-like nerves that stimulate or sedate the activity of internal organs and wrap around blood vessels, enabling them to constrict and dilate. In this discussion, we will concern ourselves primarily with the ANS because it is the part of the nervous system which mediates the physiology of emotion and stress.
The ANS is not Conscious
Autonomic nerves are not under control of the conscious or thinking part of the brain (the cortex). That means you can’t will autonomic nerve activity. Instead, autonomic nerves carry out the directives of a part of the brain called the limbic system, a collection of evolutionarily primitive nuclei similar in function to the analogous parts of the brains of lower mammals like cats or dogs. The nuclei of the limbic system form the emotional part of the brain, enabling us to to have feelings, and are responsible for the phenomenon known as the ‘Fight-or-Flight’ response, which is the body’s way of reacting to stress. In stressful situations heart rate and breathing become more rapid, palms sweat, and muscles (especially in the back and neck) tense up in preparation for defending ourselves.
The stress response happens to our bodies automatically–whether we want it to or not. Constriction and dilation of blood vessels, speeding up and slowing down of heart rate, movement of food through our intestines, sweating, temperature regulation, and a host of other important physiological functions are controlled by the ANS, which carries out the orders of the emotional part of the brain, the limbic system, and none of these physiological changes are under volitional control. We can move, speak, and think through conscious intention, but we cannot change the physiology of our bodies in this way. We can control the way we behave while under stress but we cannot control how we feel in our bodies when our physiology changes during the stress response. You can act surprised (or scared, or happy, or brave, etc.) but you cannot make yourself feel or not feel the bodily sensations which accompany these emotions. It is often said that the heart wants what the heart wants, which is to say that our feelings, unlike our thoughts, are not changeable through debate or other rational processes.
The ANS Has a Brake and an Accelerator
The ANS is divided into two parts: the sympathetic division which speeds and tightens things up, and the parasympathetic division which relaxes and slows things down. In this way, the sympathetic division, usually referred to as the sympathetic nervous system or SNS is like the accelerator pedal of a car, while the parasympathetic division or PSNS acts a little like a brake.
It is commonly assumed that emotions are a function of thought, but that isn’t quite right. Let’s take fear as an example. Fear is an emotion which begins when nerve cells in the limbic system are aroused in response to some threatening stimulus. If a person has a fear of heights then riding in an elevator to the top of the Empire State Building is a stimulus that will arouse the limbic system to initiate the physiological responses we experience as feeling scared. Constriction of blood vessels in the gut (making the stomach feel sick or tight) and in our legs (making them feel weak and wobbly); increased cardiac and respiratory rates (making our hearts beat fast and our breathing rapid and shallow); activation of sweat glands (making our palms and underarms become moist), and dilation of the pupils of the eyes are all part of the fear response.
When our hearts start to pound, our palms become sweaty, our breathing becomes rapid, and our stomachs go tight or sick, that’s how we know that we are feeling scared. Sometimes when we are scared, we behave as though we are feeling excited, glad, angry, or nothing at all. How we choose to show our emotions is not always an accurate or complete revelation of our true feelings. Let us take a moment to consider the case of Mark, a patient of mine who reported that a co-worker of his was going through a particularly painful divorce. Mark felt sorry for his co-worker. But he also resented having to pick up the slack since she had stopped doing significant portions of her job. It had been several months and her lack of focus, frequent taking of sick days, and inability to complete vital tasks assigned to her was getting worse, not better. Mark felt trapped. On the one hand, he had sympathy for his colleague. On the other hand, he felt taken advantage of. He had personal problems of his own but did not bring them with him to the workplace. He feared confronting her as she seemed emotionally fragile to him and did not want to be labeled as uncaring. At the same time he resented coming in early, staying late, and using his weekends to do someone else’s work. He was trapped, emotionally speaking, in a state which we sometimes refer to as cognitive dissonance. Fear of hurting his emotoinally fragile colleague and looking bad in the eyes of coworkers was preventing his confronting her about her not doing her work; without confronter her he
Variations in the relative intensities of each of these physiological responses are what account for the varying shades of the primary emotion of fear that we all feel at certain times: anxiety, nervousness, panic, terror, etc. For example, if we start with fear, then decrease the heart and respiratory rates a little, while increasing the intensity of the stomach discomfort, we are now experiencing anxiety. If we start with anxiety and then strongly increase the cardiac and respiratory rates (tachycardia and hyperventilation) we are now experiencing panic. Prolonged panic can make us feel light-headed and may even cause us to pass out. This experience has been well described as what is known as a panic attack. Our bodies, through activation of the SNS by limbic system, create the physiological experiences we know as emotions. The variations of the fear response represents the body’s way of responding to specific types and levels of perceived threat.
Perhaps most interesting is the fact that we can experience an emotion (such as fear) without consciously registering that we are, in fact, afraid. Going back to the earlier example in the elevator, if the person with fear of heights rides to the top of the Empire State Building he may still be entirely unaware of the fact that he is afraid, even as his body is feeling strong fear-feelings in his chest, stomach, and legs. He may say to himself, “This is safe. A billion people have done this and no one has ever been injured. It is more dangerous to cross a busy street or drive a car than it is to go to the top of this building and I am not afraid of doing those other things, therefore, I am certainly not going to be afraid of this.” Though the logic of such thinking is hard to refute, emotions, quite famously, are not logical, and a person with fear of heights cannot avoid the physiology of fear: rapid breathing and heart rate, wobbly legs, sweating, dilation of the pupils. If he gets to the 110th floor and tries to walk out onto the observation deck, he may in fact experience a panic attack and faint. Knowing that we are safe does not mean that we are therefore not feeling scared.