A User’s Guide to the Human Body – Scarcity, Dieting, and Exercise

When it comes to addressing weight loss in the developed world, one of the great ironies is that even though people now have unprecedented access to fitness facilities and healthy foods, obesity is the number one health problem facing many of it citizens. What has changed in recent years that makes it so much easier for people to gain weight but simultaneously makes losing that so difficult? One of the basic beliefs behind this blog is that even though the world is changing at a breakneck pace, the human brain and body are basically the same as they’ve been since the species was still mastering the written world. With this in mind, today’s entry will be focusing on how some of the systems of the body work and how this can impact weight loss and how this information can be used to effectively and safely lose weight and keep it off.

Scarcity, or why the body is really good at surviving, but not so good at thriving

For the majority of humanity’s existence, life was a struggle. This struggle wasn’t about finding personal satisfaction or achieving goals, it was about not dying from an injury, finding enough to eat, and a safe place to sleep. As a result, the human body has developed amazing systems for staying alive long enough to make sure the next generation is able to survive and propagate. These systems in the body are designed to adapt to environmental changes with survival as the primary goal. It is only with the advent of modern transportation and the worldwide economy that the species has been freed from the cycles of feast and famine that had been a reality for so many previous centuries.

However, this relatively recent change to the world has only been in effect for a few generations. For many parts of the world, living for months without regular access to food due to war, drought, weather disruptions, or pestilence is still very much a reality. This is the world the body was designed for. As such, it has a remarkable ability to downshift its metabolism as needed. This isn’t a perfect process, but it is what has allowed the species to continue to exist in some of the harshest conditions imaginable. Systems in the body are designed to slow or shut down completely in times of need, so that whatever energy is available is dedicated to keeping the most vital systems working. It’s neither a pleasant nor fun experience, and it does take a toll on both mental and physical health over extended period of time, but it is part of what has allowed humanity to continue to this day.

What the body is not prepared for is the sheer amount of excess that it faces it in today’s developed world.  It is still prepared to do whatever it takes to keep the heart pumping and, as such, often reacts in ways that people would rather it didn’t. A large part of the problem is that while the body is programmed to deal with stress in a very specific way, it doesn’t have the ability to differentiate the different kinds of stress. So when stress levels start to rise, it falls back on old habits to deal with it. Unfortunately for most people, this means it switches back into survival mode – hoarding calories, staying in fight or flight mode, and basically making it easier to stay alive. The problem is that the sources of stress for the modern man or woman are not about a lack of hunting or foraging options or escaping from something that is trying to do him or her harm, it’s about traffic, childcare,  work, and a whole host of other more mundane issues. As far as our body is concerned, though, these latter examples are perceived as just as life-threatening as the former, and it will react to the the same way.  The fact that these stressors can’t be rectified by stumbling across a deer or field of greens isn’t factored in. When it comes to losing and maintaining weight, this can be a major obstacle.

Let’s talk about food

The body requires a pretty complex mixture of nutrients in order to maintain optimum health. Categories like fats, carbohydrates, proteins, minerals, and vitamins only give a partial idea of how varied the raw materials needed to keep the body fueled and maintained are. Each category often contains several subcategories based on the composition of the nutrients involved, how the body breaks them down, and what the body does with those components once they are broken down.

A good example of this is carbohydrates. Refined sugar, Russet potatoes, and sweet potatoes are all examples of carbohydrates, but each one is dealt with differently by the body, and as such, they have different effects on the system. Refined sugar breaks down most easily into fructose, but also converts more quickly to fat. Russet potatoes are more complex, but they also break down easily into sugar and therefore fat, but the slightly slower digestion and higher fiber composition means that the energy they provide will last longer. Sweet potatoes have a comparatively high fiber content as well as numerous vitamins and minerals, making them a more complete meal, but the longer digestion time means that it takes longer for satiation to set in and the calories to become available.

By understanding this, it’s possible to pick a diet based more on what’s needed versus what’s craved. But each system of the body is different, and because of this, it’s necessary to understand why certain systems may crave one food over another, and why this information so often transforms cravings from what is needed to what is wanted, and why there may not be much conscious influence over these decisions.

Eating good, dieting bad

Before examining some of the major systems in the body and why they crave what they do, it’s important to mention why limiting food intake in order to lose weight is never a good idea. For the medical community, the word diet simply refers to what makes up a person’s normal food consumption. If the diet remains relatively stable, then the body will accept that as a baseline and adjust the metabolism accordingly. Unfortunately, this also means that if the caloric consumption suddenly decreases, then the body will assume it is in a time of scarcity and will downshift to accommodate this change. The problem is that every time this happens, the body makes the shift faster and faster. So while the first decrease in intake will lead to rapid weight loss, each subsequent attempt will have less and less impact. Even more unfortunately, when the calories are re-introduced, the body will assume that the next round of scarcity is coming soon, and it will be even less willing to surrender its precious stores of fat, in case they are needed. For the individual, this means that not only to successive attempts yield less results, but also the amount of weight gained afterwards will increase each time.

Sugar-coated brains

The seat of conscious thought, the brain, is a sugar junkie. It is said that humanity didn’t start making large jumps in developing culture and society until it started cooking its food. What does one have to do with the other? When food is cooked, it is broken down. That means that there is less work for the body in order to get the nutrients from the substance being consumed. One of the big nutrients that’s released is carbohydrates, which are broken down into sugars of several different types. The one most related to weight gain, fructose, is a favorite of the sweet-toothed cerebellum.  So as the brain was starting to get access to a more accessible source of what it craved, it had more energy for things like contemplating and creating. Unfortunately for the human race, the brain also interprets the signals of the body in order to let people know what it wants. This means that whenever hunger does strike, the brain’s first impulse is to take care of itself first, so it sends the body looking for the nearest available source of sugar. In previous times, the scarcity of easily available sugars helped control this impulse, and even then, the sugar containing foods often contained other ingredients that triggered the satiation response, allowing the body to tell the brain “enough”.

In modern times, the situation has changed. Foods with a high fructose content are everywhere and the body has little ability to respond when it is in such concentrated amounts.  As such, when hunger pains strike, the first impulse is often to reach for an easily accessible source of sugar as opposed to something more complex.  This is because the brain, while smart in its own way, is fairly selfish. It sees the body primarily as a device that allows the brain to interact with the world, and so when the caloric level gets low, it’s primary goal is to feed itself and to get the body to just be quiet. When sugars are used to achieve this, the body does get some nutritional benefit, but it also receives a load of endorphins from the brain which act to sedate it, giving the brain what it wants. Unfortunately, the amount of carbohydrates are usually in excess of what the brain needs and while the body makes use of some of them, a lot is simply turned into fat, which is also necessary but not enough to keep the body functional.

The other issue is that when the body does use carbohydrates, it uses them for quick bursts of activity. If these calories aren’t consumed fairly quickly, then the amount converted to fat increases. Since most people have rather sedentary jobs which require more of the brain than the body, the craving for carbs increases while the need for them decreases. This combined with the easy access to them leads to an increased amount of simple carbohydrates being consumed with less being burned, over time contributing to an expanding waistline.

Make a friend of fat

So why does the body convert those excess carbs to fat anyway? The reason is that there is one organ that brain can’t do without and that is the heart. The brain needs a steady flow of blood to do its thing and the heart in the engine that keeps that blood pumping. And what is the heart’s preferred fuel source? That’s right, fat.

Unfortunately, the body has a much harder time converting stored fat to fuel than it does with foods that are naturally high in fats. These natural fats are often rich in essential nutrients that are both increase the ability of the body to use them as well as offer other benefits such as anti-inflammatory benefits. In their absence, the body will use stored fat, but as mentioned above, it does so much more reluctantly because with a lack of fat in the diet, the body will look at is a scarce resource and will hoard accordingly.  Unfortunately, over time, this will cause fats to gather around the organs that use them, decreasing their efficiency, include their ability to use those fats.

The liver is one of these organs and one of the substances it converts fats into is hormones, including testosterone and estrogen. This can cause a host of infirmities including fatigue, depression, and a lack of hormonal regulation, which carries its own series of discomforting side effects. Fats in the diet also transport essential vitamins which maintain healthy hair, nails, and skin, so a lack of fat in the daily diet will often lead to these structures becoming weakened and fragile. Modern dietary advice has begun to move away from the zero fat approach it took in the seventies and eighties, but the demonization of fat in the diet has led many to cut fats as part of their weight loss efforts, which can cause more harm than good.

Finally, fats are an incredibly concentrated source of energy (one of the reasons why the heart values them so highly). Regular fat intake will often decrease cravings as they increase the amount of satiation and provide fuel which is far more efficient for long-term energy than carbohydrates. This has the effect of increasing satiation and decreases the amount of food needed to achieve that state.

Protein-powered muscles

When a person goes on the traditional “diet” as espoused by common sense, they often end up eating less meat because of its fat content, but in doing so, he or she is causing more harm than good. Protein is essential to the maintenance of the muscles of the human body. Every time the muscles are engaged, small tears are formed in those tissues. Protein is needed to repair these muscles, and if it’s not present in the diet, the body will cannibalize existing muscles for that protein. This not includes the obvious muscles that are used for movement, activity, and posture, but also the internal muscles needed for the organs to function (examples of this are the ones that inflate and deflate the lungs or which move food though the digestive organs). That means that in the absence of protein in the diet, muscle tissue will be consumed regardless of what other foods are being consumed.  Muscles also burn carbohydrates, so the less muscle there is in the body, the less carbohydrates are being consumed, which means more of them are converted to fat. The net effect of this is an increase in fatty tissue with a decrease in muscle, which is often exactly opposite of the reasons presented for reducing caloric intake in the first place.

Proteins are also one of the most satisfying foods for the body to consume, so a lack of protein in the diet often leads to an increase in the consumption of carbs in order to reach satiation. This furthers the accumulation of fat while simultaneously lowering energy levels.

Diet soda is a sucker’s game

So now that some basics about nutrition have been laid out, it is time to look at one of the biggest lies of the modern food age. Diet soda (and all diet foods in general) are based on the idea of “guilt-free” eating. These chemical concoctions are often made using artificial ingredients which fool both the tongue and the body into thinking it has eaten something decadent without actually containing calories. It sounds like a good idea, but as mentioned in the opening section, the body is sometimes a little too stupid for its own good. As far as the body is concerned, if something looks like food and tastes like food, then it is food. So when that zero-calorie snack hits the stomach and is revealed to have the nutritional value of styrofoam, the body assumes it is in fact starving and will go into survival mode. This means that the net effect of all those snacks and beverages is that when real food is consumed, more of the calories that are contained will be stored as fat than would be otherwise. If the food is sweet in flavor, then the effect is even worse, because the body will start to treat all sweets as suspect and will hoard more carbohydrates as a result, quickly increasing the amount which are converted to fats.

Why eating “fake” food = weight gain

Not all “fake” foods are “diet” foods, but the effect is similar. Foods that are designed to have an unnatural shelf life and yet still be tasty often do so by sacrificing much of what makes them worth eating in the first place. Often the ingredients which keep these foods from rotting on the shelf keep them from being broken down inside the body.  Much like a starving animal will eat rocks just to have something inside its tummy, “fake” foods will give trigger the stretch receptors in the stomach, giving the illusion of satiation, but when broken down are mostly empty fat and carbs. This leads to an increase in both appetite and malnutrition. Another complication of these foods is that their inability to be broken down often causes them to sit in the gut, which disturbs the natural gut bacteria, decreasing the body’s ability to break down the next meal.

Mom sets the starting pace

Speaking of things growing inside the gut, one of the most important developmental periods for the metabolism is during gestation. A mother’s diet during pregnancy can have an important impact on the child growing within. If the mother is adequately nourished with a wide variety of nutrients in the diet, then the child will be born with a metabolism that is set to consume calories as they are taken in. However, if the child is born into a world where nutrients are less available, that child will have a slower metabolism and be more able to deal with the scarcity that such a lack of nutritious food would suggest. In places where food availability is low, this is a smart adaptation, but if the mother is eating high calorie foods with little nutritional value, that child will instead be more at risk to develop problems like obesity, as his or her metabolism is preset to hoard calories, even if they are readily available.

Another factor in this is that, since the mother’s womb is the first environment the child is exposed to, whatever bacteria are in the mother’s body will be considered by the child’s body to be the most natural. In the case of gut bacteria, this means that the natural flora of the mother’s gut will be passed on to the child and those bacteria will be considered to be the most “preferable” over at least the first seven years of the child’s life. If the mother has a varied and healthy diet, the child will be able to deal with foods more efficiently than a child whose mother’s natural flora are more limited.

Not everyone can eat everything

To continue with this idea of inherited dietary strengths and weaknesses, every persons internal chemistry is a little different. Depending on the environment both inside the womb and during childhood, exposures to different types of foods can cause different reactions. Both the blood-type diet and the Mediterranean diet make use of this idea. The basic concept is that where in the world an individual’s family line developed, that individual will generally be better suited to digest the traditional meals of that place. For example, the consumption of dairy foods from cows was established in the West long before it was common in the East. This can be used to explain why people of Asian descent are more likely to suffer lactose intolerance than those of European descent. This also means that if a person eats foods that are more traditionally consumed by their ethnicity, that individual’s body will be able to more effectively break them down and make use of them.

The cake is not a lie

Now it’s time for some good news. Yes, that diet soda and the 100 calories snack packs need to be chucked in the trash, but that just means there’s more room for homemade cookies. Deserts are often referred to as decadent, but what that really means is that shouldn’t be consumed all the time. However, if a person has a craving for that after dinner cookie or brownie, go ahead and have one. Just make sure it’s a good one, full of fat and sugar and made from scratch. The problem with store bought deserts is that they are usually so full of filler that they really don’t satisfy. It’s far better for both body and mind to eat a real piece of cake, and over time, the real satisfaction from it will quell the cravings that are only mildly subdued by the latest Nabisco product.

Don’t go to dinner angry/Perception is everything

As has been mentioned throughout this article, the body often determines its dietary needs based on how it perceives the world. When there are no worries about personal safety, food availability, and shelter, stress remains low and the body has no fear of entering a survival phase, so it keeps the metabolism appropriate to daily activity levels. However, if the world feels dark and every decision has the specter of life and death lurking around the corners, then the body will hoard every calorie available for what it sees as inevitable time where fight or flight becomes necessary.  If the danger is real, then weight loss becomes a more minor concern, but for most people, especially in the States, this danger is mostly imaginary, fueled as much by the media and anxiety as any real potential threats.

Also, this increased stress raises cortisol levels in the body, which among other effects, increases sugar cravings while also increasing the amount of fat that gathers at the abdomen (the least healthy place to carry excess weight).  Also, the heightened alertness and higher sugar intake tend to interfere with sleep, making it harder for the body to return to a relaxed state and increasing the stress placed on the body’s systems.  For a small population, dealing with this anxiety requires medical intervention, but for the majority of the population, the same healthy habits that lend themselves to weight loss will also lower stress and anxiety levels. If the predominant complication in achieving this calmness is an overactive mind, counseling might also be helpful, as there is a strong correlation between stress eating and underlying concerns that talking can help allay. For people who need a more physical outlet, however, there is one great option that is cheap, doesn’t require expensive equipment, or access to a gym.

Think I’ll go for a walk outside

Walking is one of the best forms of exercise for a simple reason: it’s what humans have been doing for the majority of their existence. The use of vehicles as a method of transporting people is a relatively recent development. For most people throughout time, walking was simply the only option for getting from here to there and back again and their bodies reflect that. The muscles used in walking assist in a variety of internal functions including circulation, digestion, and immunity. As the muscles of the legs contract and relax, they move blood and lymph from the lower extremities back towards the core. With each rotation of the trunk, the muscles of the abdomen assist the intestines in breaking down food and transporting it through the digestive system. Each movement helps the body in very subtle ways, and because walking is low impact and low intensity, it is a form of exercise that can be kept up for long periods of time without creating too much fatigue. This allows a person to engage in prolonged aerobic activity while not leaving him or her so exhausted that other aspects of their life become neglected. For people whose injuries prevent walking, bicycling is another wonderful, if more limited option.

These forms of exercise also have the benefit of lowering stress levels, which reduces cortisol levels and increases the body’s ability to rest when appropriate.

Breathing is fundamental

One of the reason that the exercises above were chosen is because they manage to be aerobic without being too strenuous. Most of the systems of the body use oxygen as a necessary ingredient in normal function and a lack of it can cause those systems to function less efficiently. The creation of energy that the body can use takes two forms: aerobic and anaerobic. Aerobic reactions require oxygen, anaerobic exercises do not. The reason aerobic reactions are preferred in weight loss is that they create far more energy than their anaerobic cousins. In practical terms, this means that less calories are required for these activities, and as mentioned above, the body is far more stingy with its stored calories when it feels the supply of these is in jeopardy.  For that reason, engaging in aerobic activities creates far less hunger in relation to calories burned than anaerobic exercises. They also put far, far less strain on the circulatory system as they don’t raise heart rate and blood pressure to the same level. Finally, the higher levels of oxygen in the body increase the consumption of stored fat, as the body doesn’t feel as stressed and is more willing to part with it. “Burning fat” is indeed an appropriate description of exercises of this type, both for the increase in metabolism and heat as well as the necessity of oxygen in the equation.

Huffing and puffing towards failure

Speaking of anaerobic exercises, the first warning sign that a person has shifted into an anaerobic mode is a shortness of breath. This means that there is inadequate oxygen in the body to maintain aerobic levels of activity and so the body has shifted to a less consumptive form of energy creation. This has the effect of raising stress levels as well as blood pressure and damage to the muscles. While this is the preferred method for building strength, it has less benefit in terms of burning fat and calories. For the body, this is seen as just another stressor, and while it can be very useful in terms of training, if this is the only type of activity engaged in, than weight loss becomes secondary to strength building and often the body will actually retain more fat over the long term.

While the above description might seem to apply to activities like weight lifting, it actually applies to any activity where breathing becomes labored. Another sign that oxygen levels are low is profuse sweating, so if that hour long workout on the Stairmaster leaves a person drenched and panting, the amount of actual weight loss resulting from it might be less than expected.

Build endurance, not bulk

One of the reasons why people try to lose weight is vanity (which is perfectly reasonable), but because of this, there is often too much of a focus on building pretty muscles over useful muscles. Useful muscles are the ones that are used every day where as the pretty muscles often serve little purpose for people who jobs are less physically strenuous. The downside of overworking those less useful muscles is that they require constant maintenance in terms of both food intake and physical activity, not to mention that they are heavy, requiring more energy just to support them. They also have the unfortunate tendency to get flabby once the workouts stop.
Useful muscles, in comparison, are often leaner and burn more calories on a day to day basis without dramatically increasing appetite which does more to benefit the metabolism. They also decrease fatigue by being better able to maintain posture while not overtly increasing the overall mass. A useful example of this is swimmers and dancers who have an amazing strength mass ration without losing a significant amount of flexibility or range of motion.

Reaching for comfort

But why are flexibility and range of motion important? Because once a muscle becomes tight, it often compresses other nearby structures, reducing the body’s ability to function efficiently. This creates stress, which has already been gone over, as well as increasing discomfort, discouraging exercise and encouraging being sedentary.  Especially in the beginning of an exercise program, this can be disheartening enough to stop progress and, as hinted at previously, when undertaking a lifestyle change like this, it is important to not progress in starts and fits, as that will just encourage the body to go into survival mode as opposed to seeing this as a more permanent and less stressful change.  Also, stretching can be very relaxing and an excellent way to come down at the end of a workout. Just remember that if breathing becomes strained, back off and relax.

Take a break for success

Backing off and relaxing a little is actually good advice for any form of physical activity. As mentioned previously, the most effective form of exercise for weight loss is aerobic, which require plenty of oxygen. If at anytime during a workout, breathing becomes labored, ease back on the intensity.  If the shortness of breath returns quickly, then take a longer break before trying again. One of the advantages of doing less intense activity more often is that it rarely requires a shower after every workout. With that in mind, a person should try to do as much as they can comfortably throughout the day, but with the knowledge that he or she can quit if it gets to be too much. Leaving that escape hatch open often reduces stress and people who know they don’t have to kill themselves every workout are much more likely to make it a permanent part of their life.

Water, water, water

To wrap this up, a reminder that water is still the best liquid to consume during this time. Not only will the increase in physical activity require more hydration due to water loss from perspiration (a little sweat is fine, but if the person is drenched in normal heat, then he or she should back off), but also because as the stored fat is burned and the muscles are exercised, all sorts of nasty things that were held inside them become free in the body.  If the hydration levels are low, those substances will be reabsorbed into the body, but with adequate water intake, the body will have a natural way to expel them.