Body Sensors -- What Your Body Tells You

     Our bodies have the capacity to tell us a lot about our health and what we need to do to feel our best. Alas, we also have the ability to ignore these signs and an aspect of our modern society is to encourage us to do so.
     When people think about "sensors" they usually think about electronic automation. There is a sensor to tell your thermostat whether to turn on the heater or air conditioner. There are sensors in ovens and toasters to indicate when proper temperature at appropriate times has been applied. There are sensors in our cars to indicate proper fuel intake and when to shift gears and even to apply brakes or throttle. We have similar things within our bodies. Much of robotics is concerned with getting machines to be able to do the same things we do every day.
     The first sensors that come to mind for people is our " five senses". These are usually listed as sight, hearing, touch, taste, and smell. Some people add a "sixth sense" to indicate information we take in that are not easily linked to the five physical senses.
     However, we also have a lot of internal sensors -- primarily associated with the way that our brains are able to interpret specific signals. We can tell, via pressure at specific points, whether we need to urinate or defecate. We can tell if our stomachs are adequately full. The sense of cold and heat can easily be fooled because it is associated with the way specific nerves under our skin react to temperature differences. Sometimes these interact with certain organs -- such as our inner ear -- to tell us whether we are level or spinning and help with the ability to move smoothly.
     The third category of sensors is difficult to understand fully. Our brains have access to much information that requires a host of tests to determine externally. They have access to insulin levels, to endocrine levels, to the amount of oxygen being carried by our blood, and to the levels of neurotransmitters and other chemicals in our brains and bodies. Much of the time, our bodies work with this data automatically by use of the "brain stem". However, it is possible for people to access this information consciously and actively apply responses.
     So, what does all of this information tell us? It tells us when we are hungry or full, whether we are hot or cold, and whether the food, drink, or other substance we might bring into our bodies is good for us or not. It tells us whether we need to use the restroom. It also tells us whether we are tired, sad, happy, stressed, excited, and just (all in all) how we feel.
     Consider now the various items that often exist in our homes, or in the supermarket/pharmacy, or being advertised as services for us. Many of these exist because we do not pay attention to the information our bodies tell us. Why not? The pressures of a time-obsessed society cause us to eat quickly (not giving time for us to listen to body signals), and schedules tell us when we can eat/drink and do other bodily functions. The allure of a "quick fix" stops us from adopting a lifestyle where we get the proper exercise and sleep. Calorie-dense food is easily available and our bodies did not develop to allow for such. Plus, we often feel that it is a "reward" to do things that our bodies do not want or need -- that extra large dessert or an "extra large drink".
     It isn't easy to change and our economic society does not encourage us to change. However, if we allow ourselves to listen to what our bodies tell us then we can be healthier and happier.

Smoke Gets in Your Lungs

In the present day, there's a lot of controversy about smoking. Old substances (tobacco) are in decline and are often under public disdain. "New" ones (marijuana) are in ascendance and are becoming more acceptable and may even cross the line back into legality (it's not really new and has a long history of various stages of legality -- see the Wikipedia entry Legal History of Cannabis).

However, because of its controversial legality and use, the health aspects of marijuana smoking have not been pursued as it has been for tobacco. There are also other substances that are sometimes smoked -- heated and inhaled or brought into the mouth. So, let's take a step back and just look into the smoke.

Smoke occurs when substances are burned. Many firefighter (and people trapped in fire areas)  injuries are associated with smoke inhalation. There are good (but highly technical) sources such as Wikipedia for articles on the various possibilities depending on factors such as heat, presence of other substances, humidity, and so forth. In this blog, we will concentrate on the tobacco and marijuana smoke voluntarily inhaled in relatively limited amounts by "smokers" and "tokers".

Smoke has four major aspects: carbon monoxide, tars and particulates, active ingredients, and additives.

1. Carbon Monoxide. This gas is created by incomplete burning of the material. It is primarily a danger to those "inhaling" as it is more lung-related. It is present in all smoke in varying degrees and is considered to be a poison as the body will absorb it and it decreases general function and may cause death. It is absorbed into the blood cells and decreases the ability to absorb oxygen and, thus, reduces stamina and general ability to perform at optimum levels. There is little difference in the effects between tobacco and marijuana smoke.
   
   
2. Tars and Particulates. These are the visible parts of smoke -- if you can see it, they are present. They are what cause the darkened areas of X-rays of lungs. "Tars" are resinous substances -- usually quite sticky and they cause the staining of teeth (and lungs) and can act as a kind of glue in the lungs, reducing the ability of the lungs to absorb oxygen. The particulates can vary in size depending on the temperature of the burning material and the size of the parts being burned and can act as an irritant causing more mucous production which is a major cause of "smoker's cough". It takes about five years for the lungs to fully repair from the damage caused by these substances and is considered to be a major trigger of lung cancer. This area could use more study but it is likely that there is little difference between tobacco and marijuana smoke.
   
   
3. Active Ingredients. These are the substances that interact with other parts of the body to cause the effects anticipated by smokers and tokers. In tobacco, this substance is nicotine which has many effects but primarily acts as a stimulant. It also has a mile diuretic (body water removing) effect which may cause weight loss for beginning smokers (and cause some temporary weight gain after quitting). It is water-soluble and, thus, is ideally administered via smoking. Anecdotally, nicotine is considered to help general focus and mental activity but there are no controlled studies verifying this. Nicotine also tends to paralyze the cilia in the trachea (windpipe) and, thus, may increase mucous retention and coughing. There are a few minor medical purposes for nicotine but it is highly physically addictive
   
   The primary active ingredient in marijuana is tetrahydrocannabinol (usually referred to, for obvious reasons, as THC). Its effects vary from individual to individual and is considered primarily a "psychoactive" (acting primarily on the central nervous system) drug. Common effects include increased appetite, decreased nausea and pain, and a reduced sperm production in men. It is not considered to be highly physically addictive although a varying amount of emotional or psychological addiction is possible for both marijuana and tobacco.
   
   
4. Additives. Since tobacco has been legal for many years and is a highly competitive industry, each company does what it can to both distinguish and "enhance" its brand of tobacco. Glycerin is normally added to increase shelf life and prevent the tobacco from drying out. Formaldehyde (think of frogs in jars in biology class) is added to make absorption and crossover to the brain more rapid. This increases the risk of physical addiction. Many other additives are also present -- from spices such as cinnamon and cloves to liquids such as menthol and other oils. Formaldehyde is known as a carcinogen and the burning by-products of the other additives have not been extensively tested. However, this is an area that is highly likely to contribute to act as cancerous triggers (especially for non-lung-related cancers). Tobacco is much worse in this area than marijuana.

Inhaling or not inhaling? As a water-soluble drug, the effects of nicotine are dependent upon the surface area times the duration of exposure. This is also true for other additive burn by-products. Thus, inhaling would be worse if holding it in the mouth was done for the same amount of time. However, this is not actually the case as cigar and pipe smokers tend to allow the smoke to remain in their mouths longer. Thus, there may be close to the same exposure for nicotine and additives. However, there would still be greatly reduced effects from the carbon monoxide and particulates. With THC, it varies upon the general environment. It is not considered to be water-soluble but it IS lipid (fats) and alcohol-soluble so, if taken with food or drink, it is probably absorbed as readily (or more readily) than bringing into the lungs.