Very few particles in the universe can be said to be essential to our lives. Water is an obvious candidate for that list, so is carbon because we are carbon-based life forms, and the third is oxygen. We all know oxygen. Frankly, we’d be dead if we didn’t.
Oxygen is the molecule we breathe in and out approximately 19,000 times a day without tiring ourselves out. Our respiratory system, like our cardiac system, is fine tuned by nature to ensure nearly constant supply of oxygen to our body throughout our lives. Its importance is evident from the many practical and hypothetical scenarios we can think of where a lack of oxygen for a long enough time is all that’s required to kill us. Think drowning in a deep-water body, strangulation victims, being in the vacuum of deep space without a protective space suit. It’s not hard to ascertain the need of oxygen for our survival. A quick look into the intricacy of this system allows better appreciation of the wonder that is breathing.
It all begins with the contraction of our diaphragm muscles, that decreases the air pressure inside our chest cavities below that of the atmospheric air, allowing the lungs to expand. The relatively higher air pressure outside the body the forces the air through our respiratory pathway comprising the nasopharynx, trachea, principle bronchi and then further divisions in these tubes down to the microscopic sacs called alveoli. Air flows down to the alveoli, each of which are roughly 80% surrounded by tiny blood vessels called capillaries. This is where gaseous exchange takes place. Oxygen from the air diffuses through the alveoli int the blood, while Carbon Dioxide diffuses out of the blood into the air in the alveoli.
Inspiration was the first half of the equation, the other half called expiration then takes over as the diaphragm muscle begins to relax. The relaxing diaphragm along with the innate elasticity of the lung tissue then works to return the lung to its previously deflated state. This attempt raises the pressure inside our chest cavities well above atmospheric air pressure and the same air that was first pushed in from the outside, is now pushed out from the inside. Air exits the same tubes it flowed in from, and the expiration phase is completed, ready for another round of inspiration and so on.
Regulation of breathing
Breathing as described above, is just one of the many systems in place that make sure our cells get the oxygen they need. Breathing itself is regulated at the molecular level by specialized cells in our body called Chemoreceptors, located at the bifurcation of the common carotid artery into the internal and external carotids in our neck. These cells sense the levels of oxygen and carbon dioxide in our blood and then send neural signals to our brainstem. These signals modulate the respiratory centers in our brainstem to alter our rate and pattern of breathing to adjust oxygen supply according to the demand in our bodies. You can easily understand this concept by picturing yourself running. Any state that increases the demand of oxygen in the body, such as running, happens through the chemoreceptor-brainstem system and as a result, you begin to breathe faster and deeper to increase the oxygen supply to meet this new demand. The opposite occurs when you sleep. Your body requires far less oxygen when you’re asleep and this is communicated to the chemoreceptor-brainstem system, and consequently, your breathing slows down.
WHY GO THROUGH ALL THE TROUBLE?
Reading all the above, it must have crossed your mind that there must be a good reason for this level of intricacy and efficiency of this system. Granted we are only able extract approx. 5% of the oxygen in the ambient air, as evident from pre-inspiration and post-expiration comparisons of oxygen percentage in the air, with pre-inspiration oxygen standing at 21% and post-expiration at 16%. But even then, the delivery system is very effective at tightly maintaining a very narrow range of oxygen concentration in our blood. So, why is this necessary? Why do we depend on it so much?
To understand that, we will side track a bit into chemical reactions territory to understand what exactly oxygen does. The reaction relevant to our physiology is oxygen’s ability to oxidize reactants into products, with the release of energy, called an Exothermic reaction. Exothermic reactions release energy from the conversion of reactants to products, and Endothermic reactions require energy to convert reactants into products. The most obvious exothermic reaction in our physiology is the conversion of Glucose, our primary nutrient, to Carbon Dioxide and Water. Many of you will be familiar with this conversion from your biology classes.
Oxygen plays a vital role in enabling this exothermic conversion which powers literally every single cell in the body. The energy released from this reaction is then trapped into our energy currency called Adenosine Triphosphate (ATP) and then thee ATP molecules are used to enable our hearts to beat and our lungs to breathe and our brains to think and you to read and comprehend this sentence. This reaction happens everywhere in our bodies and the carbon dioxide produced from it is the same carbon dioxide that diffuses out into the air through the alveoli. With roughly 37 trillion cells in our body constantly needing oxygen to power themselves and their processes, Oxygen earns its title as “essential”.
CAN WE DERIVE MORE BENEFITS FROM THIS OXYGEN?
From our discussion so far, we can see the important role oxygen plays for our lives. But is this all that oxygen can do for us? Or are there more benefits that can be extracted from the use of oxygen? Here is where we come back into biohacking territory as we explore the two ways we can take greater control over the benefits we can derive from the same oxygen we’ve been using ever since we took our first breath.
A constant supply of oxygen is what our biology has evolved over the millions of years we have spent time on this Earth. But one may begin to wonder what if we have less than the desired level of oxygen to consume, or what if we have more oxygen than our bodies require? Can there be any advantages to be had to the differing levels of oxygen in the atmosphere? Let’s look at how we can hack our own physiology and obtain greater gains by purposefully altering the oxygen supply our bodies can use.
On a biochemical scale, you and I live within a very very tightly regulated range. Just as our eyes are only able to capture the tiny sliver of electromagnetic spectrum that is visible light, our bodies too behave this way. All human life exists within the total range of just one pH. Oxygen and Carbon Dioxide also must be present in a very narrow range to be compatible with life. Concentrations of these gases in the blood are measured as "partial pressures" in arterial blood measured in millimetres of mercury (mmHg). The normal partial pressure of Oxygen in our blood is between 80 to 100 mmHg. Below 80 mmHg is what is called hypoxia (hypoxemia to be precise but for simplicity we will consider both to be the same), and above 100 mmHg is called Hyperoxia.
We will look at the potential advantages of both cases as well as the potential disadvantages and adverse effects to watch out for. Biohacking after all is supposed to give you more control over your own biology but not at the expense of your health.
Let us take a brief look into what scientific studies around the world have yielded as potential benefits of lower than normal oxygen pressures.
- Increased Red Blood Cell Thickness
Oxygen after diffusing into the blood from alveoli makes its first stay within our red blood cells, attached to a molecule called Haemoglobin. 98% of the oxygen that enters the blood from the lungs is bound to haemoglobin, with the remaining 2% freely dissolved in the plasma. The red cells then take this oxygenated haemoglobin around the body through our circulatory system to every tissue in the body and wherever the level of oxygen in the tissues is low, the higher pressure of oxygen in the blood causes it to dissociate from the haemoglobin and diffuse into the tissue for utilization.
Now all this works very well in the case of normal oxygen partial pressures. When oxygen is low in the blood, that's when the magic happens, albeit a little slower than we might like. See, when change is not too drastic, the human body is quite adaptable. With lower partial pressures of oxygen, the body has several ways to either increase the delivery of oxygen from the respiratory system or adjust its own cellular machinery to make the best possible use of the limited resource. One way it does that is by making the red cells thicker and able to pack in more haemoglobin than a normal cell would. This adaptation allows every red cell to absorb just a little bit more oxygen from the alveoli than it normally does, and the collective effect is a substantial increase in oxygen uptake. It cannot increase its haemoglobin indefinitely as it will eventually burst when its cell wall cannot take the pressure anymore. But this adaptation alone confers great advantage to the body when the oxygen pressures normalize. Now you have thicker red cells that allow your body to extract more oxygen than an otherwise normal person does.
- Increased Red Blood Cell Number
This is another adaptation that body goes through during long exposures to low oxygen pressure. And if you think about it, it makes perfect sense. Consider the body as a factory and every red blood cell as one worker. When the demand for performance is high, you can think of increasing the efficiency of each individual worker. That's what happens when the red cells thicken in volume. What else can be done? Increase your total workforce. Right?
The body goes through the same logic and has molecular countermeasures already set in place if there ever is a need for them. One compound that is produced in response to low oxygen levels is the Hypoxia Inducible Factor 1 (HIF-1). This factor is coded on DNA and its gene is expressed whenever there is a long enough exposure to low oxygen. HIF-1 after formation travels to the kidneys where it stimulates the increased production of another important compound called Erythropoietin.
Erythropoietin is a peptide hormone that then travels to our bone marrows and essentially turns them up a notch. The bone marrow then starts producing more red blood cells from progenitor stem cells and our factory now has a bigger workforce to carry even more oxygen to the tissues. This condition is called Polycythaemia.
Polycythaemia in response to hypoxia is a well documented phenomenon and is routinely applied by athletes to boost their respiratory capacity. Polycythaemia also confers stamina and endurance boosts not when we're under hypoxia but when we eventually return to normal oxygen levels. Now you not only have a greater number of red cells but they all are packed to the max with haemoglobin to further enhance our oxygen delivery mechanism.
While all this sound very lucrative, it does come with its own catch. This adaptation takes time. Athletes usually must spend several months under low oxygen environments to be able to stimulate these adaptive changes.
METHODS TO INDUCE HYPOXIA
So far, we know what advantages we can gain from hypoxia induced adaptations in the body. Now let's look at how to safely generate the hypoxia that will stimulate our adaptation process.
- High Altitude Training
By far the simplest and most obvious method of boosting your red cell capabilities is by spending time in a high-altitude environment where the oxygen levels are lower than they are at sea level. You will see many athletes and military personnel adopt this approach with training camps and military bases being located amongst the mountains. The drop-in oxygen levels are not too drastic to irreversibly damage our body but is still enough to make normal activities you do at sea level feel exhausting up there.
We advise taking it slow up there as you cannot will your body to adapt faster than it feasibly can. Start the same as you would at sea level if you never exercised before. Daily brisk walks are an excellent way to start. Experts recommend a minimum of 15 minutes of brisk walking daily for at least 5 days a week as not only beneficial for the respiratory adjustment but also for overall cardiovascular health. Once this level of exercise becomes non-tiring, you can move up to more strenuous activities. Remember, it takes time.
- Hypoxia Chambers and Altitude Tents
Hypoxia chambers are devices of varying sizes that simulate high altitude conditions by artificially lowering the oxygen levels in the ambient air, while Altitude Tents are often paired with hypoxia chambers to provide low oxygen levels even while resting. Athletes and especially fighter jet pilots train in such conditions when training in actual high altitudes is not feasible. The effect is like high altitude training with increase in the efficiency of oxygen delivery at the red blood cell level.
Additionally, hypoxia chamber also uses a tight-fitting hypoxia mask to deliver the modified air through. Elevation masks are a popular method to produce hypoxic conditions without the use of a hypoxic chamber by making it harder to breathe physically. However, when compared with hypoxia chambers and high-altitude training sessions, studies have shown that elevation masks do not produce the same adaptations that the abovementioned methods do, despite elevation masks making the physical act of breathing difficult. Hypoxia chambers and tents are becoming increasingly affordable and if you do not wish to spend time in higher altitudes then these might be a good fit for you.
Hyperoxia or Hyperoxemia is the condition where the partial pressure of oxygen within the blood is above 100 mmHg. As we've seen in the previous section, the ends of the normal ranges of oxygen have the potential to lend us some unique advantages if used right and safely. Just as hypoxia can have its perks, so can hyperoxia, as we will discuss in this section.
Hyperoxia is a well documented condition and modern medicine makes use of it as well. In many studies the use of hyperoxia instruments before giving general anaesthesia to patients about to undergo surgical procedures, the oxygen levels that normally would drop once the patient goes under, remained surprisingly well for up to 5 minutes even without the patient needing to put on a mechanical ventilator before the first incision is made.
Deep sea divers and professionals who attempt at breaking the world record for holding their breath (currently standing at a whopping 24 minutes and 37 seconds set by Budimir Sobat of Croatia on 27th March 2021) also make use of this concept by hyperventilating before beginning their attempt. Hyperventilation or rapid deep breathing quickly adds a lot of oxygen into our systems while washing out a lot of carbon dioxide (high carbon dioxide levels in the blood being important molecular triggers for breathing at the chemoreceptor level). This allows their bodies to go on for longer times without needing to breathe.
Besides the ability to hold your breath for longer than usual, what other benefits can be derived by using higher than normal oxygen levels? Many of the following benefits revolve around one common theme: Oxygen powers almost all processes of the body. Let's see exactly how.
- Quicker Resolution of Inflammation
Inflammation is the body's response to pathogenic organisms and foreign bodies. The immune system recognizes that the entities are alien to this body and so mount their immune response. Inflammation is one of those responses with the immune system sealing off the area the way the police do in a hostage situation. Inflammatory cytokines are activated, and white blood cells then storm the scene to destroy the invaders. In the short term this response is incredibly beneficial as a line of defence against disease. However, the longer it goes the greater the toll it takes on the body.
This is where hyperoxia comes into play. Increased levels of oxygen not only power the initial inflammation but also prevent it from becoming chronic by powering the clean-up crew. If normal inflammation is the police, then you can think of hyperoxia's effect as being the Seal Team 6 that gets the same job done faster and more efficiently.
- Quicker Recovery and Healing
Studies in which participants had long term diabetes and chronic non-healing diabetic ulcers, when routinely exposed to hyperoxic environments showed a faster rate of healing as compared to normal rates. This brings us back to the main concept of Oxygen powering almost all processes of the body. In this example it is the repair process that is dialled up a notch thanks to higher oxygen levels. More oxygen means more energy and more energy means faster healing. While it may not grant you Deadpool or Wolverine levels of healing factor, it's still better than normal rates don't you think?
Studies involving patients with radiation induced wounds and hypoxia inducing varieties of certain tumours also fared better in hyperoxic environments as compared to normal.
By far the most common benefit derived from hyperoxia is that of quick recovery from fatigue. You may have seen NFL players breathing through special apparatus during match breaks and professional cyclists, runners and even soccer players training with what looks like a hypoxic chamber. Oxygen is required to return fatigued muscles back to their active ready-for-another-match state and logically, hyperoxia should do that faster right?
Studies in sports medicine have shown that hyperoxic delivery hastens the recovery process for fatigued muscles by a different process than hypoxia. We saw that hypoxia stimulated the adaptation of red blood cells. Hyperoxia however does not increase red cell efficiencies but increases the efficiency of the 2% of oxygen dissolved in the plasma. Plasma oxygen delivery, once enhanced by hyperbaric oxygen delivery, allows the muscles to make use of both red cells and plasma to replenish its energy stores.
METHODS OF UTILIZING HYPEROXIA
Like hypoxia, there are a few ways to generate hyperoxic environments to aid the body in faster recovery. Unlike hypoxia however, all the following methods are artificial attempts as there is no natural way to produce intermediate to long term hyperoxia.
- Hyperbaric Oxygen Therapy (HBOT)
Hyperbaric chambers, like hypoxic chambers, artificially create higher than normal oxygen levels in the air within them that is delivered via a tight-fitting mask. This method is becoming increasingly popular among the masses because of its routine use in sports. Hyperbaric oxygen delivers all the above-mentioned benefits of hyperoxia and more as studies keep unravelling newer benefits of HBOT from therapeutic uses in Asthma and COPD as well as in Carbon Monoxide (CO) poisoning where CO binds to haemoglobin with a far stronger bond that Oxygen has, forming Carbaminohemoglobin and therefore HBOT is required to replace the 200 times more strongly bound CO with normal Oxygen bound Haemoglobin (Oxyhemoglobin)
HBOT has shown tremendous value in treating people with decompression sickness (Caisson Disease or "The Bends") such as deep-sea divers. Decompression sickness occurs when the divers ascend to the surface and the dissolved gases in their blood form bubbles that wreak havoc on their bodies producing intense pain. Hyperbaric chambers are used to simulate the deep-sea environment and then the gas levels are carefully brought back to normal, allowing the diver's body to adjust accordingly instead of getting the bends from sudden pressure changes.
Similarly, premature infants that have underdeveloped lungs or those who suffer from birth asphyxia due to prolonged labour also benefit from HBOT in specially designed paediatric incubators where their blood oxygen levels are measured and protected from hypoxic brain damage by giving them hyperbaric oxygen to utilize until their own respiratory systems mature.
HBOT has a host of different benefits and as they are becoming more affordable with time and better technology, hyperbaric oxygen therapy (HBOT) is showing promise in the fields of medicine, sports physiology and natural human enhancement. Among the biohackers community, HBOT is quickly gaining fame as the next big thing because of the potential of faster, more efficient repair. Extrapolation of this one prospect may even allow HBOT to significantly enhance quality of life and maybe even prolong life by decreasing mortality due to natural causes. More studies are being done on this subject, but we are hopeful to use it to live longer and healthier.
- Oxygen Concentrators
Oxygen concentrators are devices that take in their surrounding air and by expelling the other natural gases like nitrogen and carbon dioxide, deliver a concentrated mixture of the ambient air. Their efficacy in terms of generating the hyperoxia response from the body is comparatively lesser than that of proper HBOT however they can also be used for short term benefits especially in medical conditions that require supplemental oxygen such as different Pneumonias, Heart Failure and Pulmonary Oedema, Chronic Obstructive Pulmonary Disease from years of exposure to tobacco smoke, and more commonly now, in COVID-19.
Oxygen is a vital resource required by our body to turn our fuel, Glucose, to energy and then that energy drives nearly every biological process within our bodies. Normal oxygen pressures have proven themselves to be essential to our survival, but due to the body’s range of adaptability, there is a certain degree of benefits to be gained from lower and higher than normal oxygen pressures.
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