Hematocrit drives Blood Viscosity- Does that Matter in Men on TRT? Effect of Altitude?

[FunkOdyssey]

Sounds good on paper. Unfortunately that craze fell out of favor pretty quick. I remember back on dr crislers forum how pregnenolone was going to be the savior for all. Turns out very few actually felt better on it. (Not saying it isn’t great for some)

Backfilling the upstream hormones with pregnenolone makes so much intuitive sense as a theory that you just know it is doomed in real life. Maybe if you want to pulse GnRH five times a day like Cataceous, that probably works. I'm sure he wouldn't bother with all that if a simple pregnenolone capsule had the same effects.

 

[Charliebizz]

Backfilling the upstream hormones with pregnenolone makes so much intuitive sense as a theory that you just know it is doomed in real life. Maybe if you want to pulse GnRH five times a day like Cataceous, that probably works. I'm sure he wouldn't bother with all that if a simple pregnenolone capsule had the same effects.

Exactly. for Some people they feel better on preg. but By what mechanism who knows. If back filling worked the way it would Naturally then us secondary guys wouldn’t even need trt in the first place in most cases.

 

[Gman86]

Do you believe erythrocytosis is harmless? Is that a good way to phrase that question? Curious your thoughts with the information available on this site.

Definitely don’t think it’s harmless. Don’t think anyone can say that it’s harmless. Everything in the body works on a balance system. Anytime the body has too little or too much of something, or too low or too high of something, it’s going to cause issues. So erythrocytosis is obv no different

The answer to ur question is complicated tho. So many factors have to be considered. Do I personally worry about a HCT level of 55 or lower in myself, no. Because I know all my other risk factors for having any issues cardiovascularly are very low. Would I be super concerned if my HCT went up to 56 or 57? Not really. But I would personally donate blood and get it down a bit just as a precautionary measure. Luckily HCT is not something I have to worry about tho. Mine has run between 49-51 for a while now, despite my dosages being the highest they’ve ever been, and using compounds like nandrolone and primobolan.

As far as giving my opinion on having an increased level of RBC’s with others, I’d have to take it on a case by case basis. I’d have to know where their HCT level sat, how hydrated they were at the time of their labs, what their platelet level was, whether they had insulin resistance going on, and to what degree if they did. So I would want to know what their triglyceride level was, what their fasted insulin level was, and preferably what their A1C level and fasting glucose was. The fasting glucose level being the least important out of all those markers. But still somewhat helpful if I could see what it was. That’s probably all I would need to make a decent assessment of whether I thought their HCT level was something to be concerned with or not. Obv the more info the better tho. So it would help a bit more to know what their vitals consistently were, as well as their past medical history, what meds they’re on, and what their diet and lifestyle looked like, so I could assess how much inflammation they most likely have going on. And obv height, weight and age would be helpful

 

[tareload]

Don’t think anyone can say that it’s harmless.

Thank you for your fair and detailed response. I agree with your points.

Do you think this video and message is medically reckless (as well as getting a bunch of technical points wrong)?

Still no word from @RobRoy on this....

Post in thread 'What is TRT and What is NOT TRT' What is TRT and What is NOT TRT

 

[Gman86]

Thank you for your fair and detailed response. I agree with your points.

Do you think this video and message is medically reckless (as well as getting a bunch of technical points wrong)?

Still no word from @RobRoy on this....

Post in thread 'What is TRT and What is NOT TRT' What is TRT and What is NOT TRT

Ya I definitely don’t agree with what he’s saying. He’s looking at it in too much of a black and white way. The body is way too complicated, and so many systems are working together at all times, to look at anything in the body in such a black and white/ simplistic way. His comment at the end simply isn’t true. He says that erythrocytosis is harmless, and nobody on HRT should ever consider doing a phlebotomy. I definitely can’t get behind those views. However, do I think that a lot of people on HRT unnecessarily worry too much about their HCT levels being too high, yes I do.

 

[tareload]

Ya I definitely don’t agree with what he’s saying. He’s looking at it in too much of a black and white way. The body is way too complicated, and so many systems are working together at all times, to look at anything in the body in such a black and white/ simplistic way. His comment at the end simply isn’t true. He says that erythrocytosis is harmless, and nobody on HRT should ever consider doing a phlebotomy. I definitely can’t get behind those views. However, do I think that a lot of people on HRT unnecessarily worry too much about their HCT levels being too high, yes I do.

Thank you @Gman86. I appreciate your time to share your thoughts on this. Your comments have been what I have been trying to get TOT Land to recognize for many years. I will concede your last sentence as well. The individual must be careful with their individual case.

 

[FunkOdyssey]

View attachment 34949

Sorry to be the bearer of bad news, but I heard Bill is no longer with us. It seems he died recently of a heart attack. Bill's TOT practitioner blamed the COVID vaccine but I think it may have had something to do with his 50 ng/dl free testosterone and 57% hematocrit combined with metabolic syndrome and obesity.

 

[tareload]

Sorry to be the bearer of bad news, but I heard Bill is no longer with us. It seems he died recently of a heart attack. Bill's TOT practitioner blamed the COVID vaccine but I think it may have had something to do with his 50 ng/dl free testosterone and 57% hematocrit combined with metabolic syndrome and obesity.

Sorry to read that. Damn.

Glad that Jay is still rocking hard. Ignorance is bliss I hear. That dude is a stud.

 

[Phil Goodman]

Do you believe erythrocytosis is harmless? Is that a good way to phrase that question? Curious your thoughts with the information available on this site.

I think it depends on the cause. Having a disorder that results in erythrocytosis is different than someone living at higher altitudes. Also, exercising can increase hematocrit. Does that mean that is a negative aspect of exercise, is it good because your body adjusts, or is it neither good nor bad? Same with TRT…if it slightly raises it as an adjustment that your body makes is it automatically bad? I wouldn’t think so if your overall health is good otherwise. Sure it could be bad for some people, but saying slightly elevated hematocrit is automatically worse than having it in range is a blanket statement that disregards lots of other factors.

 

[Nelson Vergel]

Hematocrit (HCT) is a measure of the proportion of blood volume that is occupied by red blood cells. It is often used as an indicator of the oxygen-carrying capacity of the blood. Increases in HCT can be caused by a variety of factors. In your question, you mention two specific scenarios: living at high altitude and undergoing testosterone replacement therapy.

High Altitude: When someone lives at high altitude, the air is thinner and contains less oxygen. In response to this low-oxygen environment, the body increases the production of erythropoietin, a hormone that stimulates the production of more red blood cells. This increase in red blood cells elevates the hematocrit level. The main purpose is to carry more oxygen to the body's tissues to compensate for the lower oxygen levels in the air. This is a natural physiological response to the environmental condition.

Testosterone Replacement Therapy: Testosterone is known to stimulate erythropoiesis (the production of red blood cells). When someone is on testosterone replacement therapy, the increased levels of testosterone can lead to a higher production of red blood cells, thereby increasing the HCT level. This is a side effect of the hormone therapy and is not related to the body's need for oxygen.

In both scenarios, the increased hematocrit can thicken the blood, which potentially increases the risk for clotting and cardiovascular events. However, people who live at high altitudes over long periods typically have adaptations that help protect them from these risks. These adaptations may not occur in people with high HCT due to testosterone therapy.

The key difference between these two situations is the reason behind the increased HCT. At high altitudes, the body is trying to compensate for less available oxygen, while in testosterone therapy, it is a side effect of the treatment. Moreover, the potential risks associated with high HCT might be different based on the individual's overall health status, the presence of other risk factors, and the duration of high HCT.

There's not a clear consensus in the scientific community on whether living at high altitudes provides a protective effect against cardiovascular diseases. Some studies suggest potential benefits, while others don't.

Certain research indicates that people living at higher altitudes may have lower rates of mortality from ischemic heart disease, although the reasons for this aren't entirely clear. Proposed mechanisms include lower levels of oxygen at high altitudes leading to the development of more blood vessels, a higher metabolic rate, which could help with weight maintenance, and adaptations in the body that improve oxygen and carbon dioxide transport.

However, living at high altitudes can also come with some potential downsides. For example, chronic exposure to lower levels of oxygen (hypoxia) can lead to an increase in red blood cell production and blood viscosity, which could potentially increase the risk of certain cardiovascular events like thrombosis. Altitude has also been shown to potentially exacerbate certain conditions, like pulmonary hypertension.

It's also important to note that other factors often vary with altitude, such as lifestyle, diet, physical activity levels, and access to healthcare. These can all significantly impact rates of cardiovascular disease and should be considered when evaluating the relationship between altitude and heart health.

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Normal Hematological Values for Healthy Persons Living at 4000 Meters in Bolivia​

Defining the range of normal hematocrit and hemoglobin levels in residents of high altitude is required to diagnose chronic mountain sickness (CMS) and other conditions defined, in part, by hematocrit or hemoglobin values. We studied 1,934 healthy, young (aged 15 to 29 yr) male and female residents of Potosí, Bolivia (4000 m), to determine the average and normal range of hemoglobin and hematocrit values, defining normal as within 2 standard deviations of the mean or encompassing 95% of the observed variation. Male hematocrit averaged 52.7% and hemoglobin averaged 17.3 m/dL whole blood.

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ALTITUDE ADAPTATION THROUGH HEMATOCRIT CHANGES



The PDF file discusses altitude adaptation through hematocrit changes, with a focus on high altitude adaptation. The article determines the stages of high altitude adaptation, with three stages including acute, subacute, and chronic. Changes in hematocrit are studied in one high altitude resident traveling between La Paz and Copenhagen and in two low-landers traveling from La Paz to Copenhagen. Adaptation time is altitude and time dependent and can be calculated through a simplified equation.

How do changes in hematocrit occur when traveling between high altitudes and sea level?


Going from sea level to high altitude requires about 40 days to achieve a complete adaptation. Conversely, going back down to sea level requires about 20 days for the adaptation to occur. A 50% of the adaptation is reached when the hematocrit is at 43%, which is achieved at around 1 week. On the contrary, upon descent, there is a relative increase in plasma volume and subsequent dilution of the blood, known as hemo-dilution.

High altitude adaptation refers to the physiological changes that occur in response to the decrease in oxygen availability at high altitudes. Three stages characterize high altitude adaptation:
1) Acute, the first 72 hours, where acute mountain sickness can occur.
2) Subacute, from 72 hours until the slope of the hematocrit increase with time is zero, where subacute high altitude heart disease can occur.
3) Chronic, where the hematocrit level is constant, and the healthy high altitude residents achieve their optimal hematocrit.
High altitude adaptation is altitude and time-dependent, and the optimal hematocrit level is achieved after about 40 days of exposure to high altitude.


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The mean hematocrit was significantly higher at high altitude (47.5% versus 41.3%; p < 0.0005) as were the mean serum cholesterol (190 mg/dL versus 177 mg/dL; p < 0.002) and the low-density lipoproteimhigh-density lipoprotein ratio (2.80 versus 2.27; p < 0.05). Whereas a significant, positive relationship existed between hematocrit and cholesterol at low altitude (2.15 mg/dL per %; p < 0.002), no such relationship was found at high altitude. Hematocrit and serum cholesterol were elevated for family practice patients living at high altitudes. Differences exist between altitudes in the relationship between hematocrit and cholesterol. Acclimatization to high altitude and its resultant erythropoiesis may increase serum cholesterol levels. Consequently, relocation to a high altitude may increase the risk of arteriosclerotic cardiovascular disease.

Elevation of serum cholesterol at high altitude and its relationship to hematocrit

The positive relationship between hematocrit and serum cholesterol may be due to dilution. Accordingly, high hematocrits would yield reduced serum poo…

www.sciencedirect.com

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Effects of Living at Higher Altitudes on Mortality: A Narrative Review

Beside genetic and life-style characteristics environmental factors may profoundly influence mortality and life expectancy. The high altitude climate comprises a set of conditions bearing the potential of modifying morbidity and mortality of approximately ...

www.ncbi.nlm.nih.gov

Beside genetic and life-style characteristics environmental factors may profoundly influence mortality and life expectancy. The high altitude climate comprises a set of conditions bearing the potential of modifying morbidity and mortality of approximately 400 million people who are permanently residing at elevations above 1500 meters. However, epidemiological data on the effects of high altitude living on mortality from major diseases are inconsistent probably due to differences in ethnicity, behavioral factors and the complex interactions with environmental conditions. The available data indicate that residency at higher altitudes are associated with lower mortality from cardiovascular diseases, stroke and certain types of cancer. In contrast mortality from COPD and probably also from lower respiratory tract infections is rather elevated. It may be argued that moderate altitudes are more protective than high or even very high altitudes. Whereas living at higher elevations may frequently protect from development of diseases, it could adversely affect mortality when diseases progress. Corroborating and expanding these findings would be helpful for optimization of medical care and disease management in the aging residents of higher altitudes.

 

[aloetard]

Does a high hematocrit change your blood's clotting profile? High altitude vs TRT.

Does having a high hematocrit mean your blood is more likely to clot? This study looks at a city where people with the highest hematocrit in the world live and work.

www.excelmale.com

Shear stress as a function of whole blood viscosity in blood vessels. Cross reference.

I'll leave it to Robroy to provide the particular solution for shear stress at the vessel wall. Help us out Sir. Seriously though, take a look below. Would love to find common ground with you Dr N. I did extend the olive branch over a TNation one time. Life is short.

 

[Charliebizz]

Does a high hematocrit change your blood's clotting profile? High altitude vs TRT.

Does having a high hematocrit mean your blood is more likely to clot? This study looks at a city where people with the highest hematocrit in the world live and work.

www.excelmale.com

Shear stress as a function of whole blood viscosity in blood vessels. Cross reference.

I'll leave it to Robroy to provide the particular solution for shear stress at the vessel wall. Help us out Sir.

Welcome back brother lol

 

[Seagal]

Does a high hematocrit change your blood's clotting profile? High altitude vs TRT.

Does having a high hematocrit mean your blood is more likely to clot? This study looks at a city where people with the highest hematocrit in the world live and work.

www.excelmale.com

Shear stress as a function of whole blood viscosity in blood vessels. Cross reference.

I'll leave it to Robroy to provide the particular solution for shear stress at the vessel wall. Help us out Sir.

I cannot find the statement of shear stress at the vessel wall. The video you referred me to explained that there is a layer of plasma at the vessel wall and that viscosity actually decreases below 2mm diameter with still having this plasma layer.

 

[aloetard]

I cannot find the statement of shear stress at the vessel wall. The video you referred me to explained that there is a layer of plasma at the vessel wall and that viscosity actually decreases below 2mm diameter with still having this plasma layer.

The theoretical derivation for arterioles was in the second link I provided (see the link under Competing effects. If you don't want to read the paper ...

The Effect of Small Changes in Hematocrit on Nitric Oxide Transport in Arterioles

We report the development of a mathematical model that quantifies the effects of small changes in systemic hematocrit (Hct) on the transport of nitric oxide (NO) in the microcirculation. The model consists of coupled transport equations for NO and oxygen ...

www.ncbi.nlm.nih.gov

Even in arterioles there would be very linear relationship with Hct and shear stress at wall.

Another link to full paper:

The Effect of Small Changes in Hematocrit on Nitric Oxide Transport in Arterioles

We report the development of a mathematical model that quantifies the effects of small changes in systemic hematocrit (Hct) on the transport of nitric oxide (NO) in the microcirculation. The model consists of coupled transport equations for NO and oxygen ...

www.ncbi.nlm.nih.gov

 

[aloetard]

Enjoy.

https://journals.physiology.org/doi/full/10.1152/japplphysiol.91013.2008

Effects of hematocrit levels on flow structures and stress levels in the healthy and diseased carotid arteries

Flow structures and wall shear stress (WSS) distribution in human arteries depend strongly on blood rheology. Blood viscosity undergoes significant alterations

pubs.aip.org

Specifically, we consider high (65%) and low (25%) Hct levels in addition to a normal Hct level. Our results reveal that both high and low Hct levels have adverse effects on the hemodynamic features inside a healthy carotid artery model. The low Hct level displays a much more widespread low time-averaged WSS (TAWSS) area, while the high Hct shows an increased oscillatory shear index (OSI) zone at the carotid sinus wall. In stenotic arteries, low Hct enhances the spread of the low TAWSS zone in the post-stenotic carotid sinus, whereas high Hct increases the risk of plaque rupture. The high Hct level also increases the spread of high OSI zone at the inner wall of internal carotid artery for the moderately stenosed artery.

You can spend a great deal of time looking into details of the interplay of Hct, vessel compliance, plasma viscosity, geometry, NO production, amount of vasodilation and their effects on wall shear stress (WSS). Make sure your whole blood viscosity (WBV) is where you want it depending on whether you want physical performance or longevity. The scientific literature is pretty clear there is a tradeoff based on what we know about human physiology.

 

[Seagal]

Enjoy.

https://journals.physiology.org/doi/full/10.1152/japplphysiol.91013.2008

Effects of hematocrit levels on flow structures and stress levels in the healthy and diseased carotid arteries

Flow structures and wall shear stress (WSS) distribution in human arteries depend strongly on blood rheology. Blood viscosity undergoes significant alterations

pubs.aip.org

You can spend a great deal of time looking into details of the interplay of Hct, vessel compliance, plasma viscosity, geometry, NO production, amount of vasodilation and their effects on wall shear stress (WSS). Make sure your whole blood viscosity (WBV) is where you want it depending on whether you want performance or longevity. The scientific literature is pretty clear there is a tradeoff based on what we know about human physiology.

Thanks a lot, aloetard. That's real research, love it!
Hey, I'm not a proponent of high hct. Previous generalized warnings and discussions just didn't make much sense to me. I prefer mental performance and longevity.

 

[aloetard]

Thanks a lot, aloetard. That's real research, love it!
Hey, I'm not a proponent of high hct. Previous generalized warnings and discussions just didn't make much sense to me. I prefer mental performance and longevity.

Thanks for discussing all this. Nice chatting with you.

Here's another discussion of various theories of how the body sets Hematocrit (in the absence of exogenous T use). I am still concerned with interplay between Hct and plasma viscosity with T use. I can see where using T may increase Hct and decrease plasma viscosity in the obese as they lose weight and achieve better fitness. Where whole blood viscosity ends up is the question? Also consider increased cardiac workload with exogenous T use. Why?

My primary concern is the argument that any and all elevations in Hct are harmless and the body will always adapt.

More. Think about this...

Letter to editor:

https://journals.physiology.org/doi/full/10.1152/japplphysiol.00957.2012

In response to:

https://journals.physiology.org/doi/full/10.1152/japplphysiol.00369.2012

 

[Seagal]

Thanks for discussing all this. Nice chatting with you.

Here's another discussion of various theories of how the body sets Hematocrit (in the absence of exogenous T use). I am still concerned with interplay between Hct and plasma viscosity with T use. I can see where using T may increase Hct and decrease plasma viscosity in the obese as they lose weight and achieve better fitness. Where whole blood viscosity ends up is the question? Also consider increased cardiac workload with exogenous T use. Why?

My primary concern is the argument that any and all elevations in Hct are harmless and the body will always adapt.

More. Think about this...

Letter to editor:

https://journals.physiology.org/doi/full/10.1152/japplphysiol.00957.2012

In response to:

https://journals.physiology.org/doi/full/10.1152/japplphysiol.00369.2012

You have ruined my day. Sometimes ignorance is a bliss
I will try to find out what my hct was in past.

 

[aloetard]

Welcome back brother lol

Thank you Sir. Good to hear from you.

 

[Seagal]

Any scuba diver on board?
I have always had relatively low air consumption. Dive instructors judge this as high level of experience. However, I'm a once per year recreational suba diver.
Now I thought that I might have had higher than average hematocrit before TRT and this might be a contributing factor. Anyway, couldn't find any scuba science about it.
Aloetard sparked my interest in that topic.

The following article is probably not up to date but more holistic and much less detailed than previously posted articles.

Red blood cells in sports: effects of exercise and training on oxygen supply by red blood cells

During exercise the cardiovascular system has to warrant substrate supply to working muscle. The main function of red blood cells in exercise is the transport of O[2] from the lungs to the tissues and the delivery of metabolically produced CO[2] to ...

www.ncbi.nlm.nih.gov