Vitamin A Toxic?

[burtlancast]

Also Rami Nagel who wrote "cure tooth decay" died of cancer too.

He died of a rare form of brain cancer, brain stem glioma.

 

[Tarmander]

- Kim Schuette, a WAPF board member and nutritionist associated with promotion of FCLO, died earlier this week, Christmas day, at age 59. She is one of three WAPF-associated individuals who have died of glioblastoma brain cancer.

—Cherie Calvert, who was a founding member of the WAPF board, died in late November of breast cancer; she was 63. Calvert wasn’t known to have recommended or taken the FCLO, but had remained with the board as it fought off demands that it step back from its enthusiastic endorsement of the Green Pasture product.

—Jessica Earle was a long-time WAPF enthusiast and mother, who died last month at age 44, also of glioblastoma stage IV. She was unusual in that she lived for six years with the brain cancer, apparently benefiting from treatment by a prominent alternative practitioner. She had a blog chronicling her illness and sought funds to help defray costs of her treatment.

—Eoin Miller, a WAPF chapter leader in Ireland, died in late 2017 from liver cancer. He was a GAPS practitioner and exercise scientist, and was only 34. He left behind a wife and young child. He promoted FCLO and is understood to have taken it.

—Katherine Czapp, who had been editor for the WAPF journal Wise Traditions, died in late 2016 at age 60. She died of a type of colorectal cancer, as did her husband about a year before she did. Both were understood to have been users of FCLO

—Carol Esche, a nurse and a former board member of WAPF, died in late 2016 of metastatic breast cancer. It’s not known if she took FCLO. She was 59.

—Lauren Feder Haarpaintner, the author of a book on natural pregnancy, died in late 2015 of bone cancer at age 55. She was understood to have promoted FCLO on her web site.

—Chris Decker was a gifted naturopath, who was diagnosed in 2014 with a strange abdominal cancer that was so fast and vicious that oncologists couldn’t figure out what was going on. In early 2015, she pleaded for donations on her Facebook page: “As far as the MDs are concerned, the prognosis is pretty dismal. There is however, an enormous amount that natural medicine can do, and I’m seeing two wonderful cancer specialists.

Wow.

It is rare when you have to argue about which part of this terrible supplement is the worst...the rot? The VA? The PUFA?

 

[tankasnowgod]

Note that 10k/day is considered the total maximal amount that anyone should get, even getting half this amount is associated with health risks such as osteoporosis. .

Considered by who? Based on what? It wasn't even that long ago that 25,000 IU of Vitamin A was recommended daily as part of the RDA. That still is the recommendation in a lot of countries.

Regardless, as recommendations for Vitamin A have been revised downward and intakes have followed the same trend, all sorts of health problems have been on the rise.

 

[InChristAlone]

Considered by who? Based on what? It wasn't even that long ago that 25,000 IU of Vitamin A was recommended daily as part of the RDA. That still is the recommendation in a lot of countries.

Regardless, as recommendations for Vitamin A have been revised downward and intakes have followed the same trend, all sorts of health problems have been on the rise.

"Anyone who is on the borderline for thyroid function, sometimes even 20,000 units will make their symptoms worse by suppressing their thyroid. So you just have to be very cautious and probably starting with 5,000 units and watching for allergic symptoms and checking your temperature to see if it’s inhibiting your thyroid. " Ray Peat

 

[Collden]

Considered by who? Based on what? It wasn't even that long ago that 25,000 IU of Vitamin A was recommended daily as part of the RDA. That still is the recommendation in a lot of countries.

Regardless, as recommendations for Vitamin A have been revised downward and intakes have followed the same trend, all sorts of health problems have been on the rise.

Current RDAs and ULs I got from Wiki.

The question is really what are any recommended intake levels for VA based on. I haven't found credible human evidence showing health benefits of anything higher than the bare minimum of VA intake.

When and where has the RDA for VA ever been at 25 000 IU? That would be absurd considering this amount has been shown to cause severe liver damage.

What is your source that VA intake has decreased correlating with rise in health problems?

 

[Amazoniac]

Current RDAs and ULs I got from Wiki.

The question is really what are any recommended intake levels for VA based on. I haven't found credible human evidence showing health benefits of anything higher than the bare minimum of VA intake.

When and where has the RDA for VA ever been at 25 000 IU? That would be absurd considering this amount has been shown to cause severe liver damage.

What is your source that VA intake has decreased correlating with rise in health problems?

As you know, in lab experiments they use greater doses to induce a distinguishable effect, however it gets difficult to discern as the doses are lower'd to reasonable intakes, we have to go by markers, adverse effects or something else.

The RDA is based on theoresical maintenance of liver reserves, which I find fair.

Regarding the limits, they have to be reasonable as well, otherwise someone like Grant would decrease the 'Lowest Observed Adverse Effect Level' to a few mcgs, and 'None' set in ng, the upper limit decreased further and the recommended amounts in pg.


You seem to be fixated on this 25000 IU toxicity case for poison A, yet there are reports of venom D toxicity with "as little as 4000 IU":
- Hypervitaminosis D: Report on Three Patients

Contrary to this, there are cases who took insane (single or continuous) doses of either and recover'd without issues.


Mito eats plenty of protein as part of a nutritious diet, has sugarbaby high metabolism and also sun exposes: his rate of internal consumption might be brutal, so he can get away with hospitalizing doses better than most people. If needed, he could be disposing it as fast as the guy reported on the other thread.


Where's the 1500 IU/d value from?

 

[Collden]

As you know, in lab experiments they use greater doses to induce a distinguishable effect, however it gets difficult to discern as the doses are lower'd to reasonable intakes, we have to go by markers, adverse effects or something else.

The RDA is based on theoresical maintenance of liver reserves, which I find fair.

Regarding the limits, they have to be reasonable as well, otherwise someone like Grant would decrease the 'Lowest Observed Adverse Effect Level' to a few mcgs, and 'None' set in ng, the upper limit decreased further and the recommended amounts in pg.

Its problematic to set requirements for VA because most studies that tried to experimentally induce VA deficiency in humans have failed to cause deficiency symptoms that even remotely resemble the results from animal studies. In fact most studies have had to look hard to find any adverse effects of depletion at all even after putting people for several years on zero VA diets ( Experimental Induction of Vitamin A Deficiency in Humans). So there is really no strong human evidence that Vitamin A is an essential nutrient at any level.

In Brazil the average VA intake is about 1 000 IU/day (Evaluation of the Brazilian population’s intake of antioxidant nutrients and their relation with the nutritional status) - so only a fraction of the RDA. 90% of brazilians are considered VA-deficient, yet as a nation their prevalence of "VA deficiency-related" diseases is not any greater than in developed western nations.

You seem to be fixated on this 25000 IU toxicity case for poison A, yet there are reports of venom D toxicity with "as little as 4000 IU":
- Hypervitaminosis D: Report on Three Patients

Contrary to this, there are cases who took insane (single or continuous) doses of either and recover'd without issues.

While Vitamin D toxicity can be just as bad as VA toxicity acutely, the latter is more insidious because VA can accumulate in great amounts in the liver and so you can overload on VA for years or decades before you even notice anything is wrong, meanwhile completely messing up your liver. No one ever got cirrhosis from chronically overdosing on Vitamin D.

The question is really, with such a staggering amount of evidence that VA in excess (and what is excess can cause serious health problems that may take years to become apparent due to the body's buffering capacity and for the same reason are difficult to reverse - Where is the evidence that getting more than the bare minimum of VA has any health benefits?

The 1500 IU figure (actually more like 1670 IU) is from Excessive dietary intake of vitamin A is associated with reduced bone mineral density and increased risk for hip fracture. - PubMed - NCBI where people consuming less than 1670 IU had the lowest risk of osteoporosis. But judging from the data from Brazil I'd wager that even lower intakes are enough to avoid VA-related diseases.

 

[Amazoniac]

Its problematic to set requirements for VA because most studies that tried to experimentally induce VA deficiency in humans have failed to cause deficiency symptoms that even remotely resemble the results from animal studies. In fact most studies have had to look hard to find any adverse effects of depletion at all even after putting people for several years on zero VA diets ( Experimental Induction of Vitamin A Deficiency in Humans). So there is really no strong human evidence that Vitamin A is an essential nutrient at any level.

In Brazil the average VA intake is about 1 000 IU/day (Evaluation of the Brazilian population’s intake of antioxidant nutrients and their relation with the nutritional status) - so only a fraction of the RDA. 90% of brazilians are considered VA-deficient, yet as a nation their prevalence of "VA deficiency-related" diseases is not any greater than in developed western nations.

All the classic experiments have been posted before and discussed on Grant's thread, including that review and even the case report of massive mobilization in a short period.

"All eight of Sauberlich's volunteers developed clear signs of vitamin A deficiency after ∼13 mo of consuming the depleted diet, compared with 3 of 17 subjects in the study of Hume and Krebs within about the same time. This difference reveals the well-known great variability in vitamin A reserves in the population, although one wonders why the Sauberlich volunteers all appeared to have lower reserves than most of those in Sheffield."​

How do you interpret the resolution of the consequences of deprivation after the addition of poison A?

Should we be discussing whether it's essential or not? What about glycine?
- Grant Genereux's Theory Of Vitamin A Toxicity

While Vitamin D toxicity can be just as bad as VA toxicity acutely, the latter is more insidious because VA can accumulate in great amounts in the liver and so you can overload on VA for years or decades before you even notice anything is wrong, meanwhile completely messing up your liver. No one ever got cirrhosis from chronically overdosing on Vitamin D.

The question is really, with such a staggering amount of evidence that VA in excess (and what is excess can cause serious health problems that may take years to become apparent due to the body's buffering capacity and for the same reason are difficult to reverse - Where is the evidence that getting more than the bare minimum of VA has any health benefits?

The 1500 IU figure (actually more like 1670 IU) is from Excessive dietary intake of vitamin A is associated with reduced bone mineral density and increased risk for hip fracture. - PubMed - NCBI where people consuming less than 1670 IU had the lowest risk of osteoporosis. But judging from the data from Brazil I'd wager that even lower intakes are enough to avoid VA-related diseases.

That's because venom D toxicity leads to kidney/soft tissue calcification, and the detrimental effects can be cumulative as well. There will be unique people negatively affected by low intakes just like there are for poison/"vitamin" A, but we can't rely on them for generalized recommendations (although they have to be mentioned because there could be others in a similar situation).

It does have health benefits, there are various testimonials everywhere of people improving their conditions with more.
If that guy from the report, which was a single isolated case, could mobilize and dispose it at such a high rate, why are people accumulating it to begin with?

Basing the requirement on an analysis like that is equivalent to finding out how high you can go limited by other factors involved, which of course will tend to give you low values. I don't think it's a reliable guide for optimal range, especially because the population is under different conditions and from an unimportant country.

 

[baccheion]

Vitamin A toxicity risk is minimized with vitamin D3 (+ K2 MK-4), vitamin C, and vitamin E. It wasn't even that much C required to buffer against A oxidation. ~1g IIRC.

 

[Collden]

All the classic experiments have been posted before and discussed on Grant's thread, including that review and even the case report of massive mobilization in a short period.

"All eight of Sauberlich's volunteers developed clear signs of vitamin A deficiency after ∼13 mo of consuming the depleted diet, compared with 3 of 17 subjects in the study of Hume and Krebs within about the same time. This difference reveals the well-known great variability in vitamin A reserves in the population, although one wonders why the Sauberlich volunteers all appeared to have lower reserves than most of those in Sheffield."
​

How do you interpret the resolution of the consequences of deprivation after the addition of poison A?

My point is that what they say are "clear signs of VA deficiency" is in fact nothing at all like what were described in the animal studies where they basically disintegrated from the inside out and died in less than 10 weeks. From the Sheffield study:

“A variety of tests, including clinical examination, skin biopsies, slit lamp examination of the eyes, and psychologic tests were made regularly, but the only ones which gave positive results and proved useful as criteria of deficiency were plasma level of vitamin A and the capacity for dark adaption"

And:

"Sharman (30) then studied 8 epileptic patients given a vitamin A-depleted diet for 2 years. No cases of night blindness were observed"

When the symptoms they induce are so subtle and prone to biased measurement, then any resolution of such symptoms is also questionable. The only convincing evidence is the case study of an epileptic who ate a zero VA diet for 5 and a half years and developed severe eye problems that were corrected with VA, but thats it, it then stands in contrast to Grant who has been on a zero VA-diet for as long, achieved lower serum VA levels, and still has no eye problems.

How do you interpret the fact that there are by now many modern studies where they use VA-deficient diets in mice and do not induce anything close to what was seen in the original experiments?

Comparison of Ocular Pathologies in Vitamin A–Deficient Mice and RPE65 Gene Knockout Mice - Mice were on VA-deficient diet from birth till 8 months of age, that they are even alive at this point is completely at odds with the original deficiency studies.

Vitamin A deficiency and relational memory deficit in adult mice: relationships with changes in brain retinoid signalling. - PubMed - NCBI - Mice kept on VA-deficient diet from 3 weeks of age and behavioural studies done after 36 weeks on diet.

Should we be discussing whether it's essential or not? What about glycine?
- Grant Genereux's Theory Of Vitamin A Toxicity

Its like with PUFAs. They may or may not be essential, but the animal studies done to prove it were deeply flawed, and in practice it seems almost impossible to induce a deficiency in a grown person - so we'll likely never know. What we do know for VA is that its toxic in excess, what is excessive differs greatly from person to person, and that problems related to chronic excess can develop silently for years before becoming apparent. On the other side of the scale we have literally no evidence that getting more VA than that contained in an average diet has any health benefits whatsoever, and even populations getting much less than recommended don't seem to suffer from VA deficiency problems as long as their diet is otherwise ok. The only organisation that argues the benefits of VA is curiously one whose members keep dropping like flies from cancer.

People saying taking more VA improved their health, its no different than claims about fish oil. There are thousands of stories about people curing anything from eczema to depression to OCD by taking fish oil. It could be a placebo or it could be a drug-like stress response to a toxic excess, it doesn't prove anything, and most scientific evidence goes in the direction of more VA being associated with worse health.

IMHO the main question is at what intake do the known benefits outweigh the known risks, and to me that level seems to be somewhere below the current RDA.

 

[baccheion]

My point is that what they say are "clear signs of VA deficiency" is in fact nothing at all like what were described in the animal studies where they basically disintegrated from the inside out and died in less than 10 weeks. From the Sheffield study:

“A variety of tests, including clinical examination, skin biopsies, slit lamp examination of the eyes, and psychologic tests were made regularly, but the only ones which gave positive results and proved useful as criteria of deficiency were plasma level of vitamin A and the capacity for dark adaption"

And:

"Sharman (30) then studied 8 epileptic patients given a vitamin A-depleted diet for 2 years. No cases of night blindness were observed"

When the symptoms they induce are so subtle and prone to biased measurement, then any resolution of such symptoms is also questionable. The only convincing evidence is the case study of an epileptic who ate a zero VA diet for 5 and a half years and developed severe eye problems that were corrected with VA, but thats it, it then stands in contrast to Grant who has been on a zero VA-diet for as long, achieved lower serum VA levels, and still has no eye problems.

How do you interpret the fact that there are by now many modern studies where they use VA-deficient diets in mice and do not induce anything close to what was seen in the original experiments?

Comparison of Ocular Pathologies in Vitamin A–Deficient Mice and RPE65 Gene Knockout Mice - Mice were on VA-deficient diet from birth till 8 months of age, that they are even alive at this point is completely at odds with the original deficiency studies.

Vitamin A deficiency and relational memory deficit in adult mice: relationships with changes in brain retinoid signalling. - PubMed - NCBI - Mice kept on VA-deficient diet from 3 weeks of age and behavioural studies done after 36 weeks on diet.
Its like with PUFAs. They may or may not be essential, but the animal studies done to prove it were deeply flawed, and in practice it seems almost impossible to induce a deficiency in a grown person - so we'll likely never know. What we do know for VA is that its toxic in excess, what is excessive differs greatly from person to person, and that problems related to chronic excess can develop silently for years before becoming apparent. On the other side of the scale we have literally no evidence that getting more VA than that contained in an average diet has any health benefits whatsoever, and even populations getting much less than recommended don't seem to suffer from VA deficiency problems as long as their diet is otherwise ok. The only organisation that argues the benefits of VA is curiously one whose members keep dropping like flies from cancer.

People saying taking more VA improved their health, its no different than claims about fish oil. There are thousands of stories about people curing anything from eczema to depression to OCD by taking fish oil. It could be a placebo or it could be a drug-like stress response to a toxic excess, it doesn't prove anything, and most scientific evidence goes in the direction of more VA being associated with worse health.

IMHO the main question is at what intake do the known benefits outweigh the known risks, and to me that level seems to be somewhere below the current RDA.

High concentrations are in skin and the brain. People taking higher amounts notice skin healing and less acne. On the other hand, their intake was balanced with vitamin D3 (10,000 IU D3 + 25,000 IU A as retinyl palmitate) and other nutrients. No effect of extra? There's a lab test to check serum vitamin A.

 

[InChristAlone]

I've been consuming 700 at the low end to 2,000 IUs at the top of the range since last fall, I have struggled with acne spots, but right now after a course of antibiotics I literally have not one spot on my body. I think people using A for acne are misguided. It will likely come back worse at some point when the A is trying to come out.

 

[baccheion]

I've been consuming 700 at the low end to 2,000 IUs at the top of the range since last fall, I have struggled with acne spots, but right now after a course of antibiotics I literally have not one spot on my body. I think people using A for acne are misguided. It will likely come back worse at some point when the A is trying to come out.

So there was bacterial overgrowth? What are natural antibacterials? Some of the B vitamins (at least B2), vitamin C, vitamin D (+ A + K), iodine, sulfur (eg, MSM), zinc, copper, magnesium, etc.

 

[InChristAlone]

So there was bacterial overgrowth? What are natural antibacterials? Some of the B vitamins (at least B2), vitamin C, vitamin D (+ A + K), iodine, sulfur (eg, MSM), zinc, copper, magnesium, etc.

Yeah, I definitely don't advocate for using antibiotics but if acne is bad they can help, along with good hygeine and plenty of sunlight. Managing blood sugar levels. All nutrients can help the body fight acne.

 

[Amazoniac]

My point is that what they say are "clear signs of VA deficiency" is in fact nothing at all like what were described in the animal studies where they basically disintegrated from the inside out and died in less than 10 weeks. From the Sheffield study:

“A variety of tests, including clinical examination, skin biopsies, slit lamp examination of the eyes, and psychologic tests were made regularly, but the only ones which gave positive results and proved useful as criteria of deficiency were plasma level of vitamin A and the capacity for dark adaption"

And:

"Sharman (30) then studied 8 epileptic patients given a vitamin A-depleted diet for 2 years. No cases of night blindness were observed"

When the symptoms they induce are so subtle and prone to biased measurement, then any resolution of such symptoms is also questionable. The only convincing evidence is the case study of an epileptic who ate a zero VA diet for 5 and a half years and developed severe eye problems that were corrected with VA, but thats it, it then stands in contrast to Grant who has been on a zero VA-diet for as long, achieved lower serum VA levels, and still has no eye problems.

How do you interpret the fact that there are by now many modern studies where they use VA-deficient diets in mice and do not induce anything close to what was seen in the original experiments?

Comparison of Ocular Pathologies in Vitamin A–Deficient Mice and RPE65 Gene Knockout Mice - Mice were on VA-deficient diet from birth till 8 months of age, that they are even alive at this point is completely at odds with the original deficiency studies.

Vitamin A deficiency and relational memory deficit in adult mice: relationships with changes in brain retinoid signalling. - PubMed - NCBI - Mice kept on VA-deficient diet from 3 weeks of age and behavioural studies done after 36 weeks on diet.
Its like with PUFAs. They may or may not be essential, but the animal studies done to prove it were deeply flawed, and in practice it seems almost impossible to induce a deficiency in a grown person - so we'll likely never know. What we do know for VA is that its toxic in excess, what is excessive differs greatly from person to person, and that problems related to chronic excess can develop silently for years before becoming apparent. On the other side of the scale we have literally no evidence that getting more VA than that contained in an average diet has any health benefits whatsoever, and even populations getting much less than recommended don't seem to suffer from VA deficiency problems as long as their diet is otherwise ok. The only organisation that argues the benefits of VA is curiously one whose members keep dropping like flies from cancer.

People saying taking more VA improved their health, its no different than claims about fish oil. There are thousands of stories about people curing anything from eczema to depression to OCD by taking fish oil. It could be a placebo or it could be a drug-like stress response to a toxic excess, it doesn't prove anything, and most scientific evidence goes in the direction of more VA being associated with worse health.

IMHO the main question is at what intake do the known benefits outweigh the known risks, and to me that level seems to be somewhere below the current RDA.

I remember reading in one of your posts that you is pursuing a PhD degree or something like that, right? You must know then that it's sensible, polite and depending on the context almost mandatory to review what has been discussed so far before making contributions, out of respect for people's time and effort on a topic.

I don't mean to be a moralistic douche bag, but if you arrive later on a controversial discussion, especially because it's all mostly concentrated in one place, it isn't too troublesome for you skim through it or at least search for key terms prior to posting if you want to make original contributions or avoid being the person who restarts the thread every 50 pages, discouraging the next one from reading it for making it seem denser than it is. But since you've joined when it was more than 200 pages, I don't know how you assume that these elementary questionings haven't been brought up at any point.

If you did try to find, you would know that the idea of excessive storage in cases that are benefiting from restriction is as implausible as Trabis' reappearance tomorrow. When adding small amounts after a while, people that have been restricting tend to feel good and crash afterwards: a tiny amount after such a long time isn't enough to overwhelm the storage capacity, and it's very likely that such dose is not even stored, but utilized right away.

Another point that you would also know is that mice isn't a great model for storage, they is remarkable in this aspect.

- Grant Genereux's Theory Of Vitamin A Toxicity
- Grant Genereux's Theory Of Vitamin A Toxicity
- Grant Genereux's Theory Of Vitamin A Toxicity​

Not only that, but you would know as well how difficult it is to prevent them from recovering it through crap or possibly fur. The unethical wired floor is far from sufficient in preventing this, and sometimes not even a bucket attach'd to their butt is enough.

- Grant Genereux's Theory Of Vitamin A Toxicity​

Frank depletion takes a long time but it's preceded by detectable abnormalities, yet these resolve with the addition of this toxin regardless of sparing nutrients. I doubt that you can reach a critical state with moderate restriction, but we don't know if there's a price in having to conserve it during scarcity, certain functions must be prioritized over others, this is very likely.
Its disposal slows down as you approach depletion, why is that? Depots that are too rooted?


Times are different now, people are bombarded with environmental insults from everywhere, so it isn't surprising if our ability to utilize this toxin is compromised, therefore forcing us to reduce our consumption. On the other hand, our needs must be now higher than ever, and up until you can metabolize it properly, the optimal intake should be elevated since the environment demands more (of all nutrients). So what's dictating how much is ideal to consume is not the environmental demand, but the state of our body.
- <Kartoffel's long-await'd experiment on the antiestrogenic effect of poison A>


Ironically, someone gave the same fish oil/essential fatty acid example as you above and there were follow-up comments, search for it.


The double standard is odd. We have plenty of glycine, calcium, and so on, in the body. Let's say that someone consumed one of them and felt great, it's intuitive to attribute the beneficial effect to correction of an insufficiency. Now when someone takes some poison A and feels better, there you're telling them: hold on, not so fast, in this case it must be hormesis; there's a Swedish analysis on fractures that found out that people with the least fractures were those taking less than 1700 IU, which is the highest that you should go regardless of your nutritional state, gender, size, history; anything beyond that appearing to be beneficial is probably from stress.

And by the way, while we are narrowed to how much is needed for survival, even its temporary excess has therapeutic value. It's one more aspect that you would know if you had read it. Check out the many giants that agree on this:
- Grant Genereux's Theory Of Vitamin A Toxicity

 

[LeeLemonoil]

I've been consuming 700 at the low end to 2,000 IUs at the top of the range since last fall, I have struggled with acne spots, but right now after a course of antibiotics I literally have not one spot on my body. I think people using A for acne are misguided. It will likely come back worse at some point when the A is trying to come out.

No disrespect, but this kind of pure speculation on a very delicate and hypercomplex topic is not helpful.

 

[LeeLemonoil]

No disrespect, but this kind of pure speculation on a very delicate and hypercomplex topic is not helpful.

and regarding Vit. A and Acne, there is a very recent new (as in, really not known before) discovery about Vit As role in skin antibiotical physiology:

Newly identified bacteria-killing protein needs vitamin A to work


People who have inadequate vitamin A in their diets are more susceptible to skin infection, yet how that vitamin affects skin immunity has been unclear. In a study published today, UT Southwestern researchers shed some light on that mystery by identifying a previously unknown bacteria-killing protein on the epidermis that requires the vitamin to work.

The researchers found that one protein in the resistin-like molecule (RELM) family -- RELMα -- acts as an antibiotic to rapidly kill bacteria. Both RELMα, which is made by mice, and the corresponding human RELM family protein, called resistin, are stimulated by dietary vitamin A.

"RELMα is the first example of an antimicrobial protein that requires dietary vitamin A for its bacterial killing activity. This finding gives us an important clue about how the skin defends itself against infection, and how skin defense is regulated by the diet," said Dr. Lora Hooper, Chair of Immunology and corresponding author on the study published in Cell Host & Microbe.

Dermatologists use synthetic vitamin A, called retinoid, to treat acne, psoriasis, and other skin conditions, although how those drugs work has long been a mystery.

"The skin is the largest organ of the human body and is tasked with defending us against infection," said Dr. Tamia Harris-Tryon, Assistant Professor of Dermatology and Immunology.

"If the skin immune system breaks down, infection results. Skin infections, from bacteria such as Streptococcus, are among the most common reasons people come to the emergency room," added Dr. Harris-Tryon, a physician-scientist who completed postdoctoral training in the Hooper lab.

Dr. Hooper is well known for her research on the commensal or "good" bacteria that inhabit the gut -- where they aid in digestion and infection control.

The team's experiments in human tissue and mice illuminate a previously unappreciated link between diet and innate immunity of the skin, suggesting why vitamin A derivatives are effective treatments for skin disease, said Dr. Hooper, a Howard Hughes Medical Institute Investigator who is also a UTSW Professor of Immunology and Microbiology with an additional appointment in the Center for the Genetics of Host Defense. Dr. Hooper holds the Jonathan W. Uhr, M.D. Distinguished Chair in Immunology and is a Nancy Cain and Jeffrey A. Marcus Scholar in Medical Research, in Honor of Dr. Bill S. Vowell.

In addition to identifying RELMα's unique feature -- its requirement for dietary vitamin A to kill bacteria -- the team showed that mice fed a diet deficient in vitamin A made no RELMα. The researchers also found that mice missing RELMα were more susceptible to infection and had different bacterial species on their skin compared with typical mice.

Dr. Harris-Tryon added, "Considering how often retinoids are used in dermatology, the implications of our findings are potentially vast. The skin is an important interface between us and the environment and must defend us against infection and inflammation. We are just beginning to understand how bacteria and the microbiome (the term for the population of bacteria living with us) impact skin diseases such as psoriasis and acne. Our work helps to define the molecules that the skin uses to create a healthy relationship between the microbiome and us, the hosts."

To study how the microbiome impacts immunity, the researchers used Dr. Hooper's colony of germ-free mice -- mice raised from birth without exposure to germs -- and identified genes that are turned on when such mice are exposed to bacteria.

"When the skin encounters bacteria, cells respond by making molecules that help defend the skin against infection," she explained, adding that scientists at the National Institutes of Health (NIH) collaborated on the study.

The researchers included some caveats.

"This study gives us a better understanding of how diet impacts the ability of the skin to defend itself against bacterial infection -- but more research will be needed to determine how these findings will impact patients with inflammatory skin diseases such as acne and psoriasis," said Dr. Harris-Tryon, who earned her M.D.-Ph.D. at Johns Hopkins University.

Dr. Hooper's research is supported by the NIH, The Welch Foundation, and the Howard Hughes Medical Institute. Dr. Harris-Tryon received a Dermatology Foundation Career Development Award, a Burroughs Wellcome Fund Career Award for Medical Scientists, and UT Southwestern Disease-Oriented Clinical Scholars Program funding.

 

[LeeLemonoil]

Vitamin A deficiency is detrimental to blood stem cells


Retinoic acid may improve immune response against melanoma

 

[InChristAlone]

No disrespect, but this kind of pure speculation on a very delicate and hypercomplex topic is not helpful.

I'm sorry you feel it was purely speculation. For reference I used to eat liver, take retinyl palmitate every now and then and did the OJ and milk. My acne was not cured. Topical may be a little different, but I personally would never use retinoic acid on my face. Why would I? I am mostly acne free, and still had pretty darn good skin before the course of antibiotics. Now I never suffered from cystic acne, but we did have one young lady on here with cystic acne and vitamin A NEVER solved her problems. I felt so bad for her as she felt disfigured by it. We can cite studies all damn day, I get a little sick of science, you can have two completely different results based on the bias of the researcher. Researchers have been charged with fraud because they have skewed results in their favor. Ray Peat says: "perceive , think , act". My n=1 is I don't need liver or vitamin A supps or face creams to have good skin.

 

[managing]

I'm sorry you feel it was purely speculation. For reference I used to eat liver, take retinyl palmitate every now and then and did the OJ and milk. My acne was not cured. Topical may be a little different, but I personally would never use retinoic acid on my face. Why would I? I am mostly acne free, and still had pretty darn good skin before the course of antibiotics. Now I never suffered from cystic acne, but we did have one young lady on here with cystic acne and vitamin A NEVER solved her problems. I felt so bad for her as she felt disfigured by it. We can cite studies all damn day, I get a little sick of science, you can have two completely different results based on the bias of the researcher. Researchers have been charged with fraud because they have skewed results in their favor. Ray Peat says: "perceive , think , act". My n=1 is I don't need liver or vitamin A supps or face creams to have good skin.

I don't have an opinion on the Vit A debate.

However, when you quote RP (Perceive. Think. Act.) in the path of advocating for n=1 over "science" . . . I think you've fundamentally misunderstood "Perceive" as well as "Think".

An (apparent) inability to interpret scientific work does not justify discarding reason. This doesn't mean that n=1 is inherently invalid. Quite the opposite. But, alone, that reasoning is so incomplete as to be worthless.