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  #16   ^
Old Fri, Dec-14-18, 12:02
Meme#1's Avatar
Meme#1 Meme#1 is offline
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Quote:
Originally Posted by teaser
deadly if it comes from red meat or eggs. There.


Thanks Teaser but,
Wait, what, why??

Last edited by Meme#1 : Fri, Dec-14-18 at 12:18.
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  #17   ^
Old Fri, Dec-14-18, 12:38
teaser's Avatar
teaser teaser is offline
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Plan: mostly milkfat
Stats: 190/152.4/154 Male 67inches
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Location: Ontario
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Cognitive bias? Researchers go into it thinking beef is bad. If they do a study designed to show that TMAO causes bad stuff, and it instead causes good stuff--instead of saying TMAO from beef might not be a bad thing, they say a beefy diet doesn't raise TMAO levels enough.

As to why TMAO might be bad, here's an example;

Quote:
Abstract
Several studies have reported a strong association between high plasma level of trimethylamine N-oxide (TMAO) and atherosclerosis development. However, the exact mechanism underlying this correlation is unknown. In the present study, we try to explore the impact of TMAO on endothelial dysfunction. After TMAO treatment, human umbilical vein endothelial cells (HUVECs) showed significant impairment in cellular proliferation and HUVECs-extracellular matrix (ECM) adhesion compared with control. Likewise, TMAO markedly suppressed HUVECs migration in transwell migration assay and wound healing assay. In addition, we found TMAO up-regulated vascular cell adhesion molecule-1 (VCAM-1) expression, promoted monocyte adherence, activated protein kinase C (PKC) and p-NF-κB. Interestingly, TMAO-stimulated VCAM-1 expression and monocyte adherence were diminished by PKC inhibitor. These results demonstrate that TMAO promotes early pathological process of atherosclerosis by accelerating endothelial dysfunction, including decreasing endothelial self-repair and increasing monocyte adhesion. Furthermore, TMAO-induced monocyte adhesion is partly attributable to activation of PKC/NF-κB/VCAM-1.




I think this part;

Quote:
These results demonstrate that TMAO promotes early pathological process of atherosclerosis by accelerating endothelial dysfunction, including decreasing endothelial self-repair and increasing monocyte adhesion.


is a bit irresponsible. We have to accept that human umbilical vein endothelial cells in a petri dish or somesuch are a good model for arterial endothelial cells in an intact human. At most this suggests a way in which TMAO might etc., rather than demonstrate that it does.


https://www.ncbi.nlm.nih.gov/pmc/articles/PMC3650111/


Quote:
Intestinal microbiota metabolism of L-carnitine, a nutrient in red meat, promotes atherosclerosis


This one does show an increase in atherosclerosis, in apoE deficient mice, when fed carnitine. I haven't read it very carefully, I don't know how tightly this was connected to production of TMAO as such. This paper suggests that production of TMAO by bacteria somehow reduces reverse transport of cholesterol to the liver.

Which explains why I went with the flippant answer. This stuff gets involved, and I haven't fully involved myself with it yet.
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  #18   ^
Old Fri, Dec-14-18, 12:40
teaser's Avatar
teaser teaser is offline
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Plan: mostly milkfat
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Of course a total lack of correlation of the real TMAO boosting food--fish--with heart disease, outside of probably fish and chips cohorts, throws the whole question of worrying about TMAO as such into question, although contribution of having the "wrong" gut biome seems like an interesting avenue.
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  #19   ^
Old Fri, Dec-14-18, 12:55
Ms Arielle's Avatar
Ms Arielle Ms Arielle is offline
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Plan: atkins
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Quote:
Originally Posted by doreen T
TMAO = Too Many Asinine Opinions



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  #20   ^
Old Fri, Dec-14-18, 13:18
Meme#1's Avatar
Meme#1 Meme#1 is offline
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Plan: Atkins DANDR
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Right, they're probably eating fish, chips and beer.....
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  #21   ^
Old Wed, Jan-02-19, 08:31
WereBear's Avatar
WereBear WereBear is offline
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Plan: Epi-Paleo/IF
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Quote:
Originally Posted by teaser
It's a substance that gut bacteria can produce from some nutrients like choline and l-carnitine. It's beneficial if it comes from fish or bean sprouts, deadly if it comes from red meat or eggs. There. You're up to speed.


I do wonder if that red meat bias turns up because of the high consumption of fast food hamburgers in the daily diet of so many? They code that as "red meat" though it should be categorized as "carbs."
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  #22   ^
Old Wed, Jan-02-19, 13:49
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bevangel bevangel is offline
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Plan: modified adkins (sort of)
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Quote:
WereBear wrote: I do wonder if that red meat bias turns up because of the high consumption of fast food hamburgers in the daily diet of so many? They code that as "red meat" though it should be categorized as "carbs."


I've been wondering about that same thing for a long time now...especially when you consider that most people who eat a fast food burger also have french fries and, very often, a sugar laden soft drink to go with it! Add it all up and the calories from carbs far outweigh the ones from the red meat... yet it's the red meat that gets vilified.

Reminds me of a food survey that I did a year or so back that was supposed to provide me with feedback about how "healthy" my diet was and how I could alter it to be more healthy.

The survey was about 40 questions long, each question consisting of pictures of three "meal choices" and requiring you to pick which of the three meals best depicted what you would "generally" choose to eat. "None of the above" was not an option.

Some questions showed various breakfast options, some clearly lunch options, and others were dinner meals... and many of the images presented showed up in multiple questions, paired against different alternatives.

In every question set, one of the pictures displayed a fully plant-based meal, and included "healthy whole grains" and lots of colorful fruit or vegetables. If a dessert was shown, it was always fresh fruit or a small cookie.

The second image typically included protein from fish/chicken/eggs or cheese...with plenty of green vegetables or salads as side as well as either brown rice or a "healthy whole grain" bread of some sort. If dessert was shown, it was usually fruit-based, like apple pie or cobbler.

The third image invariably showed either a very typical fast food meal (hamburger and fries/ pizza/ batter fried chicken) or red meat. Breakfast and lunch images in this category showed bacon and sausage or processed meat sandwiches. Funny thing was that EVERY single one of these third images also included a large helping of a starchy white carb as a side (French fries, a huge baked potato, a big bowl of white pasta, potato or corn chips, grits) PLUS a serving of white bread. Many also included a sugary dessert such as pecan pie!

In other words, if one wanted to choose red meat, one had to choose a whole plethora of things that that I absolutely would not eat.

Since very few of the meals pictured actually showed a meal that did not include a bunch of carbage, out of curiosity, I decided to just make random choices. Result? I was told that I needed to eat less red meat and avoid eating so much fast food... that if I replaced some or all of my red meat meals with protein from fish or chicken or from vegetarian sources, I'd be a lot healthier and could expect to live longer! Not a word about staying away from the sugary desserts or the starchy carbs.

As I recall, the survey was sent to me by my health insurance company. Thankfully, it was a self-grading thing. If I'd been required to send it back in, I'd have selected mostly vegetarian meals with a few chicken and fish meals thrown in to make my answers reasonably believable.
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  #23   ^
Old Wed, Mar-20-19, 08:28
teaser's Avatar
teaser teaser is offline
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Plan: mostly milkfat
Stats: 190/152.4/154 Male 67inches
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More TMAO... posting here because even though they show great restraint by not mentioning red meat, just saying TMAO can trigger some people when it comes to red meat...

https://www.sciencedaily.com/releas...90319163527.htm

Quote:
Fountain of youth for heart health may lie in the gut
Age-related changes to microbiome fuel vascular decline, new study shows

Why do blood vessels naturally stiffen and degrade as we age, boosting cardiovascular disease risk? New University of Colorado Boulder research has identified a surprising new culprit -- and it lives in your gut.

"This is the first study to show that changes in the gut microbiome with aging have an adverse impact on vascular health," said lead author Vienna Brunt, a postdoctoral researcher in the Department of Integrative Physiology. "It opens up a whole new avenue of potential interventions to prevent cardiovascular disease."

For the study, published in the Journal of Physiology, researchers gave young mice and old mice broad-spectrum antibiotics to kill off the majority of bacteria living in their gut, aka their gut microbiome. Then they assessed the health of their vascular endothelium (the inner lining of their blood vessels) and the stiffness of their large arteries.

They also measured blood levels of inflammatory compounds, tissue-damaging free-radicals, antioxidants and the blood-vessel-expanding compound nitric oxide in both groups.

After three to four weeks of the treatment, the young mice saw no change in vascular health. The old mice, however, saw vast improvements on all measures.

"When you suppressed the microbiome of the old mice, their vascular health was restored to that of young mice," said senior author and professor Doug Seals, director of the Integrative Physiology of Aging Laboratory. "This suggests there is something about those microorganisms that is causing vascular dysfunction."

To assess what that something may be, the researchers then took fecal samples from another set of mice and had them genetically sequenced, comparing the gut bacteria living in the old mice with that in the young.

"In general, in the old mice, we saw an increased prevalence of microbes that are pro-inflammatory and have been previously associated with diseases," Brunt said.

For instance, the old mice hosted significantly more Proteobacteria, a phyla that includes Salmonella and other pathogens, and pro-inflammatory Desulfovibrio.

To drill down further, the researchers measured blood levels of metabolites -- small molecules produced by the gut microorganisms and absorbed into the bloodstream -- in old and young mice.

Old mice had three times as much TMAO (trimethylamine N-oxide), a metabolite shown in previous studies to be linked to increased risk of atherosclerosis, heart attack and stroke.

As early as 45, risk of cardiovascular disease begins to creep up, according to the American Heart Association. By age 60-79, 70 percent of people in the United States have it. After age 80, fewer than one in five are free of it.

But just what causes healthy arteries to stiffen and lose function with age has remained somewhat of a medical mystery.

"We have long known that oxidative stress and inflammation are involved in making arteries unhealthy over time, but we didn't know why arteries begin to get inflamed and stressed. Something is triggering this," Seals said. "We now suspect that, with age, the gut microbiota begins producing toxic molecules, including TMAO, which get into the blood stream, cause inflammation and oxidative stress and damage tissue."

Seals and Brunt stress that they are absolutely not suggesting people use antibiotics as a cardiovascular fountain of youth.

"We purely used antibiotics as an experimental tool. There are far too many side-effects and other problems with using it broadly," Brunt said.

But they do believe that diets high in probiotic-rich cultured food (yogurt, kefir, kimchi) and prebiotic fiber could play a role in preventing heart disease by promoting a healthy gut microbiome.

They're also studying a compound called dimethyl butanol, found in some olive oils, vinegars and red wines, which blocks the bacterial enzyme required to produce TMAO. Ultimately, it could be developed into a dietary supplement.

Bigger picture, the paper -- along with studies linking an aging microbiome to gastrointestinal, immune and brain aging -- offers one more reason to keep our resident bacteria healthy, notes an editorial accompanying the journal article.

As its authors put it:

"The fountain of youth may actually lie in the gut."


TMAO seems significant--because we've noticed it. There's a difference between a gut biome that happens to increase TMAO causing heart disease and TMAO causing heart disease.
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  #24   ^
Old Wed, Mar-20-19, 11:32
WereBear's Avatar
WereBear WereBear is offline
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Plan: Epi-Paleo/IF
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My new (mid-January) diet is very low carb, and consists mostly of RED MEAT.

It was nice knowing ya'll... because it's really helping with sleep, my autoimmune issues, and energy. But headlines tell me what I'm doing is like gargling cyanide while juggling chainsaws, so of course I must believe them instead of "my lyin' eyes".
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  #25   ^
Old Wed, Mar-20-19, 11:55
Meme#1's Avatar
Meme#1 Meme#1 is offline
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Plan: Atkins DANDR
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Quote:
Originally Posted by WereBear
My new (mid-January) diet is very low carb, and consists mostly of RED MEAT.

It was nice knowing ya'll... because it's really helping with sleep, my autoimmune issues, and energy. But headlines tell me what I'm doing is like gargling cyanide while juggling chainsaws, so of course I must believe them instead of "my lyin' eyes".


I was just telling a friend that meat is 100% digestible!
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  #26   ^
Old Wed, Mar-20-19, 12:15
WereBear's Avatar
WereBear WereBear is offline
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Plan: Epi-Paleo/IF
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Quote:
Originally Posted by Meme#1
I was just telling a friend that meat is 100% digestible!


My tum has not lodged any complaints. I am also taking in very little fiber, which also pleases my guts.

I even dodged that awful virus that was going around, which so upset people's systems they didn't eat for a week.
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  #27   ^
Old Mon, Jul-22-19, 13:19
teaser's Avatar
teaser teaser is offline
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Plan: mostly milkfat
Stats: 190/152.4/154 Male 67inches
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Quote:
Heart disease biomarker linked to paleo diet


I saw this headline, went, oh crud, it's going to be TMAO again.

Quote:
People who follow the paleo diet have twice the amount of a key blood biomarker linked closely to heart disease, the world's first major study examining the impact of the diet on gut bacteria has found.

Researchers from Edith Cowan University (ECU) compared 44 people on the diet with 47 following a traditional Australian diet.

The research, published in the European Journal of Nutrition, measured the amount of trimethylamine-n-oxide (TMAO) in participants' blood.

High levels of TMAO, an organic compound produced in the gut, are associated with an increased risk of heart disease, which kills one Australian every 12 minutes.

Impact on gut health

The controversial Paleo (or 'caveman') diet advocates eating meat, vegetables, nuts and limited fruit, and excludes grains, legumes, dairy, salt, refined sugar and processed oils.

Lead researcher Dr Angela Genoni said that with the diet's growing popularity, it was important to understand the impact it could have on overall health.

"Many Paleo diet proponents claim the diet is beneficial to gut health, but this research suggests that when it comes to the production of TMAO in the gut, the Paleo diet could be having an adverse impact in terms of heart health," she said.

"We also found that populations of beneficial bacterial species were lower in the Paleolithic groups, associated with the reduced carbohydrate intake, which may have consequences for other chronic diseases over the long term."

Reduced intake of whole grains to blame

She said the reason TMAO was so elevated in people on the Paleo diet appeared to be the lack of whole grains in their diet.

"We found the lack of whole grains were associated with TMAO levels, which may provide a link between the reduced risks of cardiovascular disease we see in populations with high intakes of whole grains," she said.

The researchers also found higher concentrations of the bacteria that produces TMAO in the Paleo group.

"The Paleo diet excludes all grains and we know that whole grains are a fantastic source of resistant starch and many other fermentable fibres that are vital to the health of your gut microbiome," Dr Genoni said.

"Because TMAO is produced in the gut, a lack of whole grains might change the populations of bacteria enough to enable higher production of this compound.

"Additionally, the Paleo diet includes greater servings per day of red meat, which provides the precursor compounds to produce TMAO, and Paleo followers consumed twice the recommended level of saturated fats, which is cause for concern.

Dr Angela Genoni initially presented her findings at the Nutrition Society of Australia Conference last year. This is the first time the findings have been published in a peer-reviewed journal.



Quote:
Researchers from Edith Cowan University (ECU) compared 44 people on the diet with 47 following a traditional Australian diet.


Lol at the current Australian diet being called traditional.

Saw a quote recently about how targeting a disease marker can make it cease to be a marker. Association of diet with TMAO hasn't proven TMAO to be a worthy target for disease prevention thus far. I'm certainly not going to be avoiding dietary choline or carnitine without much better evidence than I've seen so far.

Conclusions to the abstract;

Quote:
Conclusions
Although the PD is promoted for improved gut health, results indicate long-term adherence is associated with different gut microbiota and increased TMAO. A variety of fiber components, including whole grain sources may be required to maintain gut and cardiovascular health.


Yes, but were their guts healthy? TMAO is not an unhealthy gut.

https://www.sciencedaily.com/releas...90722105935.htm
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  #28   ^
Old Mon, Jul-22-19, 17:41
GRB5111's Avatar
GRB5111 GRB5111 is offline
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Plan: Ketogenic (LCHFKD)
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Quote:
"Additionally, the Paleo diet includes greater servings per day of red meat, which provides the precursor compounds to produce TMAO, and Paleo followers consumed twice the recommended level of saturated fats, which is cause for concern.

Dr Angela Genoni initially presented her findings at the Nutrition Society of Australia Conference last year. This is the first time the findings have been published in a peer-reviewed journal.

So, what did these Paleolithic subjects do to be selected and how strict was the Paleo regimen?

Here's the detailed study:
https://www.sciencedaily.com/releas...90722105935.htm
Quote:
Participants

Recruitment for the study took place between August 2016 and June 2017 through online advertisements. Primary inclusion criteria for the Paleolithic diet group were adherence to the dietary pattern for > 1 year period and consumption of no more than 1 serve/day of grains and dairy products. For inclusion in the control group, participants needed to have made no changes to their diet in the previous year, and follow a relatively healthy diet which included grains, legumes and dairy or alternatives. Specific inclusion criteria for both groups were: men and women aged 18Ė70 years; willingness to complete a 3-day weighed diet records (3d WDR), provide blood, urine and stool samples; non-smoker, not participating in other studies and had BMI < 30 kg/m2. Subjects were excluded if they had taken antibiotics in the previous 6-month, had a past or present digestive disorder, surgery on the gastrointestinal tract, used anti-hypertensive or lipid or glucose-lowering medication, previous cardiovascular events or diagnosed CVD. Participants were screened via email or phone confirming exclusion/inclusion criteria were met and provided written informed consent prior to study commencement. Participants completed a diet history interview, followed by a 3d WDR, including 2 week days and 1 weekend day. Samples collected were a 24-h urine and fasted (overnight) blood sample. Portable freezers (Waeco-CF-40,Dometic, Australia) were supplied to collect all stool samples over a 48-h period. Physical activity was assessed by the International Physical Activity Questionnaire.

Quote:
Conclusion

The cross-sectional data collected suggests that long-term adherence to the Paleolithic diet may not be beneficial for gut health, due to the association with lower relative abundances of known beneficial bacterial genera, and the increased relative abundance of TMA producing genera Hungatella. Our findings highlight that further research is required to understand the role of vegetables and saturated fat and how they influence colonic uptake of SCFA and subsequent excretion. The rationale to exclude whole grains is not supported by data presented here; being inversely associated with body weight and TMAO concentrations. Despite the maintenance of SCFA excretion, and stool frequency and form, the differences noted in microbiota composition associated with the high fat and low carbohydrate intake may not be beneficial for long-term health.

My addition of bolded words.

Interesting, and a reliance on good faith and questionnaires prevents any strong conclusions. It is assumed that the elimination or strict limitation of whole grains appears to be the cause targeted here. I appreciate the fact that the authors acknowledge the need for further research. This is a complex topic and association is the best that can be said at this time. Whole grains will feed the world.

Edited to add: Here's another basic explanation of TMAO and its purported role in humans:
https://www.mygenefood.com/tmao-hea...ease-know-dont/

Quote:
So what to do about TMAO?

Well to me it is clear that it has a role in various diseases when present at high levels. But it is also clear that there is a huge level of variation in peoples responses. We donít currently have a good handle on whatís causing that variation so the best advice for now would be to check your own levels, and then make a decision based on those in conjunction with your healthcare provider.

Last edited by GRB5111 : Mon, Jul-22-19 at 17:47.
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  #29   ^
Old Mon, Jul-22-19, 17:52
Dodger's Avatar
Dodger Dodger is online now
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Plan: Paleoish/Keto
Stats: 225/170/175 Male 71.5 inches
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Location: Longmont, Colorado
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I've been eating red meat in almost every meal for the last 17 years. My blood chemistry was horrible before I switched to low-carb from low-fat (also low-red meat). My tests last month were all great. Of course, my TMAO levels were not measured and my gut bacteria were not examined so I could be almost dead and not know it.
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  #30   ^
Old Mon, Jul-22-19, 17:58
teaser's Avatar
teaser teaser is offline
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Plan: mostly milkfat
Stats: 190/152.4/154 Male 67inches
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I don't personally worry about my fermentable fiber and reverse starch intake one way or another. But as far as paleo goes--there are much richer sources for both of these, non-grain sources that are both arguably paleo, and much lower in digestible carbohydrate.

My gut bacteria can give a shot at fermenting palmitic acid, for all I care.
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