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  #1   ^
Old Fri, Mar-30-18, 11:42
teaser's Avatar
teaser teaser is offline
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Default Just one high-fat meal sets the perfect stage for heart disease

https://www.sciencedaily.com/releas...80329083259.htm

Quote:
Just one high-fat meal sets the perfect stage for heart disease

A single high-fat milkshake, with a fat and calorie content similar to some enticing restaurant fare, can quickly transform our healthy red blood cells into small, spiky cells that wreak havoc inside our blood vessels and help set the perfect stage for cardiovascular disease, scientists report.

Just four hours after consuming a milkshake made with whole milk, heavy whipping cream and ice cream, healthy young men also had blood vessels less able to relax and an immune response similar to one provoked by an infection, the team of Medical College of Georgia scientists report in the journal Laboratory Investigation.

While the dramatic, unhealthy shift was likely temporary in these healthy individuals, the scientists say there is a definite cumulative toll from this type of eating, and that their study could help explain isolated reports of death and/or heart attack right after eating a super-high fat meal.

"We see this hopefully as a public service to get people to think twice about eating this way," says Dr. Neal L. Weintraub, cardiologist, Georgia Research Alliance Herbert S. Kupperman Eminent Scholar in Cardiovascular Medicine and associate director of MCG's Vascular Biology Center.

"The take-home message is that your body can usually handle this if you don't do it again at the next meal and the next and the next," says Dr. Julia E. Brittain, vascular biologist at the MCG Vascular Biology Center and a corresponding author of the study.

As a practicing cardiologist, Weintraub, also a corresponding author, has patients with cardiovascular disease who continue to eat a high-fat diet and he definitely asks them to think twice: "Is this food worth your life?"

While none of the scientists recommend going overboard on calories and sugar either, the healthy males in the study who instead consumed a meal with the same number of calories but no fat -- three big bowls of sugar-coated flakes with no-fat milk -- did not experience the same harmful changes to their blood, red blood cells and blood vessels.

"You are looking at what one, high-fat meal does to blood-vessel health," says Dr. Ryan A. Harris, clinical exercise and vascular physiologist at MCG's Georgia Prevention Institute and study co-author.

Their study in 10 young men was the first to look specifically at red blood cells, the most abundant cell in our blood. Red cells are best known for carrying oxygen and are incredibly flexible so they flow through blood vessels essentially unnoticed, Brittain says. But with a single high-fat meal, they essentially grow spikes and spew poison.

"They changed size, they changed shape, they got smaller," Harris says of the rapid changes to the form and function of red blood cells.

In both the cells and blood, there was evidence of myeloperoxidase, or MPO, an enzyme expressed by a type of white blood cell which, at high levels in the blood, has been linked to stiff blood vessels, oxidative stress and heart attack in humans.

MPO is associated with impaired ability of blood vessels to dilate, even oxidation of HDL cholesterol, which converts this usually cardioprotective cholesterol into a contributor to cardiovascular disease. When taken up by a diseased artery, it can even help destabilize plaque buildup, which can result in a stroke or heart attack.

"Myeloperoxidase levels in the blood are directly implicated in heart attack," Weintraub notes. "This is a really powerful finding."

When they used flow cytometry to examine the red blood cells, they found an increase in reactive oxygen species, a natural byproduct of oxygen use that is destructive at high levels. One effect of their elevated level is permanently changing the function of proteins, including the one that helps red blood cells maintain their normal negative charge.

MPO also impacts the cytoskeleton, the physical infrastructure of the usually plump red cells so they can't function and flex as well, says Tyler W. Benson, a doctoral student in The Graduate School at Augusta University and the paper's first author.

"Again, your red blood cells are normally nice and smooth and beautiful and the cells, after consumption of a high-fat meal, get these spikes on them," says Brittain. Much like huge ice chunks do to a river, these physical changes affect how blood flows, she says.

Bad changes occur quickly in these cells, which are "exquisitely sensitive" to their environment, Brittain says.

There were changes in white blood cells, called monocytes, which got fat themselves trying to take up the excessive fat. Their earlier studies have shown these so-called foamy monocytes promote inflammation and show up in atherosclerotic plaque. Monocytes more typically travel the circulation looking for red blood cells that need elimination, because they are old and/or diseased.

The fluid portion of the blood, called the plasma, also looked different. When they spin and separate different components of the blood to get to the red blood cells, they typically get a clear yellowish plasma on top, Benson says. But after a single, high-fat load, the fluid portion of the blood was already thick, off-color and filled with lipids.

Their blood also contained the expected high fat and cholesterol levels.

At least in mice studies and in some of Brittain's other human studies, the unhealthy changes also resolve quickly, at about eight hours, unless the high-fat feasts continue. The investigators note they only tested their participants after four hours, which is about how long it takes food to digest.

Studies to measure longer-term impact on humans would be problematic primarily because you would not want to subject healthy young individuals to the risk, Weintraub notes.

However, the MCG team also has shown that mice continuously fed a high-fat diet experience permanent changes to their red blood cells and blood similar to those experienced transiently by the young men. Changes include triggering a significant immune response that can contribute to vascular disease.

More studies are needed to see if changes in the red blood cell shape impact vascular health, the scientists write. But they conjecture that the remodeled red blood cells themselves could be targeted for elimination by monocytes. In mice chronically fed a high-fat diet, they have seen red blood cells actively consumed by macrophages, immune cells that eat cellular debris, and resulting inflammation.

Weintraub says primary prevention is the most prudent course for a healthy cardiovascular system including eating healthy, exercising regularly, and keeping tabs on vitals like cholesterol and blood pressure levels. Even patients with a high genetic risk of cardiovascular disease can dramatically reduce that risk with these positive changes, he says.

Harris' research team has done studies that indicate a single aerobic exercise session by young healthy individuals like these can counteract the unhealthy slump at four hours and related reduction in the blood vessels ability to dilate.

Participants in the new study included 10 physically active men with a good medical history, taking no prescription medicines and with good cholesterol and lipid levels.

The investigators did two thorough assessments of cardiovascular disease risk at least seven days apart. Participants were told to avoid caffeine and strenuous physical activity for 24 hours before each test and vitamin supplements for 72 hours. Like going to the doctor for bloodwork, they also were asked to fast overnight.

Half the men got the milkshakes containing about 80 grams of fat and 1,000 calories. The cereal meal also contained about 1,000 calories but very little fat. Meals were individually tweaked to ensure everyone got the same amount of fat relative to their body weight, Harris says.

Since estrogen is considered cardioprotective in non-obese premenopausal females, investigators opted to limit the study to males.

Red blood cells, probably best known for carrying oxygen, are the most abundant cell type circulating in our blood. "You have 25 trillion red blood cells and they affect every other cell in your body," says Brittain. They also carry and release the energy molecule ATP and nitric oxide, which helps blood vessels relax, as well as cholesterol.

A healthy red blood cell has a negative charge that keeps them away from other cells and traveling more toward the outer edge of blood vessels. In the arterial system, they travel fast, Brittain says.

The cells last about 120 days, but like many of us, they become less efficient with age as they use up their energy, or ATP stores, says Benson.


Gosh, I hope I posted this before any of you ate any fat.

Quote:
"We see this hopefully as a public service to get people to think twice about eating this way,"


So, is this an investigation, or a demonstration? Fat is bad, we know this, here's this little "study" we did with an easily predictable outcome, in order to make the news and sway public opinion? They mention fatty diets hurting rodents long term, but the observation that there are high fat diets that don't hurt the animals isn't something to ignore. The question isn't "is fat harmful?" it's "under what conditions is fat harmful?"

I would concede that a diet of sugary milk shakes might be worse for you than a diet of sugary cereal. I concede this with heavy cream on my breath.
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  #2   ^
Old Sat, Mar-31-18, 06:43
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wyatt wyatt is online now
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Quote:
Originally Posted by teaser
https://www.sciencedaily.com/releas...80329083259.htm



Gosh, I hope I posted this before any of you ate any fat.



So, is this an investigation, or a demonstration? Fat is bad, we know this, here's this little "study" we did with an easily predictable outcome, in order to make the news and sway public opinion? They mention fatty diets hurting rodents long term, but the observation that there are high fat diets that don't hurt the animals isn't something to ignore. The question isn't "is fat harmful?" it's "under what conditions is fat harmful?"

I would concede that a diet of sugary milk shakes might be worse for you than a diet of sugary cereal. I concede this with heavy cream on my breath.


Did the grain and dairy industry fund the study is the standard go-to question, but in addition, why is there not a control group eating ribeyes with butter on top?
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  #3   ^
Old Sat, Mar-31-18, 06:46
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wyatt wyatt is online now
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  #4   ^
Old Sat, Mar-31-18, 07:21
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teaser teaser is offline
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The control I want is plain heavy cream. Also at least a week for people to adapt to eating this meal, the acute response to a food depends to large degree on habitual diet.

It's mentioned that these short term effects on red blood cells are mirrored in rodents on high fat diets long term. Well, the sort of fatty, sugary carby diet they're talking about is just the thing to elevate fasting triglycerides, maybe it's not surprising if that does the same thing to red blood cells as a large fat meal for somebody not accustomed to it. Jeff Volek has done some work looking at the blood triglyceride response to a similar high fat meal in people on high carb, low fat or low carb, high fat diets. In the low carb, high fat dieters, fat tolerance was much higher, blood triglycerides much lower at all time points.
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  #5   ^
Old Sat, Mar-31-18, 08:22
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cotonpal cotonpal is offline
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Quote:
Originally Posted by wyatt


Terrific talk by Nina. Thanks for the link.
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  #6   ^
Old Sat, Mar-31-18, 15:26
Bonnie OFS Bonnie OFS is offline
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Quote:
Originally Posted by wyatt
Did the grain and dairy industry fund the study is the standard go-to question, but in addition, why is there not a control group eating ribeyes with butter on top?


Let's see, today we had panna cotta made with cream - no sugar. Tomorrow is ribeye & another serving of panna cotta - different flavor (I'm experimenting ).

Somehow, I don't think the fat is going to effect me like a full-sugar milkshake would.

I guess it's reports like this that make my doctor think I should be taking a statin. No thanks. My blood sugar likes my diet. So do my taste buds. It's funny - people think my diet is restrictive. But I eat SO much better than when I was eating high carb crap.
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  #7   ^
Old Mon, Apr-02-18, 23:07
M Levac M Levac is offline
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I skimmed the paper. There's an interesting bit about free fatty acids. The LFM group saw a drop from about 109um/l to about 40um/l. Where are the FFAs going? Not in the blood, trigs stayed about the same. The FFAs must be going somewhere, I bet it's to fat tissue. In other words, that single low-fat meal made the guys fatter. Otherwise ain't nothin' to see here. The discussion paragraph says it all (parentheses and bold mine):
Quote:
RBCs (red blood cells) intimately interact with blood vessels and are increasingly recognized for their complex role in regulating vascular function and cardiovascular-related disease. Here, we demonstrate for the first time in humans (2018, the lipid hypothesis is at least 50 years old, 'bout time) that a single HFM (high-fat meal) sufficient to induce lipemia promotes RBC remodeling, induces intracellular ROS (reactive oxygen species) and oxidative damage to RBC membranes, and increases circulating and RBC-bound MPO (myeloperoxidase) that is sufficient to promote oxidative modification of HDL. Additionally, in vitro, monocytic cells exposed to lipid release MPO, which in turn is taken up by coronary arteries in the presence of free fatty acids. These findings may have implications with regard to the mechanisms, whereby consumption of meals rich in fat have been temporally linked to the development of acute coronary syndromes in humans.

If I can paraphrase. Fat is bad, it took a single milkshake to prove it. It's sciance, we are sciantists, you must believe us this time, cuz it's the truth full of acronyms and stuff.

Ima paraphrase something else. The Bellevue all-meat trial lasted one year. Two men participated. They each ate about 230g (or about 3 of those milkshakes) of fat each day of that year, spread over several meals each day, for about 1,000 meals each total. Conclusion from those sciantists doin' the sciance: No observed adverse effect.

Alright, here's how it's gonna go down for me. Either they just found out that fat is truly bad, or they just found out why the Bellevue all-meat trial didn't find nothin' bad, you know cuz of all those nasty acronyms and stuff.

Some math. In this latest sciance, there's 10 subjects, half HFM so 5 milkshakes. In the Bellevue all-meat trial, there's two subjects, total ~2,000 meals. Quick calculus, we got 400x (or 1995+, if you prefer) meals that suggest fat is benign at worse. Let me put it another way. Somebody hits something with a hammer 5 times, somebody else hits something with a hammer 2,000 times, they completely disagree on the results, we gotta decide which guy is telling the truth.
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  #8   ^
Old Thu, Apr-05-18, 19:44
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wyatt wyatt is online now
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"Either they just found out that fat is truly bad, or they just found out why the Bellevue all-meat trial didn't find nothin' bad, you know cuz of all those nasty acronyms and stuff."

Isn't it interesting how it was "them" studying us and determining what the proper (diet, drug etc. you fill in the blank) and now we study "them" as well.. Fortunately, consciousness allows us to not 'always' be the victim. There's hope.
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  #9   ^
Old Fri, Apr-06-18, 04:00
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WereBear WereBear is offline
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Quote:
Originally Posted by M Levac
Somebody hits something with a hammer 5 times, somebody else hits something with a hammer 2,000 times, they completely disagree on the results, we gotta decide which guy is telling the truth.


Not only benign results.

Quote:
No clinical evidence of vitamin or calcium deficiency was noted, despite the diet being both acidic and low in calcium. In addition, the mild gingivitis Stefansson had suffered from, cleared up entirely during the meat diet. Interestingly, Andersen reported that his hair stopped falling out shortly after the meat diet was started; Stefansson also noted his hair started growing thicker and his scalp was healthier.

Two Brave Men Who Ate Nothing But Meat for an Entire Year


If there was a pill that would produce these results, it would be as hot as Viagra

Quote:
Originally Posted by Bonnie OFS
Let's see, today we had panna cotta made with cream - no sugar. Tomorrow is ribeye & another serving of panna cotta - different flavor (I'm experimenting ).


Thank you, thank you, for bringing up panna cotta. This has set my mad scientist side into ecstasies -- what a versatile thing which combines some favorite stuff in fun ways. I even have the grass-fed gelatin!

Last edited by WereBear : Fri, Apr-06-18 at 04:11.
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  #10   ^
Old Fri, Apr-06-18, 06:21
Bonnie OFS Bonnie OFS is offline
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Quote:
Originally Posted by WereBear
Thank you, thank you, for bringing up panna cotta. This has set my mad scientist side into ecstasies -- what a versatile thing which combines some favorite stuff in fun ways. I even have the grass-fed gelatin!


I found the almond flavor needed something more - perhaps berries. I'll try that when the berries are in season - if winter ever ends. We still have snow.

But the orange extract - marvelous!

Let me know what you experiment with.
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  #11   ^
Old Fri, Apr-06-18, 06:29
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teaser teaser is offline
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I commiserate. We can still walk on the bay.
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  #12   ^
Old Tue, Apr-10-18, 08:57
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teaser teaser is offline
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Plan: mostly milkfat
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Quote:
Effects of dietary carbohydrate restriction versus low-fat diet on flow-mediated dilation.
Volek JS1, Ballard KD, Silvestre R, Judelson DA, Quann EE, Forsythe CE, Fernandez ML, Kraemer WJ.
Author information
Abstract
We previously reported that a carbohydrate-restricted diet (CRD) ameliorated many of the traditional markers associated with metabolic syndrome and cardiovascular risk compared with a low-fat diet (LFD). There remains concern how CRD affects vascular function because acute meals high in fat have been shown to impair endothelial function. Here, we extend our work and address these concerns by measuring fasting and postprandial vascular function in 40 overweight men and women with moderate hypertriacylglycerolemia who were randomly assigned to consume hypocaloric diets (approximately 1500 kcal) restricted in carbohydrate (percentage of carbohydrate-fat-protein = 12:59:28) or LFD (56:24:20). Flow-mediated dilation of the brachial artery was assessed before and after ingestion of a high-fat meal (908 kcal, 84% fat) at baseline and after 12 weeks. Compared with the LFD, the CRD resulted in a greater decrease in postprandial triacylglycerol (-47% vs -15%, P = .007), insulin (-51% vs -6%, P = .009), and lymphocyte (-12% vs -1%, P = .050) responses. Postprandial fatty acids were significantly increased by the CRD compared with the LFD (P = .033). Serum interleukin-6 increased significantly over the postprandial period; and the response was augmented in the CRD (46%) compared with the LFD (-13%) group (P = .038). After 12 weeks, peak flow-mediated dilation at 3 hours increased from 5.1% to 6.5% in the CRD group and decreased from 7.9% to 5.2% in the LFD group (P = .004). These findings show that a 12-week low-carbohydrate diet improves postprandial vascular function more than a LFD in individuals with atherogenic dyslipidemia.


https://www.ncbi.nlm.nih.gov/pubmed/19632695

Just the abstract, this is that Volek study showing less of a triglyceride response in people habituated to a low carb diet. Something that should be addressed in all milkshake of death studies (but probably won't be) going forward.
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  #13   ^
Old Tue, Apr-10-18, 11:16
M Levac M Levac is offline
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Plan: VLC, mostly meat
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So adaptation switches it around. Note how pp insulin gets cut in half for CRD (low-carb). Post-prandial insulin is special because normally the bulk gets sucked up by the liver before we can measure it at the arm. Since there was a big drop for the CRD group, it follows that the liver became very insulin sensitive.

My paradigm explains this by an increase in ketones, where ketones activate insulin receptors. There's little to no ketones in the LFD group, so there's no insulin receptor activation, hence the very small drop comparatively. Also, dietary fat activates the PPAR-a pathway in the liver, which then activates insulin-degrading enzyme, ultimately resulting in a greater capacity to degrade insulin once it hits the liver. After twelve weeks of adaptation to just these two mechanisms meal after meal, a single high-fat meal challenge is no longer a big deal.

Since it's the same high-fat meal challenge for both groups, the insulin response from the pancreas should be the same too. But since there's both a greater capacity to receive insulin by the liver and greater capacity to degrade this insulin due to 12 weeks of high-fat meals, the insulin measured at the arm has already been cut in half by the liver compare to the LFD group.

Besides dietary fat, I suspect fat-solubles, especially vitamin A since it's stored in the liver, play a central role in all this.

Forgot. Why is it more kinda sorta steady-state for the LFD group? Simple. There's always more insulin everywhere.
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  #14   ^
Old Tue, Apr-10-18, 11:41
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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Progress: 104%
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Yeah, I found a lower insulin response to the exact same meal interesting.

Insulin response to non-carbohydrate nutrients like fatty acids, amino acids and ketones is largely glucose dependent, so that's another thing. It would be interesting to see the same experiment, but looking at the effects of a lean protein meal under the two diets.
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  #15   ^
Old Wed, Apr-11-18, 18:03
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wyatt wyatt is online now
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[QUOTE=teaser]Yeah, I found a lower insulin response to the exact same meal interesting.


This article focuses mainly on a high protein (from Optimising Nutrition). If you don't know this group, the guy who runs it is an engineer whose wife has type 1 diabetes, as I remember.

https://optimisingnutrition.com/201...nse-to-protein/
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