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As you can see there is fruits, vegetables, grains, dairy, meat, poultry, eggs seafood and legumes on their list. If you search for "polyunsaturated fat" in their recent published guidelines there is only 5 mentions out of 148 pages. The idea to completely remove polyunsaturated fat from the diet is a fringe position and impossible for most people because most accessible foods consumed contain a mixture of polyunsaturated, monounsaturated or saturated fat. All PUFA is "unhealthy" etc is clearly a pseudoscientific opinion not supported by nutritional science. [[User:Psychologist Guy|Psychologist Guy]] ([[User talk:Psychologist Guy|talk]]) 22:36, 7 May 2021 (UTC)
As you can see there is fruits, vegetables, grains, dairy, meat, poultry, eggs seafood and legumes on their list. If you search for "polyunsaturated fat" in their recent published guidelines there is only 5 mentions out of 148 pages. The idea to completely remove polyunsaturated fat from the diet is a fringe position and impossible for most people because most accessible foods consumed contain a mixture of polyunsaturated, monounsaturated or saturated fat. All PUFA is "unhealthy" etc is clearly a pseudoscientific opinion not supported by nutritional science. [[User:Psychologist Guy|Psychologist Guy]] ([[User talk:Psychologist Guy|talk]]) 22:36, 7 May 2021 (UTC)

: You say that "''the idea to completely remove polyunsaturated fat from the diet is a fringe position and impossible for most people because most accessible foods consumed contain a mixture of polyunsaturated, monounsaturated or saturated fat. All PUFA is "unhealthy" etc is clearly a pseudoscientific opinion not supported by nutritional science.''" I never said these things. This is a classic straw man attack: you are misrepresenting my position by deliberately widening the scope of what I said. My concern is with the high ω-6/ω-3 ratio implied by the Dietary Guidelines, and with the modern explosion in seed oil consumption in particular, not with PUFAs in general. Of course, the idea of completely removing polyunsaturated fat from the diet, and the idea that all PUFAs are unhealthy, are both stupid ideas, on both theoretical and practical grounds. I know that, you know that, and I think you know that I know that. [[User:Piedmont|Piedmont]] ([[User talk:Piedmont|talk]]) 09:58, 8 May 2021 (UTC)

Revision as of 09:58, 8 May 2021

Restriction of dietary fat and cholesterol

This section concludes "A review of reviews also confirmed that egg consumption is associated with adverse effects regarding Heart failure and type 2 diabetes.[36]". While looking at the referenced study, the conclusions section states "Recent evidence-based reviews conclude that increased egg consumption is not associated with CVD risk in the general population. More research is needed on the positive associations between egg consumption and heart failure and T2DM risk, as well as CVD risk in diabetics, before firm conclusions can be made."

I advise that this source be either replaced with one that supports the statement being made or (more ideally) the statement be revised to reflect the evidence.

I have removed that sentence. It was false information. The umbrella review suggests the opposite [1] Psychologist Guy (talk) 20:24, 26 November 2020 (UTC)[reply]

Article needs updating for 2020–2025 version

The 2020–2025 version of the Guidelines is out: https://www.dietaryguidelines.gov/sites/default/files/2021-03/Dietary_Guidelines_for_Americans-2020-2025.pdf

I am sure this article needs major updating. — Preceding unsigned comment added by 216.36.27.133 (talk) 16:51, 25 March 2021 (UTC)[reply]

I just read the 2020-2025 Guidelines. I was very disappointed to discover that they still encourage people to reduce their consumption of saturated fats in favor of vegetable oils (polyunsaturated fats). This flies in the face of the latest scientific evidence, and represents a huge lost opportunity to educate the public. Lets hope that just as the 2020-2025 Guidelines have ditched trans fats, the 2025-2030 Guidelines will ditch unhealthy polyunsaturated fats (for example, margarine) in favor of healthy saturated fats (for example, butter). Unfortunately, the ghost of long-discredited Ancel Keys continues to cast a long shadow. Piedmont (talk) 13:43, 30 April 2021 (UTC)[reply]
I understand that there will be high-quality secondary sources coming out over the next few months that will provide us with material we can use to build the "current" 2020-2025 section. I'll make some cosmetic changes in preparation for that. sbelknap (talk) 19:04, 3 May 2021 (UTC)[reply]
You are claiming that the 2020-2025 Guidelines are wrong so you are arguing from a fringe position, see WP:Fringe. Trans fats are briefly mentioned on page 44 The USDA Dietary Patterns are limited in trans fats and low in dietary cholesterol. Cholesterol and a small amount of trans fat occur naturally in some animal source foods. As of June 2018, partially hydrogenated oils (PHOs), the major source of artificial trans fat in the food supply, are no longer Generally Recognized as Safe (GRAS). Therefore, PHOs are no longer added to foods." There are small amounts of trans fat found in meat and dairy products such as butter. In regard to Polyunsaturated Fatty Acids it is not only the DGA advising their consumption. The American Heart Foundation recommends people eat Polyunsaturated Fat (PUFAS) food and cut down on Saturated Fat (SFAS) food [2] and so does the American Diabetes Association [3]. So does practically every other professional health or medical agency.
Can you be more specific on your claim that Polyunsaturated Fats (PUFAS) are "unhealthy". Or do you mean specific PUFAS (not all)? There are Polyunsaturated Fat foods that have proven to lower bad LDL and increase good HDL. There are a lot of PUFA foods out there walnuts, sunflower seeds, flax seeds, salmon, herring, corn oil, soybean oil and safflower oil. I am guessing you are saying Omega 6 Polyunsaturated Fatty Acids are "unhealthy" but not Omega 3? Or is your issue just with oxidized PUFA or the Omega-6 to Omega-3 Ratio? As far as I know the DGA are not telling people to load up on highly-processed corn oil and nothing else, they are advising a balanced diet with PUFAS from a wide range of sources including nuts, seafood, oils and seeds. In regard to Omega 6 Polyunsaturated Fatty Acids there was a recent review on this "Despite the concern that omega-6 fatty acids increase inflammation, current evidence from studies in humans does not support this view. In conclusion, these findings support current recommendations to emphasize consumption of ω-6 PUFAs as a replacement of SFAs [4]. The mainstream scientific consensus is to use PUFAS as a replacement for saturated fat foods. There is no conspiracy because you will find that the DGA, American Heart Foundation, American Diabetes Association and practically every other health agency is saying this. This is obviously a complex topic but it is clearly not accurate to describe Polyunsaturated Fats as unhealthy nor is this the place to promote conspiracy theories that the scientific consensus is wrong. Psychologist Guy (talk) 21:33, 3 May 2021 (UTC)[reply]
Fringe position? Perhaps for the last 50 years, since the purely epidemiological "7 Countries Study" - but not now. A 2017 meta analysis of randomised control trials found that "available evidence from adequately controlled randomised controlled trials (RCTs) suggest replacing saturated fatty acids with mostly n-6 PUFA is unlikely to reduce chronic heart disease (CHD) events, CHD mortality or total mortality. The suggestion of benefits reported in earlier meta-analyses is due to the inclusion of inadequately controlled trials." [5] In other words, earlier meta-analyses have given undue weight to epidemiological studies, and not enough weight to RCTs, which are the gold standard of science-based medical research. However, other meta-analyses of RCTs go further: one concludes that "advice to specifically increase n-6 PUFA intake, based on mixed n-3/n-6 RCT data, is unlikely to provide the intended benefits, and may actually increase the risks of CHD and death." [6] So, the tide is turning - but so many reputations are on the line that it is turning very, very slowly. As the old saying goes - science advances one funeral at a time. Piedmont (talk) 15:51, 7 May 2021 (UTC)[reply]

Piedmont,

The 2017 meta-analysis by Steven Hamley (a university student) is deeply flawed. It had no medical impact. The only people who have taken it seriously are a few low-carb bloggers which you can Google. It has not been mentioned anywhere else.

Did you read all of Hamley's meta analysis you linked to? Many of the RCTs that he used in his meta analysis were very old from the 1960s based on "free-living" at home. That was his objective to look at them but some of them are unreliable yet he bizarrely includes those ones in his list of adequately controlled trials . You can go and look at these 1960s trials and rip the methodology apart he admits many of them are flawed - we have come along way since the 1960s. You can see that the trials have small sample sizes.

His meta-analyses of 11 chosen "diet heart trials" categorised the following inadequately controlled trials ODHS, NDHS, LAVAT, FMHS, HDAT, and STARS (6 trials). So he dismisses those. The adequately controlled trials which he categorised were RCOT, MRCT, SDHS, MCS, and DART (5). So six he considered unreliable by his selected criteria yet when you look at his chosen 5 they are unreliable. I don't have space to go over them all but let's look at RCOT in a minute. Remember he admits that "the pooled results from all trials, including the inadequately controlled trials, suggested that replacing SFA with mostly n-6 PUFA would significantly reduce the risk of total CHD events". His issue with the other meta-analyses is his claim that they have not included the adequate controlled trials.

The first thing to say about Hamley's meta-analysis was that is was based mostly on males with pre-existing CHD so that's an obvious bias from the start we are not looking at a broad population sample. He admits this "many of the diet heart trials only included males with pre-existing CHD", this is problematic and is not representing both sexes either. His meta-analysis is flawed due cherry picked biased data like this. 8 of the 11 trials he chose were "free-living". This means the patients were living at home. Do you find that reliable? How do you know what they were really eating? 4 of Hamley's chosen "adequately controlled trials" were "free-living". No surprise really.

The first trial he used in his meta-analysis was this one from 1965 [7] titled "Corn Oil in Treatment of Ischaemic Heart Disease" which he dubs "RCOT". The trial looked at 3 groups of patients with ischaemic heart disease.

There was a control group, a group taking 80g corn oil daily and a different group taking olive oil 80g daily. Both groups were told to cut down on saturated fat foods and limit their animal protein. There is no mention what foods the patients were eating! What were they putting the oil on? The authors of the 1965 trial admit "many found the treatment burdensome: distaste, nausea, and diarrhoea were the commonest complaints. An attempt was made to assess how much oil each patient actually took, based on the number of cans issued, the amounts left in the returned cans, and the patient's own statements." This is clearly not a reliable method to obtain accurate data. The paper then lists "estimates" in a table. This is not a good way to get results. Indeed, they also obtained estimates from a "self-administered questionary". Yet Hamley includes this unreliable trial in his reliable trial list.

We can see that patients were consuming less oil as time went on. They were consuming less oil so it is likely they were eating saturated fat foods again. During 18-24 months into the trial there were only 13 patients in each group and it was estimated they were consuming 51g daily. Is 13 patients a lot? These old trials had such small sample sizes. The results found that the corn oil group suffered worse than the control or olive oil group with infarction or death occurring in 1/4 or more of the group. The conclusion was the corn-oil is not a safe food for those with ischaemic heart disease. There are so many flaws with this trial it is embarrassing. We have come along way since the 1960s with scientific controls and methodology. I have literally just shot that one down. I could easily do the same to his other chosen 4 but you get the idea. It's unlikely the patients were eating fruits and vegetables, we do not know what they were putting their oil on. Remember this trial was used by Hamley to prove "Available evidence from adequately controlled randomised controlled trials suggest replacing SFA with mostly n-6 PUFA is unlikely to reduce CHD events, CHD mortality or total mortality". It has done no such thing. It's always best to read more than just an abstract conclusion. The Hamley meta-analysis does not hold up under scrutiny. Psychologist Guy (talk) 22:24, 7 May 2021 (UTC)[reply]

I would also point out the obvious that The Dietary Guidelines for Americans are advising a balanced diet.

The core elements that make up a healthy dietary pattern include:

  • Vegetables of all types—dark green; red and orange; beans, peas, and lentils; starchy; and other vegetables
  • Fruits, especially whole fruit
  • Grains, at least half of which are whole grain
  • Dairy, including fat-free or low-fat milk, yogurt, and cheese, and/or lactose-free versions and fortified soy beverages and yogurt as alternatives
  • Protein foods, including lean meats, poultry, and eggs; seafood; beans, peas, and lentils; and nuts, seeds, and soy products
  • Oils, including vegetable oils and oils in food, such as seafood and nuts

Dietary Guidelines for Americans 2020-2025. p. 18

As you can see there is fruits, vegetables, grains, dairy, meat, poultry, eggs seafood and legumes on their list. If you search for "polyunsaturated fat" in their recent published guidelines there is only 5 mentions out of 148 pages. The idea to completely remove polyunsaturated fat from the diet is a fringe position and impossible for most people because most accessible foods consumed contain a mixture of polyunsaturated, monounsaturated or saturated fat. All PUFA is "unhealthy" etc is clearly a pseudoscientific opinion not supported by nutritional science. Psychologist Guy (talk) 22:36, 7 May 2021 (UTC)[reply]

You say that "the idea to completely remove polyunsaturated fat from the diet is a fringe position and impossible for most people because most accessible foods consumed contain a mixture of polyunsaturated, monounsaturated or saturated fat. All PUFA is "unhealthy" etc is clearly a pseudoscientific opinion not supported by nutritional science." I never said these things. This is a classic straw man attack: you are misrepresenting my position by deliberately widening the scope of what I said. My concern is with the high ω-6/ω-3 ratio implied by the Dietary Guidelines, and with the modern explosion in seed oil consumption in particular, not with PUFAs in general. Of course, the idea of completely removing polyunsaturated fat from the diet, and the idea that all PUFAs are unhealthy, are both stupid ideas, on both theoretical and practical grounds. I know that, you know that, and I think you know that I know that. Piedmont (talk) 09:58, 8 May 2021 (UTC)[reply]
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