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That goes against everything I've been told about the types of fats. How much evidence is there for this?

Take it for what it is: http://raypeat.com/articles/articles/unsaturated-oils.shtml

> When unsaturated oils are exposed to free radicals they can create chain reactions of free radicals

This seems like the most important claim and also has no citations.

I mean from an organic chemistry perspective it's obviously true. If you throw an electron at a C=C double bond, you get a ·C-C¯: which will then go ahead and bond with an H⁺ that's floating around, leaving you with a radical still bound to your initial molecule, so the theory is

    CH₃-CH=CH-CH₃ + · + ROH ⇒ CH₃-ĊH-CH₂-CH₃ + :O¯R
    CH₃-ĊH-CH₂-CH₃ + HOR' ⇒ CH₃-CH₂-CH₂-CH₃ + ·OR'

and then the · on your ·OR' restarts the cycle, and the cycle doesn't stop until you get

    RO· + ·OR' ⇒ ROOR'

which is gonna be some random peroxide that wouldn't normally form, or

   CH₃-ĊH-CH₂-CH₃ + CH₃-ĊH-CH₂-CH₃ ⇒  CH₃-CH-CH₂-CH₃
                                          |
                                      CH₃-CH-CH₂-CH₃

which is gonna be some really random molecule with who knows what effects.

Now how important this is in a biological context I have no idea. There is a plausible mechanism for it to affect cellular chemistry, but the problem is that "a plausible mechanism" and "an actual effect" are very far from the same thing, and biochemistry is complicated.

The citation I'd want to see is that the chain reactions of free radicals do something biologically interesting, or, even better, that diets high and low in polyunsaturated fats lead to significant health differences in animal models.

This reads like some nutrition grifter satire.

If you don't mind, I'm going to use "nutrition grifter" moving forward.

OP here is correct. PUFAs are the baddies. This is way too large a subject for me to even try backing up atm but I do recommend you do research into it.

Or even at least a source would be nice.

> (due to being unsaturated fats and so having single hydrogen bonds that can react with other molecules inside your body).

What do you mean by "single hydrogen bonds"? C-H bonds are always single bonds, and I am unfamiliar with any kind of "double" hydrogen (intermolecular) bonding. Unsaturated fats, by definition, have at least one double bond, between carbon atoms.

Sorry, you are correct. I fixed my comment. What I meant was the carbon-carbon double bonds replace a hydrogen atom that would otherwise be there, so the bond can be easily broken when interacting with other molecules (because the carbon-carbon bond is electron rich).

Source on harmful effects of polyunsaturated fatty acids? Had trouble finding it through Google (maybe was searching for the wrong thing)

> studies of fat consumption that break out fats into saturated, mono-unsaturated, and poly-unsaturated fat categories generally show worse health outcomes for people consuming high intakes of poly-unsaturated fats. I will try to find a good study.

This is counter to any study that I am familiar with and flies in the face of all nutritional recommendations. Studies that support MUFAs and PUFAs over saturated fats can be found in the references section of https://www.hsph.harvard.edu/nutritionsource/2016/12/19/satu....

I believe this study does not control for whether the fat is hydrogenated or not. So they are really measuring the effects of trans-fats, which are already known to be bad.

That is my general concern with almost all of the nutrition research on fats. They are not grouping the fats appropriately. If you group butter and hyrogenated vegetable oils together because they are both "saturated" fats and then do your analysis lumping them together then you can't distinguish whether the problems caused by saturated fats are due to the hydrogenization or due to the butter being saturated or both.

Saturated fat consumption is decreasing, while unsaturated fat consumption is increasing, but people continue getting less healthy. So it seems the premise that saturated fats are that bad needs to be questioned. Or at least we need to ask if it's really saturated fats like coconut oil and butter that are bad or something that happens to the fats like canola oil when it is hydrogenated.

Edit: also as anecdotal evidence, what is the one common feature of almost all food generally considered harmful? Lots of processed vegetable oils in it, often in conjunction with sugar. I have not seen a reasonable explanation of how this can be the case if poly-unsaturated fats are as healthy as they are claimed to be.

> Saturated fat consumption is decreasing, while unsaturated fat consumption is increasing

Do you have any source for this? The best I could find suggests that this is probably untrue: "An increase in saturated fat in 2008-12 is notable in several product categories, especially breakfast cereals and yogurt (approximately 15 percent) and frozen/refrigerated meals (6 percent)." [0]

I'd welcome any kind of nutritional study you can reference that shows the problems you're raising with PUFAs. Even if the above studies mentioned didn't control for hydrogenation, if PUFAs were bad for you, we would expect to see poor outcomes from those consuming them. It's weird that people in that category actually did best in the study.

> what is the one common feature of almost all food generally considered harmful?

It's far simpler than looking at added sugar content or amount/type of fat -- the commonality is simply, how processed is this. Any whole food you can consider healthy, but most harmful food is processed (and most processed food is harmful!)

[0] https://www.ers.usda.gov/webdocs/publications/85761/eib-183....

But Canola oil is higher in monounsaturated fats like Olive Oil: https://medlineplus.gov/ency/patientinstructions/000785.htm

Why is Canola oil bad if it has the same quantity of monounsaturated fats as Olive Oil?

Because it has substantially more poly-unsaturated fats. See this graphic for info: https://cdn.mos.cms.futurecdn.net/4DmwKT6rrQf2BMJQwvX2cX-650...

It's not really that saturated or mono-unsaturated fats are good for you, but that poly-unsaturated fats are bad for you. I realize this is contrary to what much of modern nutrition says, but the lipid science says the poly-unsaturated fats are worse because they react more with other molecules in your body.

Also, saturated fat consumption has been declining and unsaturated fat consumption increasing over the past decades while health keeps getting worse. To me, this suggests that something is wrong with our current nutritional understanding, and I believe the lipid science shows that the problem is the poly-unsaturated fats (as one part of it at least, it's obviously not monocausal).

*refined sugar, not all sugar.

sugar in a whole fruit aren't bad, the fibers in the fruit help your body break down and absorb the sugar over a longer period of time.

just don't eat refined food.

Sugar is sugar. If you are subject to metabolic syndrome it's really bad for you, even from fruit, if eaten in large amounts.

Any kind of concentrated sugar product is going to be unhealthy regardless of the process that got it there. Fresh squeezed orange juice and honey aren't refined, but they're still much too sweet to be consuming large quantities of.

If your concern is obesity and diabetes I encourage you to look up fruititarians. They consume 3000+ calories a day of fruit and loose dangerous amounts of weight. It's not healthy to consume such low fat and protein but it goes to show you can't gain weight on fruit juice.

Conjecture: it's sugar and polyunsaturated fats at the same time that cause issues.

The real concern is systemic inflamation caused by sugar (both high average levels and large spikes are bad)

You mean high blood sugar as in hyperglycaemia?

squeezing juice out of an orange is a level of refinement. You are reducing a whole food to separate components, much like pulling iron out of ore. It's weird to think of it as a refined food but it is to a degree.

I wouldn't classify it as a processed food, but maybe that's where people conflate the terms.

I've read that Safflower oil or Avocado oil are one of the healthiest oils to cook. Safflower oil is supposedly even good for you. As with everything, moderation is a key factor.

"Everything in moderation" isn't actually great diet advice. There's a paper floating around somewhere showing that people with a limited diet of healthy things fare better than people with a very wide diet that included unhealthy things.

My take is that "everything in moderation" is a mental crutch that people adopt when there's some part of their diet that they know isn't _good_ but that they don't want to give up completely. It is true that we can sneak in unhealthy food here and there without hugely detrimental effects, but that doesn't mean it's a good baseline practice.

The one scenario where it might be useful advice is with somebody whose diet is terrible, and you want to ease them towards a somewhat nutritionally positive diet; even in this circumstance, a more direct approach of "eat less crap and more good stuff" would be more accurate.

Most people aren't going to stick to healthy foods only though, thus moderation is "good enough", It's better to be at 75-80% and not feel guilty rather than 10% good food and 90% junk food because you just couldn't do the 100% good all the time diet

Think that comes down to the different smoke points of various oils. https://en.wikipedia.org/wiki/Template:Smoke_point_of_cookin...

You generally want to avoid smoke, so safflower oil and avocado oil are the best choices choices. But probably even better to not cook in oil at all, and just add olive oil (or your favorite source of fat) at the end

You are wrong, there's nothing indicating that PUFAs are as problematic as sugar or even problematic at all, on the contrary the evidence we have show they are beneficial.

It concerns me that your comment is the top voted, as it can lead to dangerous dietary extremism, say avoiding all PUFAs which are among other things implicated in helping the immune system "Paracrine interactions between adipose and lymphoid tissues are enhanced by diets rich in n-6 fatty acids and attentuated by fish oils. The latter improve immune function and body conformation in animals and people. The partitioning of adipose tissue in many depots, some specialised for local, paracrine interactions with other tissues, is a fundamental feature of mammals."https://pubmed.ncbi.nlm.nih.gov/15946832/

1. You shouldn't just throw in links to "support" your claims - to me this shows you don't understand what you're talking about, you should cite the relevant text otherwise it's just hand waiving.

The studies you cite are about radicals generated from PUFAs that are naturally a part of cell membranes, not from diet, and even goes against your claim by saying that PUFAs from diet help generate antioxidants that eliminate such radicals.

"Any change in the cell membrane structure activates lipoxygenases (LOX). LOX transform polyunsaturated fatty acids (PUFAs) to lipidhydroperoxide molecules (LOOHs)." i.e. cell membranes naturally have PUFAs."..."In order to remove LOO* radicals, plants and algae transform PUFAs to furan fatty acids, which are incorporated after consumption of vegetables into mammalian tissues where they act as excellent scavengers of LOO* and LO* radicals." - hey eating PUFAs help cells make radical scavengers. https://pubmed.ncbi.nlm.nih.gov/17914157/

2. Omega-3 is a polyunsaturated fats - yes they are less stable than SFAs, but that probably does not matter at all unless you're eating rancid oils. Polyunsaturated fats are not "extremely" reactive either whatever you mean by that.

Then we know that diets rich in PUFAs and MUFAs have positive effect on cholesterol ratios "We conclude that a mixed diet rich in monounsaturated fat was as effective as a diet rich in (n-6)polyunsaturated fat in lowering LDL cholesterol. " https://pubmed.ncbi.nlm.nih.gov/2761578/

Is it the vegetable oil or the fact that processed foods come with vegetable oil? Sauteed vegetables with a drizzle of olive oil is a bit different than a TV dinner.

It's a great idea in in theory, in practice I'm highly skeptical it will do anything but give police a new way to extract fines (bribes) from shopkeepers.

Why anything containing psychoactive drug is actually legal to sell to kids? There's a lot of reports how bad is caffeine to underdeveloped brain. And look at any developing nation: everyone is hooked to Coca-Cola.

> There's a lot of reports how bad is caffeine to underdeveloped brain.

Not going to do well on this site if you make baseless nonsensical claims like that.

Paper[1] from 2009 stating that: 1. We actually use caffeine as a first-line treatment in premature infants for treating apnea and 2. Nobody has done the research on adolescents to assess any negative impact on brain development.

[1] https://sci-hub.tw/10.1016/j.neubiorev.2009.01.001

> And look at any developing nation: everyone is hooked to Coca-Cola.

Everyone (more or less) is outside a few liberal, urban, health-focused pockets of the US, too. Or to sweet tea, or some other sugary caffeine drink. Unless you intended "developing nation" to cover those parts of the US, as well :-)

[EDIT] Not sure what rubbed people the wrong way about this, but if it's the qualifiers then it's my understanding that both "liberal" and "urban" are, independently or together, correlated with smaller waistlines and healthier lifestyles, in the US. Almost certainly including consumption of sugary drinks (indeed, this seems to peak in the "deep red" South, in the US, from what I can find). If that's wrong I'd be interested to know about it.

I don't know what the reports are about, but I don't think there is evidence that caffeine has negative impact on adolescent brains, most of the issues seem to be caffeine pills or caffeine drinks mixed with alcohol.

the problem is the lack of understanding of CICO in the CULTUREof the country.

Any other explanation is hiding the truth for some half-reasoning which mich the real point

Maybe so, although CICO (calories in, calories out) is a little oversimplified. In reality not all calories are equally satiating, nor are all calories equally digestible.

Additionally, measuring calories in food is done in a purely chemical fashion - the food is burned and the amount of heat energy released is measured. This of course does not actually measure how much energy your body is actually able to absorb (for example, dietary fiber burns just as well as refined sugar, but isnt absorbed the same in the body).

If you want a upper limit it's around 20000 calories. That's what eat people who go to the artic / antartic.

Honestly i think its WAY LESS oversimplified that people say it is. True you never know what you really ate, but if you note your average calories for a month, and then do +20% or -20% calories with the same type of food and same lifestyle you will get the exact weight loss / gain predicted from regressing on the first month.

After 40 everything once was good/tasty needs to be reduced a lot and or cut out of our diets. Our U.S. arteries are clogged no matter if your obese or not.