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It isn’t clear at all how refining oil makes it materially “worse” in terms of health than the unrefined equivalent. That claim lacks both evidence and a mechanism of action.

Every argument I’ve seen demonstrates a pretty fundamental misunderstanding of the chemistry. These same bad chemistry takes are repeated everywhere by influencers. This isn’t unique to the oil discussions, dietary health is rife with vibe-based chemistry takes that are obviously unscientific.

Among other mechanisms, refining removes nutrients and other beneficial molecules, while purifying taste and reducing volume making it easier to overeat.

But the worst part isn't refining the oil itself, but the use of these oils in ultra-processed foods along with refined sweeteners, colorings, and fillers. Even if refined seed oils themselves aren't harmful, avoiding them is likely to be beneficial because it leads to avoiding ultra-processed foods.

Colorings and fillers are not that bad for you. You, and other, are missing the forest for the trees here: diets high in fat, sugar, and calories lead to heart disease and metabolic syndrome.

Replacing "seed oils" with hamburgers and french fries fried in tallow won't magically help your health. If anything, you would die quicker from the huge amount of saturated fat you're now intaking.

Ultra processed foods are bad generally, yes, but not because they're processed, but because they're high in fat and sugar, while being calorically dense with no nutritional value.

> Replacing "seed oils" with hamburgers and french fries fried in tallow won't magically help your health. If anything, you would die quicker from the huge amount of saturated fat you're now intaking.

I'd like to see your evidence for the first claim.

The second claim is not as well supported as you might think. A recent Cochrane review published by The American Academy of Family Physicians (AAFP) rated "Reduction in Saturated Fat Intake for Cardiovascular Disease" as having Unclear Benefits with no significant effect on all-cause or cardiovascular mortality. This is based on randomized controlled trials that measured endpoints directly rather than LDL levels.

https://www.aafp.org/afp/2022/0100/od2#afp20220100p19a-b3

No, we know that eating less saturated fat and replacing it with unsaturated fat, such as those found in seed oils, can reduce your risk of CVD as much as statins.

https://www.heart.org/en/news/2019/10/21/advisory-replacing-...

We know, for sure, that eating less saturated fat reduces your markers that put you at risk of cardiovascular disease. Your study points that out. The problem with assessing cardiovascular mortality is that takes many many years to come home to roost. As your source points out, most studies were only 12-24 months.

I've seen emerging evidence that saturated fat and LDL is not even causative, and that it's perhaps triglycerides that are instead relevant
As evidence for mortality related to saturated fat, that AHA statement cites only three sources.

First, in the Oslo Diet-Heart Study, "there were fewer cardiovascular deaths in the experimental group by 27% (P=0.09)", a non-significant result.

Second, it cites the reduction in CHD deaths in Finland between 1972 and 1992, attributing 50% of the reduction to cholesterol levels. But similar reductions occurred in many nations at that time, largely due to reduced smoking, improved treatment, and other changes that should not be ignored. There is no clear link to saturated fat here.

Third, it cites the Nurses’ Health Study and Health Professionals Follow-up Study, an observational study that didn't isolate PUFA intake, and is likely to be confounded by diet quality.

I would describe that evidence as weak-to-moderate at best.

The evidence regarding LDL is stronger, but that's a concern that should be measured and treated individually. People do not respond identically to diet, not everyone has high LDL, and there are many ways to lower it if needed. Personally, I don't worry much about saturated fat because my LDL is under 70.

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>Among other mechanisms, refining removes nutrients and other beneficial molecules, while purifying taste and reducing volume making it easier to overeat.

Should we cancel vaccines and water purification while we're at it? It's not hard to come up with vaguely plausible reasons for why those are bad as well, eg. "hygiene hypothesis", "gut microbiome", or whatever.

>But the worst part isn't refining the oil itself, but the use of these oils in ultra-processed foods along with refined sweeteners, colorings, and fillers. Even if refined seed oils themselves aren't harmful, avoiding them is likely to be beneficial because it leads to avoiding ultra-processed foods.

It's ironic you cite ultra-processed foods, another category which has questionable rigor and applicability, but people nonetheless defend because "Even if ultra processed foods themselves aren't harmful, avoiding them is likely to be beneficial because it leads to avoiding unhealthy foods."

> It's ironic you cite ultra-processed foods, another category which has questionable rigor and applicability, but people nonetheless defend because "Even if ultra processed foods themselves aren't harmful, avoiding them is likely to be beneficial because it leads to avoiding unhealthy foods."

The evidence that ultra processed foods are harmful is quite strong, much stronger than the association with saturated fat intake. Are you really suggesting that they might not be unhealthy?

The objection isn't over whether "ultra-processed foods" as a group tend to be unhealthy, it's that the classification is not rigorous, and conflates what's actually unhealthy or not with an heuristic that's at times inaccurate.

>Everyone knows that greens are good for your health and red meat is not. But everyone would laugh if I were to propose that red foods are dangerous and green ones healthy. I could prove my thesis making use of a few additional rules, such as postulating that some shades of red, tomatoes and apples for instance, should not be counted as red.

>The Nova classification system, which sorts foods into four categories depending on the degree of processing they undergo, uses similar logic. There is no scientific justification for the assumption that the number of processing steps is of any relevance for the health properties of foods. Making “ultra-processed” popcorn or chips is exceedingly simple. Making “minimally processed” natural yogurt requires some 20 processes.

>Heating is the process that affects foods the most, but heating is afforded no attention in Nova. It does not neatly fit into the processed or unprocessed scheme. In some cases it is essential for public health, in others it may induce carcinogens. And in a blatant example of the arbitrariness of the Nova classification, putting a loaf of bread into a bag moves it from the minimally processed to the ultra-processed category.

>The flawed, but intuitively easy to grasp, label of ultra-processed food is a handy justification for blaming food-related health problems on profit-hungry food companies. And it enables politicians to divert funding from serious research to meaningless eye-catching interventions.

>Petr Dejmek

>Emeritus professor of food engineering

>Lund University

>Lund, Sweden

The Nova classification system isn't based on the number of processing steps, it's based on ingredients.

Putting a loaf of bread into a bag certainly doesn't move it from the minimally processed to the ultra-processed category. That false claim is based on the fact that most bread sold in bags is ultra-processed, but it's not the bag that makes it so.

I think that professor of food engineering may have a conflict of interest related to the foods he creates for a living.

>The Nova classification system isn't based on the number of processing steps, it's based on ingredients.

So going back to the quote, is the potato chips vs yogurt example accurate?

>That false claim is based on the fact that most bread sold in bags is ultra-processed, but it's not the bag that makes it so.

What makes them ultra-processed then? Even the home made loaf is made from wheat that's dehusked, ground to a powder, and then chemically treated (bleaching). Making it into a dough and then baking it involves even more processing. The final product resembles the inputs almost as little as instant mash potatoes resembles potatoes. The only real difference is the use of dough conditioners and industrial sized ovens, but given all the previous steps, it seems arbitrary to draw the line of "ultra-processed" there.