How Crisco Made Americans Believers in Industrial Food

Olive oil quality can depend on many things: where it comes from, how it is made, who makes it, etc.

The one that's considered best is olive oil produced only from olives (i.e. no kernels) and only by mechanical means (specifically: no heat and no chemical treatments; so it's called "cold-extracted"). That's the quality that's sold as "extra virgin olive oil" though from what I understand there is no strict standard for what that means exactly.

Then there's provenance. Generally, Spanish olive oil is considered best with Greek second (unless you ask a Greek of course) and Italian a distant third. Other countries in the Med also make it, e.g. Morocco etc. Italian olive oil has often been found to be adulterated, substituted for lower quality olive oils or just to be a mix of non-Italian olive oils (primarily Greek, apparently) so it's a case of not knowing what you eat.

Anyway, I live in the UK where olive oil is imported and the good stuff tends to be expensive (£30ish for 25lt of Greek extra virgin but of course most people will buy smaller bottles that are more expensive). So my guess is that most olive oil consumed outside the Med tends to be of inferior quality, just because people don't know it well enough to justify spending the price.

So if you experiment with it- get the good stuff. To be honest, I just get the stuff I always do and I have never had to think about quality or smoke points, so my advice is probably a little vague.

Er. You won't set your house on fire just because some crazy Greek person on the internets said it's safe to cook with olive oil, eh? :)

That sounds very vague- what is "years ago" and what are "modern standards"? If "modern standards" are better for salt studies- are they also better for, e.g. drugs research, or physics or chemistry, etc?

I think probably not. What I understand the big difference is between now and the past (let's say the 1950's), in terms of scientific standards has more to do with ethical requirements, rather than methodology. More modern studies are also more likely to use more recent statistical tools, or to rely more on automated tools and software packages, but that doesn't meant the newer studies are more accurate.

I also don't know why you say that salt affects different people with high blood pressure differently. My understanding is that there is variability between _studies_, so some studies have found that hypertensives that reduce their salt intake see a reduction in their blood pressure, some have not, but that doesn't mean that hypertensives react to salt differently- it means that different studies had different results and that's all. And variability among studies' results is clearly expected, given the different methodologies etc.

Generally, I'd say it's hasty to discard data and results collected over many years because some -but not most- modern studies have different results. In such cases the prudent thing is to wait and see before making up your mind. Currently, the bulk of the data supports the mainstream view that salt consumption over some amount is associated with raised blood pressure. The wise thing to do is to take that into account and manage your consumption accordingly.

Another thing: how many people (say, under 30) know what their blood pressure is and how it's affected by salt? I know, because I have a relative with kidney disease and I often measure my blood pressure with them, and take notes. Most people though - they have no idea.

So again- don't be hasty. It's difficult to know how salt consumption affects the general population, but if anyone wants to know how it affects them, personally, they don't need to rely on studies, new or old. All they have to do is use a blood pressure monitor once or twice a day for a few weeks.

And I personally suggest everyone does, because what happened to my relative was downright scary. They had splitting headaches for a long time (years) and they only found out the reason when we visited a doctor for something unrelated. A nurse asked a question about general health and I replied that my relative has these splitting headaches (my relative would never bring up something so trivial themself!). It turned out those headaches were the result of 200/100 hypertensive episodes that were happening with regularity. Hypertension was likely either the root cause, or a contributing factor to the damage to my relative's kidneys (and also caused by that damage, in a real nasty feedback loop)- but we had no idea it was even there. And btw, my relative has definitely been able to control their blood pressure by cutting down drastically on their salt intake (they take drugs, of course, but salt still affects them very clearly).

Blood pressure is such a basic vital sign that's so easy to measure. It's so easy to know, studies or no studies, how salt affects you. And yet, most people never measure it and instead we end up having these arguments on the internets about what this study or that study says about salt, in the general population, in the abstract. I don't quite get it.

“Rigorous sodium deprivation can lower the blood pressure of some patients with essential hypertension (at best, 30% to 50% of patients). In the rest, sodium depletion is ineffective and, in some instances, can raise the blood pressure and cause adverse clinical effects. In normal persons, it is difficult to affect blood pressure even with drastic changes in salt intake; for the blood pressure to rise even slightly, it may be necessary to consume more than 800 meq/d. There is no evidence to indicate that a widely applied, moderate reduction of salt intake could prevent the development of hypertension. The evidence suggesting that such moderate salt intake would significantly lower blood pressure in the patients with sodium-sensitive essential hypertension is weak. Human hypertension comprises a heterogeneous spectrum of abnormal vasoconstriction-volume interactions. Sodium deprivation, like other forms of therapy, should be applied only to those patients in whom its effectiveness has been established.”

https://www.ncbi.nlm.nih.gov/pubmed/6847013

Just because people can't agree about where the grey areas are versus where the defined areas are does not mean that there are no areas worth defining or that we should avoid defining those areas for ourselves because other people disagree. It's sort of like driving speed. Some people believe that average faster speeds are safe, but people who drive faster than they drive are unsafe. Other people will think slower speeds are safe and anyone who drives faster than they drive are unsafe. This doesn't mean that there aren't "real" safe speeds or that the idea of a safe driving speed is meaningless. We can still get closer to real food or real safe driving speeds even if our targets vary.