How Crisco Made Americans Believers in Industrial Food

https://www.ncbi.nlm.nih.gov/pubmed/3510595

Sodium and hypertension. A review.

Arch Intern Med. 1986 Jan;146(1):179-85.

Abstract

Abnormal sodium metabolism may be critical in the causation of certain forms of hypertension, particularly salt-sensitive hypertension. Long-term restriction of sodium intake in patients at high risk for the development of hypertension may reduce the chances of established hypertension occurring later. These high-risk patients in whom subsequent hypertension may be prevented include normotensive patients with family histories of hypertension, elderly patients, black patients, and those with low-renin hypertension. Treatment of hypertension with moderate sodium restriction to 70 mEq/day will significantly reduce blood pressure in a large percentage of patients, particularly known salt-sensitive hypertensive patients. This degree of restriction is also an effective adjunctive therapy for patients receiving antihypertensive medications. There is convincing experimental, epidemiologic, and clinical evidence that moderate sodium restriction helps prevent and assists in the treatment of hypertension in those patients who are genetically predisposed to develop primary hypertension or who already have hypertension. There is no evidence that this degree of sodium restriction is harmful.

My hunch is that for every study we could find in the bibliography reporting that there is no correlation between high salt consumption and high blood pressure, we would find another 10 that say the opposite. Personally, I don't have the time, or the background, to figure out how to evaluate the quality of an epidemiological study. So I base my assumptions on the current expert opinion that continues to be that too much salt is bad for you especially if you have high blood pressure (or are at risk for it, like the review above says).

Edit: also, remember the basic rule that "absence of evidence is not evidence of absence". But _presence_ of evidence _is_ evidence of presence. If 10 studies find "no evidence" that lowering salt intake reduces hypertension risk and one study finds that it does, then we have "evidence that lowering salt intake reduces hypertension" and we do not have "no evidence that lowering salt intake reduces hypertension". How we interpet the evidence we do have is another matter, of course.

I'm quoting the conclusions section but as usual the abstract has multiple sections including a Results section that's a bit large to post (but interesting to read):

https://www.ncbi.nlm.nih.gov/pubmed/23558162

BMJ. 2013 Apr 3;346:f1325. doi: 10.1136/bmj.f1325.

Effect of longer term modest salt reduction on blood pressure: Cochrane systematic review and meta-analysis of randomised trials.

CONCLUSIONS:

A modest reduction in salt intake for four or more weeks causes significant and, from a population viewpoint, important falls in blood pressure in both hypertensive and normotensive individuals, irrespective of sex and ethnic group. Salt reduction is associated with a small physiological increase in plasma renin activity, aldosterone, and noradrenaline and no significant change in lipid concentrations. These results support a reduction in population salt intake, which will lower population blood pressure and thereby reduce cardiovascular disease. The observed significant association between the reduction in 24 hour urinary sodium and the fall in systolic blood pressure, indicates that larger reductions in salt intake will lead to larger falls in systolic blood pressure. The current recommendations to reduce salt intake from 9-12 to 5-6 g/day will have a major effect on blood pressure, but a further reduction to 3 g/day will have a greater effect and should become the long term target for population salt intake.

Remember that this is a meta-analysis and quite recent (6 years ago). I think my hunch above that we'd find many more studies supporting the mainstream view is not off.

Though even then, the features would have to be things people actually expect to get better value from. E.g. "snooze emails for later" vs "our server runs on golang"...though if your audience is super core golang fanboys then maybe the latter would be useful as well :)