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Comment by m45t3r | Hacker News Reader

I have high blood pressure, and this is a step at the right direction. Current home devices to measure blood pressure are not really convenient, so I tend to only measure my blood pressure at home.

However, this is not what I want. I want a device that measure my blood pressure continuously (not necessarily all the time, let's say each 15 minutes). Why? Because I want to know how my behavior impacts my blood pressure. For example, does eating salty foods really increases my blood pressure, and for how much time.

Anyway, I still want this device since it seems so much better than what is currently available.

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That last thing about the effect of salt is something that has been bugging me for a bit. My understanding (at this stage, due to my lack of knowledge, it's more of an opinion, really) of this is that salt consumption slightly and temporarily raise blood pressure, but in no common measure to what an actual high tension is. But I have no real way to experiment with it.

> The relationship between salt and blood pressure (and the role of sugar) [5:45]

https://peterattiamd.com/rickjohnson/

#87 – Rick Johnson, M.D.: Fructose—The common link in high blood pressure, insulin resistance, T2D, & obesity?

Just listened to this podcast the other day from a preeminent researcher who studies this. Had some new to me information. Have a listen!

Was just about to post this. I listened to this yesterday, and it squares with what GP said about alcohol raising his BP.

Some people have sodium-sensitive hypertension. They eat excessive levels of salt and there is a measurable increase in blood pressure.

For most people, the body's normal processes handle the extra salt quite well, it's simply excreted. Blood pressure impact is minimal.

Where it can have a big impact is in people whose normal sodium handling processes are dysfunctional. A good example is congestive heart failure - poor cardiac output leads the body to increase blood pressure (by retaining more fluid) to compensate. Sodium intake can have a big impact in these folks.

You put it really well. All the concerns about the accuracy mentioned in other comments are valid but what is interesting to me is now having the ability to continuously monitor my BP (I have hypertension) and study affect of Work stress, exercise, diet and medicine.

I will be really curious to see the accuracy difference b/w these watch based measurements and the traditional one at my Doc. As long as they have a consistent error it is actually ok even if the readings are off a bit. Having a trend of measurements is more useful.

AS someone whith high blood-pressure and geek I used the Withings BPM Core in the last 4 months and found that salt actually increases my blood pressure, but for me nothing increases blood pressure more than alcohol. Eliminating alcohol was more efficient than eliminating salt. I 've heard about the sodium-potassium relationship but couldn't find a pattern

You should not expect to see an immediate change to your blood pressure after eating salty food, but you should expect a long-term change.

I'm reposting this from an older comment by myself (the links to pubmed should work but it's currently down):

>> Btw, since I'm idly browsing ncbi org, the following is a 2013 Cochrane meta-analysis of thirty-four randomised trials with 3230 participants.

>> 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.

Note again this is a Cochrane meta-analysis of RCTs, from 2013 (so quite recent). It's typical of reviews and meta-analyses since a long time and until now. There are a number of studies that have also reported not finding evidence of a link between salt consumption and blood pressure but it's important to remember that absence of evidence is not evidence of absence, especially in the light of _presence_ of evidence (from other studies). I.e. if n studies find "no evidence" and m studies find "evidence" of an effect then we have "evidence" of the effect, not "no evidence" of the effect. How we evaluate the evidence we have is another matter.

Also, note that it doesn't really matter how high your blood pressure goes when you're exercising or anyway being active. It's supposed to rise with activity.

What matters is what your blood pressure is at rest. I think of it as a baseline of sorts. If your blood pressure is elevated at rest, then you have hypertension. If it's elevated when you're running, then you have physical activity.

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