Blood pressure and salt

Does a high salt intake affect blood pressure?

Can high blood pressure be lowered by avoiding salt?

There is indeed a connection between the amount of salt in the body and blood pressure. The body needs certain salt levels, which include the table salt we use. The more salt there is in the body, the more fluid is needed to balance it. Fluid balance is controlled by the kidneys. If you drink too little while eating a lot of salt, cells lose the water they need. When theres not enough water in the cells, you get thirsty. Because of the increase in volume, a higher fluid content always leads to higher blood pressure.

Experiments have shown that healthy people can lower their blood pressure by eating a low-salt diet and vice versa. Whether long-term excessive salt intake harms healthy people is, however, completely unclear. Many studies on this topic are poorly designed, so clear statements are lacking. Scientifically rigorous double-blind trials that study the long-term effects of excessive salt intake in humans are not feasible, because they would be ethically highly questionable. Imagine intentionally getting a group of healthy volunteers to eat a high-salt diet to see whether they later become ill or die earlier unthinkable!

What is clear is that in at least one third of the population, high salt intake affects blood pressure. Among people with high blood pressure, the proportion of salt-sensitive individuals is even around half meaning a lower-salt diet lowers blood pressure in about one third of the general population and in about half of people with hypertension. Being overweight, having diabetes, kidney disease or high stress levels often makes the negative effects of too much dietary salt more likely.

In November 2023 the results of an American study were published that compared participants blood pressure during one week of low-sodium eating with one week of high sodium intake. The study included people aged 50 to 75 who had normal blood pressure, well-controlled hypertension, or uncontrolled/untreated hypertension. All of them, however, already consumed too much sodium with their usual diet. During the high-sodium week the participants received an extra 2,200 mg of sodium per day to add to their normal meals. In the low-sodium week the diet contained only 500 mg of sodium and, as an alternative, was salted with 4,500 mg of potassium.
In about 75% of participants, blood pressure in the low-sodium week was on average 8 mmHg lower systolic and 3 mmHg lower diastolic than in the high-sodium week. So, regardless of whether they had high blood pressure or not, the majority of participants showed a drop in blood pressure and that after only one week!

The problem with todays diet is the many hidden salts we consume in industrially processed foods without noticing. Ready meals in particular usually contain much more salt than people expect. In a press release from Feb 20, 2012, the Federal Institute for Risk Assessment (BfR) addressed the topic of high blood pressure and salt. It recommended reducing the salt content of ready meals in Germany. This appeal was, of course, aimed at manufacturers of processed foods, not consumers. The BfR named bread, dairy products (for example cheese) and meat and sausage products as particularly problematic. There are other product groups such as snacks and sauces that also contain too much salt, but these are not eaten as frequently as the products mentioned first.

This view was supported by Stiftung Warentest, which examined 74 products in the April 2012 issue of its test magazine. The 5 grams of salt per day recommended by the German Nutrition Society (DGE) are reached quickly and often exceeded.

How relevant the salt content of industrially produced foods is is shown by a modelling study from the UK published in 2026. The researchers calculated what would happen if manufacturers fully met the UKs salt-reduction targets for sausages, cheese, bread, ready meals and out-of-home products. The result: average salt intake would fall from about 6.1 to 4.9 grams per day.

Over a 20-year period this could prevent about 103,000 cases of ischemic heart disease and 25,000 strokes. Although the study is based on models and refers to the UK, it highlights a basic problem very well: a large part of the salt we consume every day doesnt come from the salt shaker but from everyday foods we eat regularly.
For people with high blood pressure this means: its not just table salt that matters, but especially cheese, cold cuts, bread, ready meals and take-away food. Choosing lower-salt options in these categories often reduces salt intake more effectively than simply salting food less at the table.

Salt calculator for mineral water:

Sodium: mg/L Chloride: mg/L

Salt: 1.7 mg/L

Salt levels to know:

Product	Salt content
Roll (to bake at home)	approx. 1.1 g
Slice of toast bread	approx. 0.4 g
100 g cereal	approx. 0.7 g
100 g raw ham	approx. 8.0 g
100 g cooked ham	approx. 2.3 g
Bratwurst	approx. 2.0 g
Vienna sausage	approx. 1.0 g
Potato dumpling (ready-made)	approx. 1.2 g
100 g ready-made potato salad	approx. 1.0 g

These are only rough guidelines. Foods always show natural variations.

Caution with effervescent tablets

Researchers at the Saarland University Hospital found that dietary supplements taken as effervescent tablets contain a lot of sodium. This applies to both over-the-counter and pharmacy-only products. The effervescent supplements examined contained on average 283.9 mg of sodium. The top contender was a vitamin C effervescent tablet with 564.7 mg of sodium, which corresponds to 28% of the recommended daily maximum sodium intake. Remember: thats in a single effervescent tablet.

Findings about the dangers of a low-salt diet

In 2012 a meta-analysis of studies with a total of over 2,700 participants found that a low-salt diet in heart patients drastically increased overall mortality and the risk of death from heart failure. Stress hormones rise. On a low-salt diet there can be a minimal reduction in blood pressure. Blood pressure values fell by about 1.27 mmHg systolic and about 0.05 mmHg diastolic. However, this is contrasted by a dangerous increase in some metabolic markers. For example, increases in the stress hormones renin, aldosterone, adrenaline and noradrenaline were found. More on this in the article about the link between stress and high blood pressure. Because older people have a lower proportion of body water, a low-salt diet also brings a faster risk of dehydration. Experts today consider such risks to outweigh the benefit of the minimal blood pressure reduction achieved by cutting salt intake.

Newer studies from 2015, 2016 and 2020 reached no different conclusions and confirmed that a salt-rich diet can promote high blood pressure.

Conclusion

Experts currently disagree on how strongly salt harms the body. Both very low and very high salt intakes are seen as critical. People with high blood pressure are advised to consume no more than 5 grams of salt per day, because and experts agree on this a high salt intake has a negative effect on high blood pressure.

Interesting to know:

A Chinese study has found that spicy food can help reduce salt intake. The compound capsaicin in peppers and chilis, which gives the heat, makes dishes taste saltier as a side effect. This means less salt is needed, which can in turn affect blood pressure.

October 2020:

In a rat study, researchers found hints of an active substance that could help with salt-sensitive high blood pressure. It is known that some difficult-to-control high blood pressure is caused by too much salt intake. As described above, not everyone reacts the same way to salt, and there are salt-sensitive hypertensive patients. For this group, scientists may have found a drug treatment option with an alpha1-adrenoceptor blocker if the effect is confirmed in clinical trials.

August 2025:

A study provided evidence that high salt intake may also affect the brain and thus possibly raise blood pressure. In experiments with rats that received water with 2% table salt daily, researchers observed that certain immune cells in the animals brains were activated and triggered inflammatory reactions. At the same time, more of the hormone vasopressin was released, which also raises blood pressure. The researchers see this as another possible target for treating especially therapy-resistant high blood pressure.

Women more salt-sensitive

A review article published in August 2022 reports on the occurrence of salt-sensitive blood pressure in different sexes. The researchers found that women react more salt-sensitively than men at any age. Especially after menopause, salt-sensitive blood pressure occurs more often in women and to a greater degree. It is suspected that this is an effect of hormonal changes during menopause. Hormones that likely protected women before are present in lower amounts after menopause.

Salt substitutes, salt alternatives

Salt substitutes are seasoning products often sold as "blood pressure salt" or "diet salt." Unlike regular sea or rock salt, they are not made entirely of sodium chloride but partially of potassium chloride. This reduces the blood-pressure-increasing effect of sodium chloride. This has been studied and demonstrated in various studies. A January 2024 article in Hypertension deals with salt substitutes and suggests recommending a salt alternative composed of 75% sodium chloride and 25% potassium chloride for people with high blood pressure, provided this is not contraindicated by other illnesses or an existing potassium medication. These salt substitute products are not suitable for people with known kidney disease, because they can cause hyperkalemia that is, high potassium levels in the blood. Hyperkalemia can also be caused by excessive potassium intake and is considered dangerous because it disrupts the electrolyte balance. Possible symptoms can include diarrhea, nausea, muscle twitching up to potentially dangerous heart rhythm disturbances.

Sources:

This article comes from BloodPressureDB – the leading app since 2011 that helps hundreds of thousands of people monitor their blood pressure every day. Our content is based on carefully researched, evidence-based information and is continuously updated (as of 04/2026).

Author Sabine Croci is a certified medical assistant with many years of experience in internal medicine and cardiology practices as well as in outpatient care. Since 2015 she has led the editorial team at BloodPressureDB. With additional qualifications as a paramedic, first responder, and training in various therapy and emergency areas, she provides well-founded, practical, and reliably reviewed information.