On our packaging, we have a warning saying REVIVE is not appropriate for people with hypertension. Regulations require that we do so. However, this space allows us to give a more comprehensive and considered response to a topic that cannot be dealt with in a sentence.

Stage 1 hypertension is blood pressure more than 130/80 mm Hg. Some people have elevated blood pressure (higher than normal) that is not yet in the category of hypertension. This FAQ applies to both elevated blood pressure and hypertension. The higher your blood pressure, the more conservative you should be, as a matter of common sense.

Most (but not all) of the medical establishment holds the view that sodium increases blood pressure and low salt diets have been a cornerstone of conventional medical advice for decades. REVIVE has a relatively high level of sodium. So, the idea that someone would take REVIVE with higher blood pressure, is anathema to most in the healthcare profession.

Yet, like many other things long regarded as bad for you - for example saturated fat, eggs and butter - the world is changing. New, contrary evidence is emerging, leading voices in the scientific community are speaking out with a different message and many members of the public are taking their health into their own hands and getting great results with a contrarian approach.

It turns out that conventional guidelines have often been wrong, and have sometimes been harmful. We think that salt falls into this category. The simple idea that "salt is bad" is not universally correct and is definitely more nuanced than originally thought.

Many respected, thoughtful doctors and scientists are now advising that salt is not bad, and, in fact, that low salt is harmful and can raise blood pressure. This makes things thoroughly confusing.

We are not here to give medical advice. We are not allowed to do so, and nothing in this FAQ should be construed as such, but here is our interpretation, made as simple as we can. It is taken from sources like Dr Richard Johnson (Nature Wants Us To Be Fat), one of the world's blood pressure experts, and many others:

1. 75% of people are NOT salt sensitive, meaning that higher sodium does not increase their blood pressure.

2. Sodium taken as part of hydration, in other words, with the right amount of water is more benign (and therefore safer) than sodium taken with food. This fact isn't widely known or understood.

3. During exercise, you lose sodium and other minerals (like potassium and magnesium) that need to be replaced, along with water. This is true, irrespective of your blood pressure.

4. People eating a low carb diet, practicing intermittent fasting and exercising regularly need more electrolytes, particularly sodium. This also includes people with higher blood pressure.

So, here are some tips for using REVIVE safely and cautiously if you choose to do so with higher blood pressure:

1. Use REVIVE when exercising, not as an everyday drink, until you are sure there is no adverse effect on your blood pressure.

2. Dilute REVIVE in more water - we suggest one sachet per 1L, instead of 750ml.

3. Split 1 REVIVE sachet into 2 x 500ml portions - drink only 1 portion per day.

4. Sip slowly.

5. Monitor your blood pressure on days you take REVIVE and on days you don't, so you can compare.

6. Monitor how you feel.

7. Regulate your overall sodium intake, in other words your entire dietary intake of salt. On days you take REVIVE, you may wish to be more cautious with your other salt intake.

As a last point, there is evidence pointing to 5g of sodium per day (which is 13.8g of salt) as being the optimum level, even for people with known cardiovascular risk (which includes people with higher blood pressure). Most people aren't getting near this level, even with REVIVE, which has 1g of sodium per sachet.

We hope this answer provides some context for you to make your own judgment and to use REVIVE safely if you choose to do so.