Soft Water - Is It Safe to Drink?

As the UK’s leading commercial water treatment specialists and providers of water softeners, we get asked a lot of questions about water. But none are asked so often as whether soft water is safe to drink. 

Some companies will make this out to be a black and white topic – they will say that it is, or that it isn’t. This is understandable because it is far easier to simply take a stance (usually to say that it is not safe). This is because the actual, potentially more frustrating answer is – “it depends”.

For the record, we err on the side of recommending you don’t drink softened water. But we want to break down our reasoning in the section below. 

As per the NHS website, it is recommended that the maximum daily intake of sodium for adults is no more than 2.4g of sodium. That’s around one tea spoon of salt. This is reduced to 2g for a low sodium diet and 0.8g for infants who are beginning to eat.

And how much sodium is in water? Well, that depends on where you live. In Devon I’ve found sodium levels are as low as 9mg/l, whilst in Haverhill, Suffolk, they’re nearly 30mg/l.

For those shrewd mathematicians amongst you, you will have determined that you’d have to drink  80 litres of hard water in Suffolk to hit your limit, and 240 litres in Devon. Frankly, you would drown before sodium became an issue.

But what about softened water? How much sodium does the softening process add to your drinking water?

Let’s return to Haverhill. There they have a total hardness of 490.5 mg/l. For every 100 mg of hardness it encounters and washes away, your softener will add 46mg of sodium. This means in Haverhill, one of the hardest water areas in the country, 225mg/l of sodium is being added to the water. On top of the 30mg already in the water, this takes the total to 255mg/l of sodium – this is 55mg/l over the acceptable national standards (200mg/l).

Given that adults are recommended to drink 3.2 litres a day, this would still leave you just over 1.5g of sodium a day as part of your diet. So why do we recommend you keep your drinking water tap hard?

The British Heart Foundation says that the average Brit eats 8.4g of salt a day. That’s 3.36g of sodium. That’s 40 per cent more than the national guideline. And the UK’s national target is 15 per cent higher than the World Health Organisation’s target of 5g of salt a day. 

In short – drinking soft water could increase your sodium intake through drinking water by up to 2,450 per cent. 

Many water softener providers say that the concerns surrounding sodium in soft water is a myth. Why wouldn’t they? They don’t want you to be scared of their product. But ultimately, the results of a water softener in a hard water area could cause your drinking water to go against UK guidelines and impact your health. 

But just because water softeners add sodium to your water doesn’t mean you need to be scared of them. Here at Genus we believe best practice is to keep your main drinking water tap hard, whilst applying soft water to every other area of your house. Alternatively, a reverse osmosis system could be installed to strip away the sodium and any other unwanted chemicals and pesticides.

If you have concerns about sodium or anything else in your water, get in touch today. We pride ourselves on tailoring your water to your needs.