💧 Water guide

Alkaline Water vs RO Water: What the Evidence Actually Says

6 min readPublished 2 April 2026Updated 1 August 2026

What an alkaline purifier actually does

It is a standard RO purifier with one additional post-treatment cartridge. Water is purified by the RO membrane, sterilised by UV, and then passed through an alkaline or mineral cartridge that raises its pH, typically into the 8.5-9.5 range. Some premium systems use electrolysis instead of mineral dosing.

The important structural point: the alkaline stage sits after purification and adds no protection. It changes taste and pH, nothing more. Anyone selling an alkaline purifier as safer than a standard RO is misrepresenting how it works.

The health claims, assessed

'Alkalises your body' — not how physiology works. Blood pH is regulated within a very narrow range by your lungs and kidneys regardless of what you drink.
'Neutralises stomach acid' — your stomach is strongly acidic by design, and it is meant to be. Any alkaline water you drink is rapidly neutralised there.
'Cures acidity / reflux' — there is limited research on high-pH water and pepsin activity, but it is not an established treatment and does not address the cause. Persistent reflux warrants a doctor, not an appliance.
'Better hydration' — no credible evidence that pH affects hydration.
'Prevents disease / slows ageing' — no credible clinical support.
What is true: some people find higher-pH water smoother and less sharp, and drink more of it as a result. That is a real benefit, just a modest one.

Important

Be sceptical of any purifier marketed with therapeutic claims. In India, therapeutic claims about drinking water attract regulatory scrutiny, and a brand willing to overstate health benefits is a brand whose other specifications deserve checking too.

Is the premium worth it?

So the honest recommendation: if you have tasted alkaline water and prefer it, and the extra ₹5,000-8,000 plus an annual cartridge is comfortable, buy it — the KENT Supreme Alkaline and Havells Max Alkaline are both well engineered. If you are considering it because of health claims you read online, save the money and buy a better standard RO instead.

	Standard RO+UV	Alkaline RO
Typical price	₹16,000 - ₹20,000	₹20,000 - ₹30,000
Purification capability	Same	Same
Output pH	~6.5 - 7.5	~8.5 - 9.5
Extra annual consumable	No	Yes, alkaline cartridge
Proven health benefit	Safe water	None beyond safe water
Taste	Clean	Smoother, preferred by some

Frequently asked questions

Is alkaline water better than RO water?

For safety, no — they are equally safe, since the alkaline cartridge sits after the RO membrane and adds no protection. For taste, many people prefer alkaline water's smoother mouthfeel. For health, mainstream clinical evidence does not support the benefits claimed for alkaline water in healthy adults. Buy it as a taste preference, not as a health intervention.

What is the ideal pH for drinking water?

BIS IS 10500 accepts a pH range of 6.5 to 8.5 for drinking water. Alkaline purifiers typically output 8.5 to 9.5, slightly above that band but not harmful for normal consumption. If you have a kidney condition or take medication whose absorption depends on gastric pH, ask your doctor before switching.

Does alkaline water help with acidity?

Some people report symptomatic relief and there is limited research on high-pH water and pepsin, but it is not an established treatment and it does not address the underlying cause of reflux. If you have persistent acidity, see a doctor rather than buying an appliance.