Is TDS Less Than 50 Good for Drinking Water?

Did you know that water with TDS less than 50 ppm is often too pure to carry essential minerals? That’s right—while many think lower TDS is better, the truth is more complex. TDS (Total Dissolved Solids) is one of the most misunderstood aspects of water quality, especially for households using RO purifiers. In this blog, we explore whether water with TDS under 50 is truly good for your health, what global standards say, and how you can balance purity with mineral content.

1. Introduction to TDS in Drinking Water

TDS stands for Total Dissolved Solids and represents the total concentration of dissolved substances in water, including minerals, salts, and organic matter. Measured in parts per million (ppm), TDS is a key indicator of water quality.

Typical sources of TDS include:

• Calcium and magnesium (hardness)

• Sodium, potassium

• Bicarbonates, chlorides, sulfates

• Trace metals like iron and zinc

While high TDS levels can make water taste salty or metallic, excessively low TDS can also be problematic because it indicates a lack of essential minerals.

2. What Does a TDS Level Below 50 Indicate?

A TDS level below 50 ppm is considered very low and usually the result of intense filtration like reverse osmosis (RO) or distillation. Such water is extremely pure but almost devoid of minerals.

What causes TDS below 50?

• Advanced multi-stage RO systems

• Use of deionization filters

• Water from sources like rain or condensation (naturally low in dissolved solids)

While this seems ideal for laboratory use or battery water, it raises questions when it comes to drinking water.

3. Is TDS Less Than 50 Good for Health?

Here’s where the concern begins. Drinking water with TDS less than 50 might be too "empty." It may not have enough calcium, magnesium, or other minerals necessary for bodily functions.

Possible health effects of low TDS water:

• Mineral deficiency over time

• Altered taste — flat or bland

• Poor hydration as water with zero minerals lacks electrolytes

• Leaching effect — demineralized water may draw minerals from your body

A 2004 World Health Organization (WHO) study suggested that consuming demineralized water over the long term could negatively impact calcium and magnesium intake, especially where diet lacks these nutrients.

4. WHO and BIS Guidelines on TDS Levels

To understand what constitutes safe water, let’s look at two major standards:

✅ WHO Guidelines:

• Ideal TDS range: 100–300 ppm

• Water below 30 ppm may not be suitable for long-term consumption

✅ BIS (Bureau of Indian Standards) Standards:

• Acceptable limit: Up to 500 ppm

• Permissible limit (in absence of alternate source): Up to 2,000 ppm

Clearly, water with TDS less than 50 falls below the ideal range, especially when the goal is nutritional adequacy and taste.

5. How RO Systems Affect TDS Levels

Reverse Osmosis (RO) systems are highly effective in reducing contaminants—but they often remove up to 95–99% of dissolved solids.

Why is this an issue?

• Many RO systems do not include mineral cartridges by default

• They may reduce TDS too much, especially when incoming TDS is already low (e.g., <200 ppm)

• This can result in water with TDS less than 50 ppm

TDS level in RO water depends on:

• Input water quality

• RO membrane efficiency

• Pre-filters and post-filters

• Use of mineral boosters or TDS controllers

6. Potential Risks of Extremely Low TDS

Here are some scientifically backed concerns when TDS is too low:

7. Ideal TDS Range for Drinking Water

To keep things simple, here’s a breakdown of TDS ranges:

Thus, the ideal TDS for drinking water lies between 150–300 ppm, balancing both purity and mineral content.

"For a deeper understanding of what qualifies as safe TDS, check out our detailed guide on the minimum TDS for drinking water."

8. How to Test and Adjust TDS at Home

How to Test TDS:

• Use a digital TDS meter (costs ₹200–₹600)

• Dip the probe in a glass of water and read the number on the screen

• Test both raw and RO-treated water

How to Adjust TDS:

• Use TDS controller in RO system

• Install mineral cartridge or alkaline filter

• Mix RO water with a portion of filtered but unsoftened tap water (if safe)

Maintaining TDS between 150–300 ppm ensures you drink water that hydrates and nourishes.

9. Common Myths About Low TDS Water

❌ Myth 1: Lower TDS means better water

Not always. Below 50 ppm, water lacks essential minerals.

❌ Myth 2: All bottled waters are mineral-rich

Many bottled waters are purified via RO and may have TDS < 50, unless minerals are added later.

❌ Myth 3: RO water is unsafe

Not unsafe—but it needs proper mineralization to make it balanced and beneficial.

10. Conclusion: Should You Drink Water with TDS < 50?

While ultra-low TDS water is technically "pure," it's not ideal for drinking over long periods. Your body needs a certain amount of minerals—especially calcium, magnesium, and potassium—for hydration and biological functions.

Water with TDS less than 50:

• Is too soft to carry beneficial minerals

• Tastes flat

• May negatively impact mineral balance in the body

Instead, aim for TDS between 150–300 ppm using a RO system with a TDS controller or mineral cartridge.

11. FAQs About TDS in Drinking Water

❓What is a safe TDS level in RO water?

150–300 ppm is considered safe and ideal for drinking.

❓Is it okay to drink water with TDS below 50?

Occasionally, yes. But long-term consumption is not advisable without remineralization.

❓How can I increase TDS in my RO water?

Install a mineral cartridge, use a TDS controller, or blend with safe tap water.

❓Why does my RO water taste flat?

Because it has very low TDS, meaning it lacks minerals that enhance taste.

❓Can low TDS water harm children or elderly people?

Yes, especially if consumed long term, as it may lack essential minerals required for growth and health.

 Final Takeaway:

TDS less than 50 is not dangerous, but it’s not optimal either. Choose water that hydrates, nourishes, and balances—your health depends on it.