While choosing between bottled water and RO water, you might hear the term TDS a lot. If you’re someone who has little to no idea what it means, you might get confused hearing people’s opinions about drinking low TDS water.
So, does low TDS water have side effects? Low TDS water has very low percentage of essential minerals and drinking it for a long time might cause some negative effects if you are suffering from illness, hormonal issues, or other health problems. Otherwise, it is completely safe for a healthy individual.
What Does Low TDS Drinking Water Refer to?
Total Dissolved Solids or TDS is the measurement of the total concentration of elements dissolved in pure water other than H2O molecules. Most dissolved substances are inorganic salts, while some are organic materials.
As water is a universal solvent, it dissolves almost all types of soluble materials and creates total dissolved solids.
So, TDS are present almost everywhere, from natural water springs to chemically treated municipal water supplies. TDS levels give a general idea of what the water tastes like and whether or not it should be consumed.
TDS level of water is measured in mg/L or PPM (Parts Per Million). According to the World Health Organization (WHO), the acceptable TDS levels in drinking water are 300 ppm for the human body. Over 1000 ppm of TDS in water isn’t safe for human consumption.
TDS level between 0 to 250 ppm is considered low, and low TDS water has a very low amount of dissolved substances, including essential minerals.
Here’s a comparison chart that will help you understand how the drinking water quality changes depending on the TDS level
| TDS Level | Water Quality |
| 0 – 250 ppm | Low; Lacks minerals like Sodium, Calcium, Magnesium, etc. |
| 300 – 500 ppm | Ideal for drinking |
| 600 – 900 ppm | Not great; Might contain harmful contaminants |
| 1000 – 2000 ppm | Bad; Polluted might have an unpleasant smell |
| >2000 ppm | Unacceptable |
Possible Health Effects of Drinking Low TDS Water
Due to the lack of minerals in low TDS water, drinking it regularly can negatively affect your body’s homeostasis increasing the risk of gastrointestinal troubles, chronic kidney disease, high blood pressure, cardiovascular disease, etc. Plus, it will change the taste, smell, and water quality.
1. It Changes the Taste of Drinking Water
When it comes to taste and mouthfeel, both low and high TDS water is undesirable. High TDS water running in the water pipes will taste salty and bitter, while low TDS water has a flat, diluted taste that most people don’t like.
Moreover, when you use this water for cooking and brewing coffee, tea, or other drinks, the end result isn’t very good, and the taste is not as good as it should be. If you’re cooking red meat, it’s recommended to use mineral water instead to complete the flavors of your food.
2. Low TDS Water Might Have Some Negative Effects on Your Kidney
Since Kidney is the main part of our body that maintains the balance of water and electrolytes, it’s most at risk to be harmed by the low mineral content of drinking water. As mentioned, TDS includes both organic and inorganic compounds such as Calcium, Chloride, Magnesium, Potassium, Copper, Zinc, Aluminum, Lead and Arsenic.
Some of these heavy metals and trace elements are obviously harmful to your health, and water purifiers or reverse osmosis systems filter them out to give you clean water.
However, during the filtering process, some water purifiers separate the essential minerals like Calcium and Magnesium. As a result, low TDS water can lead to a 20% reduction in sodium, magnesium, and other mineral concentrations.
This imbalance in the mineral levels will have a negative effect on your kidneys, causing chronic kidney diseases. If you already have kidney disease, the situation might get worse.
3. Low TDS Water Can Affect Your Overall Health
Drinking low TDS water from reverse osmosis or other water sources for a long time can have health effects on your body. According to WHO, drinking water should contain 3 ppm of beneficial calcium, 10 ppm of magnesium, 30 ppm of bicarbonate ion, and 10 ppm of dissolved salts.
As low TDS water doesn’t meet this standard amount of minerals, minor illnesses related to these minerals might appear. For example, a lack of Calcium will lead to bone, muscle, and dental sickness. It can also affect your blood pressure.
Similarly, lower Sodium levels might interrupt the functions of your nervous system. Bicarbonate and Chloride deficiency will harm the pH buffering system of our body resulting in low pH or high pH levels of your body fluid.
Keep in mind that, most of the minerals in our body come from the food we consume. So, if you maintain a balanced diet, none of these will happen to you even when you keep drinking low TDS water for months.
