Why I Switched to Reverse Osmosis Water (And How to Remineralize It Properly)
RO water removes virtually all contaminants, including the ones that matter for longevity. But it also strips minerals. Here's the full setup I use and why it's worth the investment.
Water is the most fundamental input to your biology, and most people give it zero thought. They drink whatever comes out of the tap or buy the plastic bottle from the gas station fridge, and that’s it.
I was the same way until I started looking at what’s actually in municipal tap water, and realized that “passes EPA standards” and “optimal for human health” are not the same thing.
What’s in Tap Water That Shouldn’t Be
Let me be specific, because “tap water is bad” is often vague and alarmist. Here’s what’s actually documented:
Chlorine and chloramines: Added to kill pathogens. Necessary in the distribution system. Not something you need to ingest in your drinking glass, as chlorine forms disinfection byproducts (DBPs) like trihalomethanes (THMs) that are associated with bladder cancer risk in epidemiological studies.
Fluoride: Added to most US municipal supplies for dental health. Effective topically. The systemic benefits of ingested fluoride are disputed, while concerns about fluoride’s effects on thyroid function and neurodevelopment at higher doses are real and documented in the literature. Even if you support fluoridation, filtering it out and using fluoride toothpaste gives you the dental benefit without the systemic exposure.
Lead and other heavy metals: Old infrastructure leaches lead from pipes into water. The Flint crisis was extreme, but lower-level lead contamination is common in older housing stock. Lead has no safe level of exposure, particularly in children.
PFAS (forever chemicals): Per- and polyfluoroalkyl substances are in many US water supplies. These are essentially indestructible organic compounds linked to cancer, thyroid disruption, immune suppression, and hormonal effects. Standard filters don’t remove them.
Microplastics: Now documented in tap water globally. The health implications are still being studied, but the trajectory of the research is not reassuring.
Agricultural runoff: Nitrates, atrazine, and other herbicides and pesticides are commonly detected in water supplies in agricultural areas.
Why Reverse Osmosis Is the Standard
Reverse osmosis forces water through a semi-permeable membrane with pores of approximately 0.0001 microns. For reference:
- Microplastics: 1–5 microns (fully removed by RO)
- Most bacteria: 0.2–2 microns (removed)
- Viruses: 0.02–0.3 microns (most removed)
- Heavy metals, PFAS, fluoride, nitrates: all removed by RO membranes
No other consumer filtration technology approaches this breadth of removal. Carbon block filters are excellent for chlorine, some VOCs, and improving taste, but they don’t remove fluoride, heavy metals, PFAS, or microplastics.
A five-stage RO system under the sink produces filtered water at pennies per gallon and removes 95–99% of every contaminant on the list above. It’s the single biggest upgrade you can make to your daily water quality.
The One Downside: RO Removes Minerals
Pure RO water is slightly acidic and completely mineral-free. This is where most people stop the conversation, but you need to understand why it matters and what to do about it.
Magnesium and calcium dissolved in water contribute meaningfully to daily mineral intake. “Hard” water has long been associated epidemiologically with reduced cardiovascular risk. The mineral content is likely part of why.
Drinking large quantities of completely demineralized water can also, over time, leach minerals from tissues, though this requires very high volume intake and is rarely a clinical issue for most people.
The solution: remineralize
This is the critical step that most people skip. After filtering, I add trace minerals back.
Option 1: Ionic trace mineral drops. ConcenTrace and similar products are concentrated mineral solutions derived from natural sources. 10–30 drops per liter of water adds a full spectrum of ionic trace minerals. This is what I use daily. Taste is slightly salty at higher doses. I use 20 drops per liter, which is barely perceptible.
Option 2: Himalayan or Celtic sea salt. A tiny pinch (1/8 tsp) per liter adds electrolytes and trace minerals. Simple and effective, though not as comprehensive as mineral drops.
Option 3: A remineralization filter stage. Many RO systems can be fitted with a sixth-stage remineralization cartridge that adds calcium and magnesium back. This is the most convenient option if you don’t want to add drops manually.
My Complete Water Setup
Here’s exactly what I use:
Filtration: APEC 5-stage under-sink RO system. Filters last 6–12 months and are inexpensive to replace. The membrane lasts 2–3 years.
Storage: I fill 1-gallon glass dispensers directly from the RO tap. Glass ensures zero leaching after filtration. The whole point of filtering the water is defeated if you store it in plastic.
Remineralization: 20 drops of ConcenTrace per liter, added directly to the glass dispenser.
Daily intake: I aim for about 2.5–3 liters per day. With the mineral drops, I’m hitting my magnesium and electrolyte targets from the water itself, which reduces the need for separate electrolyte supplementation.
What About Bottled Water?
Bottled water is not a solution. It’s a problem wrapped in another problem.
The better brands (Evian, Volvic, Mountain Valley) have consistently low contaminant levels and reasonable mineral content. But they come in plastic, and plastic water bottles are one of the most significant sources of microplastic and endocrine-disrupting chemical exposure.
If you travel and don’t have access to filtered water, the best options are:
- Glass-bottled still water (Voss, Mountain Valley in glass)
- Canned water (aluminum, lined with BPA-free coating)
- A portable carbon filter (Grayl, LifeStraw) for reducing the worst contaminants until you’re back home
The ROI on Clean Water
An under-sink RO system costs $150–250 upfront and about $50/year in replacement filters. If you’re currently buying plastic-bottled water, you’re likely spending more than this already, and getting a worse product.
Water is the substrate your entire biology runs on. Every cellular process, every nutrient absorption, every detox pathway requires it. The quality of your water supply is not a minor variable. It’s about as fundamental as it gets.