Some researchers claim they’ve found a way to combat diseases and enable space travel using… “light water”! You couldn’t tell the difference between tap water and deuterium-depleted water, but the other one is promoted to protect against cancer, radiation, and more. In the absence of solid evidence, however, DDW looks like just another fad.
What is Deuterium-Depleted Water?
A water molecule contains 2 atoms of hydrogen and 1 atom of oxygen (H2O).
Hydrogen exists in different forms, called isotopes, depending on the number of neutrons – neutral particles – in its core. The isotope without neutrons (H – protium) is the most abundant, but water molecules also contain a small amount of deuterium (D or hydrogen-2).
Deuterium, having 1 neutron, is about 2 times heavier than regular hydrogen. Thus, we call water with reduced deuterium content “light water” or deuterium-depleted water (DDW).
- Temperature – warm waters contain more deuterium
- Altitude – high mountain waters contain less deuterium
- Source – freshwaters contain less deuterium than oceans
- Latitude (distance from the equator) – water on the poles has the least deuterium
A standard concentration of deuterium in water is 150 ppm (parts per million) or 1 atom of deuterium per 6400 atoms of regular hydrogen. In other words, each quart (or liter) of water contains only a few drops with deuterium [3, 4].
- Stimulates cell growth and recovery
- Boosts detox and metabolism
- May have anticancer effects
- May support mood and cognition
- May protect the liver and heart
- Not well researched
- Most studies are biased
- May be toxic to stem cells
- Production is expensive and energy-consuming
How Does It Work?
- Energy production and metabolism
- Detox pathways
- Antioxidant protection
Based on studies on bacteria, it might also work by triggering hormesis – acting as a mild stressor that increases resilience to bigger stressors and enhances performance. This is still largely speculative, though, as it relies on the response of bacteria, not humans .
Manufacturers and retailers claim deuterium-depleted water can treat diabetes and high blood pressure, enhance sports performance and strength, and combat the effects of stress and aging. However, solid clinical evidence supports none of these claims.
Health Effects of Deuterium-Depleted Water
Limitations and Caveats
Research on deuterium-depleted water (DDW) is scarce. Most health benefits are limited to a couple of animal or cell studies, and we can’t draw solid conclusions from them.
- Lack of a control group that would eliminate the impact of ‘normal’ water and the placebo effect
- Suspicious randomization
- Small sample size
- Vague interpretation of results
One team of Hungarian doctors have conducted the majority of clinical and animal trials on DDW and cancer. Some of them are involved in DDW commercial production and marketing, which points to a massive conflict of interest [5, 15, 14, 4, 16].
Deuterium-Depleted Water and Cancer
Although clinical studies on potential anticancer effects of DDW exist, many of them suffer from glaring flaws. These studies should guide further investigation but shouldn’t be interpreted as supportive of the anticancer effects until more research is done. Deuterium-depleted water isn’t approved for cancer prevention or treatment.
In a clinical study of 44 patients with prostate cancer, the addition of deuterium-depleted water (DDW) to standard treatment :
- Increased the chance of partial treatment success by 7 (7 vs. 1 patient)
- Reduced prostate volume
- Relieved unpleasant urination symptoms
- Cut the levels of PSA, a marker of disease progression
- Increased 1-year survival 4.5 times (2 vs. 9 deaths)
The same study observed 91 prostate cancer patients (46 with metastases) who consumed deuterium-depleted water. Their average survival time was 11 years, but, due to the lack of a placebo control, it’s unsure whether DDW contributed to the results .
Although the above study had flaws, it did include a control group that drank equal amounts of regular water. Both groups also received the same conventional treatment.
In another clinical trial, 129 patients with lung cancer consumed deuterium-depleted water along with their conventional treatment (chemo and radiation). On average, they survived 2-4 longer than expected, especially female patients (74 months vs. 26 months) .
However, this study did not include a control group that drank regular water. Strong placebo effects are a possibility.
An observational study followed 232 women with breast cancer who replaced “normal” water with deuterium-drinking water (DDW) for at least 3 months. Patients in the early stage survived 18 years on average, but most patients with metastases didn’t reach a 5-year survival. Those who took at least 2 rounds of DDW treatment (>6 months) survived the longest (~24 years) .
According to one review of clinical trials, drinking deuterium-depleted water could :
- Block the growth of cancer cells
- Prolong the survival of patients
- Improve their quality of life
All of the above studies have small samples and other serious flaws we already discussed.
One review of animal studies revealed that deuterium-depleted water (DDW) could kill cancer cells and fight different types of cancer in dogs, cats, and lab animals .
- Blocked cancer-promoting genes
- Eliminated or reduced the tumors
- Increased the animals’ lifespan
In test tubes, deuterium-depleted water also prevented the growth of different cancer cells. However, these findings have no clinical value, and they don’t imply actual anticancer effects in the human body [4, 18, 17, 19, 20, 21].
The above findings point to the anticancer potential of deuterium-depleted water, but they are far from conclusive. Well-designed clinical trials should examine this further.
Animal and Cell Research (Lacking Evidence)
No clinical evidence supports the use of DDW for any of the conditions listed in this section. Below is a summary of the existing animal and cell-based research, which should guide further investigational efforts. However, the studies listed below should not be interpreted as supportive of any health benefit.
Deuterium-depleted water (DDW) was able to protect mice from the damaging effects of radiation and increase their chance of survival .
In cell experiments, deuterium-depleted water strengthened and repaired DNA, protecting it against radiation-induced damage .
Theoretical anticancer and radioprotective effects of deuterium-depleted water may improve cancer treatment response but also enable future space travel.
Any astronauts venturing to Mars would be exposed to extreme levels of radiation in the flight, and high deuterium levels on the planet. Some scientists think that ensuring a deuterium-depleted water supply may play a crucial role in protecting the crews from cancer in future space missions to Mars [25, 26].
2) Liver Protection and Detox
- Repair oxidative damage in the liver
- Boost the production of protective compounds, such as glutathione
- Decrease the levels of inflammatory molecules (COX-2, PGE2)
- Prevent liver infection and injury
- Boost detox pathways
3) Mood & Memory
In a study on mice, deuterium-depleted water (DDW) reduced signs of depression and stress. Interestingly, it stimulated the brain’s memory center and increased wakefulness. These effects were similar to SSRI (antidepressant) drugs .
In rats, drinking deuterium-depleted water enhanced long-term memory, but it didn’t impact short-term memory and movement .
4) Diabetes and Heart Disease
In healthy rats, researchers tested the ability of DDW to :
In rats with high blood pressure, however, it only slightly increased insulin production. More research is needed to clarify these effects.
DDW Side Effects & Precautions
Keep in mind that the safety profile of deuterium-depleted water is relatively unknown, given the lack of well-designed clinical studies. The list of side effects below is not a definite one, and you should consult your doctor about other potential side effects, based on your health condition and possible drug or supplement interactions.
In the US, you may report drug or supplement side effects to the FDA at 1-800-FDA-1088 or at www.fda.gov/medwatch. In Canada, you may report side effects to Health Canada at 1-866-234-2345.
However, in one cell study, deuterium-depleted was toxic to human stem cells in the long run. This study confirmed that the best way to store stem cells is an environment with typical deuterium levels .
Studies haven’t evaluated the safety of deuterium-depleted water in childhood, pregnancy, and lactation. These sensitive groups should stay on the safe side and avoid it.
Safety for Pets
In different animal studies, deuterium-depleted water had no significant side effects. It was also safe for cats and dogs. In Hungary, deuterium-depleted water is a veterinary addition to cancer treatment. However, the available evidence is scarce [5, 28, 30, 4].
Products & Dosage
Deuterium-depleted water has not been approved by the FDA for medical use. In general, regulatory bodies aren’t assuring the quality, safety, and efficacy of supplements and similar dietary products. Speak with your doctor before taking DDW..
Only a handful of brands manufacture and distribute deuterium-depleted water. It’s available in 0.5-1.5L bottles with different deuterium concentrations (25-125 ppm). Prices range from $4 to $20 per liter, with lower concentrations of deuterium being more expensive.
The below doses used in clinical trials may not apply to you personally. If your doctor suggests using deuterium-depleted water, work with them to find the optimal dosage according to your health condition and other factors.
In clinical trials, cancer patients replaced their daily water intake with deuterium-depleted water (DDW). Doctors calculated the exact dosage depending on patients’ body weight and the concentration of deuterium in DDW [6, 15+, 14].
The range that will make water “low” in deuterium (D) is quite broad – from 1 to 120 ppm D. Some clinical studies used water with 10-20 ppm D, another gradually decreased deuterium content from 105 to 25 ppm, while the remaining one used water with 65-105 ppm D. In comparison, regular water contains ~150 ppm D [6, 15+, 14].
Deuterium-Depleted Water Production
Deuterium-depleted water is a byproduct of “heavy water” (D2O) production. Heavy water has applications in organic chemistry, drug development, and nuclear reactors.
Mass production requires complex distillation, electrical, or chemical reactions. Up to date, all methods are expensive, consume much energy, and pollute the environment. The so-called Girdler Sulfide (GS) process is the most efficient, but it uses toxic chemicals.
A team of Chinese scientists reported a new energy-efficient method that may improve the production of deuterium-depleted water in the future .
Can You Make Your Own?
Deuterium-depleted water (DDW) boils and freezes at slightly higher temperatures than regular water. In theory, you could use this feature to make DDW with partial distillation or freezing: water with deuterium would evaporate slower or freeze faster .
Given that 1 liter of tap water contains only a few drops with deuterium, it’s practically impossible to separate it and make DDW on a small scale.
Deuterium concentration in natural water is about 150 ppm (parts per million), which equals a few drops per liter. Deuterium-depleted water, also known as light water, contains less deuterium (1-120 ppm).
A couple of clinical trials have shown the anticancer potential of DDW, but they all had serious design flaws. There’s insufficient evidence for liver protection, cognitive and mood support, heart disease, and detox. In Hungary, veterinarians use it as a complementary cancer treatment for pets.
There’s no clinical evidence to support any of the potential uses and marketing claims about DDW.