THE WATER STORY & HEART DISEASE
Source: HEALTHY WATER Martin Fox, Ph.D.
“Over the years many studies have been published on the relationship between drinking water and cardiovascular mortality.
Two beneficial factors continually stand out – hardness and total dissolved solids. Both have been associated with lower mortality from heart disease.
Hardness refers to the amount of calcium (Ca) and magnesium (Mg), or calcium carbonate in the water. The more Ca, Mg, or calcium carbonate, the harder the water, the less – the softer the water.
The first major study on drinking water and heart disease was in 1960 by Schroeder. In his paper, Relation Between Mortality from Cardiovascular Disease and Treated Water Supplies, the water in 163 largest cities in the United States was analyzed for 21 constituents and correlated to heart disease.
He concluded “some factor either present in hard water, or missing or entering in soft water is associated with higher death rates from degenerative cardiovascular disease.” In 1979 after reviewing fifty studies, Comstock concluded, “there can be little doubt that the associations of water hardness with cardiovascular mortality are not spurious.”
Too many studies have reported statistically significant correlations to make chance or sampling errors a likely explanation. Comstock suggests that the reason for this association is a “deficiency of an essential element or an excess of a toxic one.” Certainly a combination of both is also possible.
Today after thirty years of research we are left with Schroeder’s initial conclusion: drinking hard water results in less cardiovascular disease than drinking soft water.
Yet over the years we’ve seen several published reports analysing specific elements in drinking water and their possible relationship to heart disease. One researcher studies zinc, another copper, another selenium, and so on. And as you read this material, you disover an inconsistent and confusing picture. But, if you look at the broader picture, if you look at the studies on hardness, you will find very consistent results:
…the harder the water, the less heart disease deaths.
In most cases the harder the water, the more Ca and Mg is in the water. However several interesting studies indicate that Magnesium might be the more important of the two elements.
Professor Ragnar Rylader notes that studies in Switzerland, Germany and Sweden show that when the Magnesium in drinking water exceeds 10-15 mg/L, the rate of mortality falls in comparison to neighbouring communities with lower levels of Mg in the water. Some studies recommend 20 mg/L as the ideal Mg level. However, there are studies showing 6 to 8 mg/L is highly beneficial. Some bottled water manufacturers go so far to claim that 90 mg/L is best. At this time I do not believe that Mg is the all encompassing silver bullet that some claim. But I do believe it is important.
Knowing the levels of Ca and Mg in your drinking water is worthwhile.
Look at both the hardness levels and the specific amounts of Ca and Mg.
Before highlighting some of the major studies, let’s discuss TDS, (total dissolved solids). TDS is a measurement of all the minerals in drinking water. TDS not only includes calcium and magnesium (the hardness factors), but also zinc, copper, chromium, selenium and so on. Sauer analysed 23 drinking water characteristics in 92 cities (“Relationship of Water to the Risk of Dying”) and found people who drank water higher in TDS had lower death rates from heart disease, cancer, and chronic diseases than people who drank water with lower amounts of TDS.
Frequently, where the water is hard, the water is also high in TDS. Although most studies on heart disease have not looked at TDS, but only at hardness, this factor has been ever present and may be playing a very significant role.
The more we try to isolate and study the impact of individual minerals the more we can lose sight of the unifying, comprehensive, beneficial factors present in water like hardness, TDS, and pH. Perhaps one of the main reasons there are inconsistencies in the water story is simply because we are obsessed to locate a specific isolated element that is responsible for the beneficial effects of healthy drinking water.
Let’s look at some of the major studies.
In Great Britain, the British Regional Heart Study analysed 253 towns from 1969 to 1973. They found 10% to 15% more cardiovascular deaths in soft water areas than in hard water areas. They suggest that the ideal amount of hardness is approximately 170 mg/L (or ppm-parts per rnillion).
In the United States,
Greathouse and Osborne studied 4200 adults, ages 25 to 74 in 35 different geographic areas.
Their findings also showed less heart disease mortality in hard water areas than in soft water areas. A report by the Oak Ridge National Laboratory also found that the calcium and magnesium in hard water reduces the risks of heart attacks and strokes. It compared the health records of 11,400 Wisconsin male farmers who drank well water from their own farms. The farmers who drank soft water suffered from heart disease, whereas, the farmers who drank hard water were, for the most part, free of the problem.
Sometimes, the best experiments are those nature has been silently conducting for years.
Some of the most revealing water studies highlight two neighbouring towns in which one town alters its hard water to create a softer water. What are the results of this action? A higher rate of heart disease mortality.
We see this in the English towns of Scunthrope and Grimsby. Both towns drank the same water with 444 mg/L of hardness and had identical heart disease mortality rates. Scunthrope softened its water to 100 mg/L of hardness and within a few years a striking increase in cardiovascular deaths occurred. Whereas in Grimsby the rate was virtually the same as it had been. This pattern has also been reported in the Italian towns of Crevalcore and Montegiorgio and the Abruzzo region of Italy.
The National Academy of Sciences Conclusion:
“An optimum conditioning of drinking water could reduce the amount of cardio-vascular disease mortality by as much as 15% in the U. S. When looking at the research, two facts stand out.
- First, there is a definite relationship; a clear association between water hardness and heart disease mortality. We should try to drink water that has approximately 170 mg/L of hardness; the level found ideal in Great Britain.
- Second, there is a definite relationship between TDS and heart disease mortality. Higher levels of TDS results in less heart disease. Proper levels of hardness and TDS are two of the beneficial properties In drinking water constituting a healthy drinking water.