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Health news:
June 2010 - Dec 2013

Minimizing breast cancer risk

May 2010

Time to move beyond salt ?

Salt hypothesis vs. reality

Is sodium bad?

April 2010

Salt studies: the latest score

From Dahl to INTERSALT

Salt hypothesis' story

March 2010

Salt war

Do bone drugs work?

Diabetes vs. drugs, 3:0?

February 2010

The MMR vaccine war: Wakefield vs. ?

Wakefield proceedings: an exception?

Who's afraid of a littl' 1998 study?

January 2010

Antibiotic children

Physical activity benefits late-life health

Healthier life for New Year's resolution


December 2009

Autism epidemic worsening: CDC report

Rosuvastatin indication broadened

High-protein diet effects


November 2009

Folic acid cancer risk

Folic acid studies: message in a bottle?

Sweet, short life on a sugary diet


October 2009

Smoking health hazards: no dose-response

C. difficile warning

Asthma risk and waist size in women


September 2009

Antioxidants' melanoma risk: 4-fold or none?

Murky waters of vitamin D status

Is vitamin D deficiency hurting you?


August 2009

Pill-crushing children

New gut test for children and adults

Unhealthy habits - whistling past the graveyard?


July 2009

Asthma solution - between two opposites that don't attract

Light wave therapy - how does it actually work?

Hodgkin's lymphoma in children: better alternatives


June 2009

Hodgkin's, kids, and the abuse of power

Efficacy and safety of the conventional treatment for Hodgkin's:
behind the hype

Long-term mortality and morbidity after conventional treatments for pediatric Hodgkin's


May 2009

Late health effects of the toxicity of the conventional treatment for Hodgkin's

Daniel's true 5-year chances with the conventional treatment for Hodgkin's

Daniel Hauser Hodgkin's case: child protection or medical oppression?

April 2009

Protection from EMF: you're on your own

EMF pollution battle: same old...

EMF health threat and the politics of status quo

March 2009

Electromagnetic danger? No such thing, in our view...

EMF safety standards: are they safe?

Power-frequency field exposure

February 2009

Electricity and health

Electromagnetic spectrum: health connection

Is power pollution making you sick?

January 2009

Pneumococcal vaccine for adults useless?

DHA in brain development study - why not boys?

HRT shrinks brains


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July 2007

Is your exercise healthful?

How healthful is exercising in polluted air? New York Times article by Gretchen Reynolds gives you good reasons to take this question seriously. Recent studies seem to be positively linking outdoor air pollutants - in particular "fine particulates" (soot) - not only to respiratory system ailments, but also to increased risk of heart attack.

The American Hearth Association acknowledged this in 2004.

While exercising, you take in up to 20 times more air than sedentary person. This effectively increases body exposure to any toxin, or pollutant present in the air by as much. In other words, what is normally considered to be safe level of pollution,

can easily turn into dangerous and harmful while exercising.

For instance, the maximum safe PM2.5 (particles smaller than 2.5 microns) standard, as 24-hour average, is set by the Environmental Protection Agency (EPA) at 15μg/m3. At 15-fold the sedentary air intake, it effectively becomes 225μg/m3, considered by the EPA to be "unhealthy" 1-hour average, and quite close to the "very unhealthy" level, beginning at 250μg/m3

How this dramatic effective increase in air pollution due to exercising may affect your health depends on several factors, including your air quality level, frequency, duration and intensity of exercise, as well as your individual vulnerability. While short-term effects shouldn't be worrisome for most folks, long-term effect is a big unknown. Even the EPA's safe level is not tested long-term, and may not be harmless for all.

It may parallel, say, vitamin C DRI (~100mg/day), which is pretty much guaranteed to safeguard you from scurvy, but puts your health at a serious risk from compromising your health, being grossly below the longer-term optimum, estimated at anywhere from 400mg to 5 grams a day.

And those exercising indoors are not out of the woods either. In fact, indoor air is on average 5-10 times more contaminated than outdoor air. Air-purifiers are efficient for larger particles, but most become increasingly inefficient as the particle size goes below 0.1μ (they can be smaller than 0.01μ). And it is

exactly those smallest particles -

so called "ultra fine" and "nano" particles - that can penetrate through the lungs into the blood, with the potential of causing, or contributing to vasoactive (constriction/dilation) and atherosclerotic blood vessel changes.

Considering high average level of indoor air contamination,

indoor exercising is probably more unhealthy

than outdoor's, despite the use of air-purifying systems. Special concern are commonly high levels of the volatile organic compounds.

In conclusion, we simply cannot ignore air quality, even for our regular daily activities, and especially when it comes to regular exercise. Exercising in heavily polluted air is highly undesirable, and can't be considered healthful. The problem for many is that the air is polluted in their wider area. In such case, it is recommendable to adjust (scale down) exercise frequency and intensity according to the pollution level.