0 Exposure to Traffic Linked to Heart Attack

In June I posted an article that cited research describing how exposure to traffic and air pollution was especially unhealthful for people with diabetes:

Another Reason to Clean the Air

Heres a related study that appeared in the New England Journal of Medicine last October. It found that exposure to traffic just about tripled their subjects risk for heart attack within an hour.

Time spent in cars, motorcycles, bicycles, or on public transportation consistently increased the risk for heart attack. Again, people with diabetes were found to be more susceptible.

It may not be possible to change your commuting routine. But in light of research that suggests traffic and poor air quality can compromise cardiovascular health, coupled with the recent need for energy conservation, it may be wise to consolidate errands and limit trips when you can.

Also, as one commenter said:

"We cant avoid all pollution, but sufficient use of antioxidants and a healthy diet with proper exercise should help."

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For a summary of the study:
Sitting in Traffic Ups Risk of Heart Attack

For the study itself (abstract only, subscription required for full article):
Exposure to Traffic and the Onset of Myocardial Infarction

0 Modern Climate Control Linked to Weight Gain and Obesity

(Article first published as Is Your Warm House The Reason You Can’t Lose Weight? on Technorati.)

We are all well aware that eating too much and insufficient exercise are important factors that determine our weight and drive the current obesity epidemic. Weight gain and loss is a product of many other lifestyle factors including stress, sleep and even the temperature of your house. A review published in the journal Obesity Reviews examines the link between reduced exposure to the cold and obesity in the UK and US.

We Burn More Calories When Cold

It’s not something we think a lot about when we’re sitting in our favorite easy chair in front of a warm fire in our well insulated house during winter. We can easily control our environment with a turn of the thermostat. In fact, the only deterrent to staying warm for most people is fear of the fuel oil or electric bill at the end of the month.

Historically, humans have lived in cold climates where they had to endure bitter cold for extended periods. Our body must burn calories at a much higher level to keep us warm during these times, and the increased metabolism helps to prevent overweight and obesity. This study review attempts to explain that seasonal cold helps to regulate energy balance and can help maintain normal body weight on a population level.

Indoor Temperatures Have Increased Over the Past Several Decades

Widespread access to central heating and air conditioning contribute to a restriction of the temperature variations experienced under natural conditions. Humans have evolved to acclimate to mild thermal stress, as our metabolic rate can easily adjust to differing temperature zones. When we’re cold, our heart rate and blood pressure increase as blood vessels close to the skin constrict in response to reduced temperatures.

The net effect is more calories burned for a longer period of time and this translates into lower body weight. Researchers have found that we experience a much smaller range of temperature variation than we did just 30 years ago. While this may not fully explain the skyrocketing overweight and obesity rates now seen across the US and UK, it does provide an important clue to how our environment can impact our ability to maintain a normal weight.

External Temperature Can Modify Our Fat Structure

Over the past decade, medical researchers have gained a much better understanding about the two distinctly different types of adipose or fat cells that we accumulate. White fat is metabolically active tissue that accumulates most commonly around the hips and mid-section of the body. Excess amounts of white fat are associated with inflammation, metabolic disease, heart disease and cancer.

Brown fat is a thermally active type of tissue that actually burns calories for energy and is associated with a higher metabolic rate and lower weight range. Researchers from the Obesity Reviews study found that when people spend more time in a climate controlled environment they produce less brown fat and metabolize fewer calories at rest. This was found to result in a tendency to gain weight, especially when coupled with a sedentary lifestyle.

The researchers concluded "Research into the environmental drivers behind obesity, rather then the genetic ones, has tended to focus on diet and exercise -- which are undoubtedly the major contributors. However, it is possible that other environmental factors, such as winter indoor temperatures, may also have a contributing role. This research theore raises the possibility for new public health strategies to address the obesity epidemic." The bottom line is to caully control calories and remain physically active. Be mindful that external environmental factors also contribute to your ability to successfully lose weight.

0 Fast food diet linked to asthma and eczema severity in kids

Fast Food Diet Linked to Asthma and Eczema Severity in Kids, Large Study Finds


Eating three or more weekly servings of fast food is linked to the severity of allergic asthma, eczema, and rhinitis among children in the developed world, indicates a large international study published online in the respiratory journal Thorax.

The findings prompt the authors to suggest that a fast food diet may be contributing to the rise in these conditions, and if proved causal, could have huge implications for public health, given the popularity of these foodstuffs.

The authors base their findings on data from more than 319,000 13-14 year olds from 107 centres in 51 countries, and more than181,000 six to seven year olds from 64 centres in 31 countries.

All the participants were involved in the International Study of Asthma and Allergies in Childhood (ISAAC), which is a collaborative research project involving more than 100 countries and nearly two million children, making it the largest study of its kind.

The teens and the childrens parents were formally quizzed on whether they had symptoms of asthma (wheeze); rhinoconjunctivitis (which produces a runny or blocked nose accompanied by itchy and watery eyes); and eczema; and their weekly diet.

Questions focused particularly on the severity of symptoms over the preceding 12 months -- including frequency and interference with daily life and/or sleep patterns -- and certain types of food already linked to protective or damaging effects on health

These included meat, fish, fruits and vegetables, pulses, cereals, bread and pasta, rice, butter, margarine, nuts, potatoes, milk, eggs, and fast food/burgers. Consumption was categorised as never; occasionally; once or twice a week; and three or more times a week.

After taking account of factors likely to influence the results, the analysis showed that fast food was the only food type to show the same associations across both age groups, prompting the authors to suggest that "such consistency adds some weight to the possible causality of the relationship."

It was associated with current and severe symptoms of all three conditions among the teens -- across all centres in the participating countries, irrespective of gender or levels of affluence.

The pattern among children was less clear-cut, but a fast food diet was still associated with symptoms across all centres -- except for current eczema -- and poorer countries -- except for current and severe asthma.

And this difference might have to do with the fact that children have fewer options about their food choices, suggest the authors.

Three or more weekly servings were linked to a 39% increased risk of severe asthma among teens and a 27% increased risk among children, as well as to the severity of rhinitis and eczema, overall.

On the other hand, fruit seemed to be protective in both age groups across all centres for all three conditions among children -- both current and severe -- and for current and severe wheeze and rhinitis among the teens.

Eating three or more weekly portions was linked to a reduction in symptom severity of between 11% and 14% among teens and children, respectively.

The authors suggest that there are plausible explanations for the findings: fast food contains high levels of saturated and trans fatty acids, which are known to affect immunity, while fruit is rich in antioxidants and other beneficial compounds.

The authors emphasise that their results do not prove cause and effect, but they do warrant further investigation.

"If the associations between fast foods and the symptom prevalence of asthma, rhinoconjunctivitis and eczema is causal, then the findings have major public health significance owing to the rising consumption of fast foods globally," they conclude.