Energy Drinks

Energy drinks have become extremely popular with students.  The question has always been, are they safe?

Well, millions of cans have been sold and there is little documentation of health related issues.

A new study by Leah Steinke and colleagues in the Annals of Pharmacotherapy, however, has raised some concerns about the effect of energy drinks on the cardiovascular system.  

In this study fifteen people were given two energy drinks each day (100mg taurine and 100mg caffeine) for seven days.  Their blood pressure, heart rate and electrocardiographic (ECG) characteristics were measured prior to the study and then on Day1 and Day 7 over a few hours following consumption of the energy drinks.

Steinke and colleagues found that while there were no statistically significant affects associated with the ECG characteristics, the same could not be said for heart rate or blood pressure.  Heart rate was up 11% on Day 7 and blood pressure also increased.  Systolic pressure(i.e., the 'high' number in a blood pressure reading) was up 9.6% and the diastolic pressure (i.e., the 'low' number in a blood pressure reading) was up 7.8%.

Is this concerning?  Probably not for young healthy adults, however, for those with underlying but undiagnosed heart problems or high blood pressure, this could be very concerning. Especially with long term consumption.  These products clearly push the cardiovascular system in a direction that is unhealthy.

Caveat: this study was small (15 people) and the baseline health data was taken only immediately prior to the study.  Longer monitoring of the baseline data would help to determine just how much variability was natural for this small group.

Photo Credit: Grendelkhan, Wikipedia commons.

Research citation: Steinke L, et al. 2009. Effect of "Energy Drink" consumption on hemodynamic and electrocardiographic parameters in healthy young adults.  Annals of Pharmacotherapy 43(4): 596-602.

A Better Way to Identify Healthy Food

How can you communicate nutrition information to a public that usually does not know the difference between the major macronutrients (carbohydrates, lipids, and proteins)?

The answer might be to use a system that everyone already understands, traffic lights. Bridget Kelly and colleagues have just published some research (Health Promotion International 2009) looking at how well the public understands nutrition related labelling of food products.  

The traffic light system uses the colours green, amber and red to identify food components that are good, fair, and poor respectively.  An additional traffic light provides the overall health rating of the food.  It seems easy to understand even at a glance.

Kelly and colleagues found that consumers were 3 times more likely to identify healthy foods using the traffic light system as compared to a colour coded Daily Intake label and 5 times more likely when using a monochrome Daily Intake system.

Short story: a simple, broadly understandable system that works.

Nerd alert:  Kelly and colleagues used logistic regression to come to the conclusions given above. Reading through their methods section I can't say I'm totally happy with the technique used to identify model variables for the regression.  They should have used either a more a priori technique or gone with a stepwise logistic regression.  

Photo credit: www.choice.com.au

Blurring Unemployment Statistics

Above are the unemployment statistics for the Cariboo over the past 15 months.  Currently, the Cariboo has the second highest unemployment rate in the province, second only to the North Coast-Nechako which has unemployment at 11.1%.

Is unemployment in the Cariboo currently 10% as suggested by these data above from BC Stats? No, not really.  These numbers, while indicated for specific months, are actually averages of the previous three months.  Statistians use three month averages to smooth out their data--everyone wants a smooth graph right?  Graphs that show gradual transitions make politicians less likely to hyperventilate and the public to panic.

Unfortunately, occasionally this does not reflect the situation in the real world.  This is one such occasion.

Data Source: Labour Force Statistics: BC Stats.  Plotted by me.