Tuesday, November 18, 2014

Are Bicycle Lanes Good for Bicyclists?


Researchers have just found that designated bicycle lanes do not effectively increase the distance between a passing car and the bicyclist.

This recent study in an urban environment found that there are more significant variables than the presence of a bicycle lane that affects the overtaking distance between vehicle and bicycle. These important factors are:
  • Absolute width of the road
  • Nearside parking
  • Opposing vehicle traffic
Not surprisingly, the authors identified a larger "unknown factor" that affected how wide of a margin the driver gave the bicyclist. And that factor is (drum roll)..... the driver.

So, what can be done? Possible ways to improve bicycle safety in traffic include:

  • Make roads wide enough to handle both vehicle and bicycle traffic
  • Promote a driving culture that respects bicycle riders
  • Limit parking to side-streets

Cycle Lanes: Their Effect on Driver Passing Distances in Urban Areas

TransportVolume 29, Issue 3, 2014Special Issue: Special Issue on Travel Demand Management

Saturated Fats Bad, Polyunsaturated Fats Better

A recent study from Sweden and published by the American Heart Association has found that a diet rich in saturated fats leads to an unhealthy balance in serum cholesterol levels, whereas polyunsaturated fats have a more beneficial response. J Am Heart Assoc. 2014; 3: e001095

Comment: there are two important issues to consider when evaluating this study. First, adding polyunsaturated fats to the diet tends to lead to weight gain, which in most people will lead to excess weight gain. So, it is important to substitute polyunsaturated fats for calories coming from other sources. Secondly, it  does appear that saturated fats are not very good for you. Based on this study, here's a brief list of the "bad" fats (saturated) and the "better" fats (polyunsaturated).

  • most come from animal sources including meat and dairy products
  • fatty beef
  • lamb
  • port
  • poultry with skin
  • butter
  • most cheeses
  • dairy products made with whole or 2% reduced fat mil.
  • palm oil, coconut oil
  • OILS: soybean, corn, sunflower
  • some fish oils (salmon, mackerel, herring, trout)
  • walnuts, sunflower seeds
  • tofu
  • soybeans
  • flaxseed
 Now, what about "mono" unsaturated fats? These might be the best kinds of dietary fats, but at least they are considered to be better than saturated fats.

  • OILS: olive, canola, peanut, safflower, and sesame
  • Avocados
  • peanut butter (check the label)
  • many nuts and seeds, e.g. macadamia, hazelnuts, pecans, almonds, pistachios, cashews
  • certain types of margarine
  • cheeses: roquefort, monterey jack, parmesan
  • eggs (mostly good fats but also contain saturated fat)

  • Regular exercise and a stable, healthy weight are very important. 
  • High sugar foods are almost always "BAD"

Thursday, November 6, 2014

Colorectal cancer prevention by an optimized colonoscopy protocol

METHODS: retrospective cohort study of an optimized colonoscopy protocol: 
  • telephonic reinforcement of bowel preparation instructions; 
  • active inspection for polyps throughout insertion and circumferential withdrawal; and 
  • timely updating of the protocol and documentation to incorporate the latest guidelines. 
RESULTS: 17,312 patients underwent screening colonoscopies by 59 endoscopists in South Carolina, USA. Over 78,375 person-years of observation, the colorectal cancer mortality reduction was 89% (p < 0.001; four CRC deaths vs. 35.95 expected). 

CONCLUSION: Over 80% reduction in colorectal cancer incidence and mortality is achievable in routine practice by implementing key colonoscopy principles targeting near-complete polyp clearance.

Int J Cancer. 2014 Sep 20. doi: 10.1002/ijc.29228.