For a full explanation of our decision, click here.

The RSS feed has been updated, so subscribing to our feed here on Scienceblogs will still bring you all of the content at our new home.  If you experience any problems with the feed, please don’t hesitate to contact us by email, twitter, or by leaving a comment on either site.

I would just like to say that aside from the past week, our time here at Scienceblogs has been extremely positive thanks to the terrific readers here at Scienceblogs and to our former sciblings.  Thanks especially to Abbie from ERV and Scicurious (formerly of Neurotopia), for openly campaigning for our addition to the network, as well as Bora Zivkovic and Dave Munger for their advice during the move. 

Thanks again, and we hope you will continue the discussion at our new digs.

Travis

Last year I posted results from a study which suggest that having a breakfast high in fibre may be more satiating for a smaller number of calories, and thus may be one important way to help manage hunger and thus caloric intake. Today I came across another new study which suggests that a breakfast high in fibre and with a low glycemic index (the degree to which an ingested food causes a spike in blood glucose levels) may enhance fat oxidation during a subsequent bout of exercise.

Peter

Stevenson, E., Astbury, N., Simpson, E., Taylor, M., & Macdonald, I. (2009). Fat Oxidation during Exercise and Satiety during Recovery Are Increased following a Low-Glycemic Index Breakfast in Sedentary Women Journal of Nutrition, 139 (5), 890-897 DOI: 10.3945/jn.108.101956

This post was originally published on Obesitypanacea.com on April 23, 2009.

This is a hugely important issue, so hopefully we’ll get back to it ASAP here on Obesity Panacea.  But not this week.

Time to get outside and enjoy the sunshine!

Travis

Today we have Scibling Showdown # 2 – the pros and cons of grad school.  This episode includes Jason Goldman of the Thoughtful Animal, Christie Wilcox of Observations of a Nerd and Scicurious of Neurotopia.  We talk about how we chose our current labs, things we wish we had known before we started grad school, and where we plan to end up (spoiler: none of us have any idea!). 

We also discuss how blogging plays into the graduate school experience, and here it sounds like we’ve all had overwhelmingly positive experiences.  I think any student will admit that grad school is a bit bipolar – periods where everything is going amazingly smoothly, followed by rough patches where nothing seems to go the way you want.  It can get especially tough in the final stages of a thesis, when you have spent literally months writing and re-writing the same few pages of text.  Performing revision after revision (after revision) on a manuscript, only to have it rejected, can also put you into a bit of a funk.  Blogging is a great way to stay excited about research, since you only have to discuss the papers that you think are interesting!  I can’t say enough about the ways that blogging has enriched my graduate school experience, and it seems that almost every other blogger I talk to has had a similar experience. 

The other feeling I got from the discussion was that although grad school has its ups and downs, we all seem to generally enjoy the experience.  I know I wouldn’t still be in school if I didn’t really enjoy it!  Grad school sometimes gets a bad rap, but it really is a lot of fun when you find the right lab.

Jason, Christie, and Scicurious are all cross-posting the podcast today, so I’d encourage you to check out their sites to see their thoughts on our discussion.  We’re hoping to make these chats a semi-regular feature, so any comments or suggestions would be greatly appreciated.  I know that there are quite a few grad students/former students that read our blogs as well, and it would be great to hear about your experiences.

To listen to the podcast, you can use the audio player below, or download the podcast itself by clicking here.  And don’t forget that you can also subscribe in iTunes to have all of our
future podcasts delivered directly to your ipod.

Enjoy the podcast!

Travis

Happy Canada Day!  It looks like a pretty nice day here in the capital as well as the rest of the country – a great chance to get in some physical activity with your friends and family!  Enjoy the long weekend!

Travis

Today is the first day of summer vacation here in Ontario, and I assume that the summer break has begun in most other parts of North America as well.  That means that millions of kids are looking at 8 gloriously school-free weeks in July and August.  Now while physical activity promotion folks like myself would hope that all of these kids are going to spend their summer outside being physically active, there is plenty of evidence to suggest that that is not the case for most kids. 

Since these are kids, parents obviously have a huge amount of control over the way they spend free time.  So what do parents look for when making summer plans for their kids?  According to a new survey by the Heart and Stroke Foundation of Ontario/Environics, physical activity doesn’t play into the decision making process for most parents. 

When asked to name the biggest challenge to making summer plans for
their kids, 49% of parents in the Greater Toronto Area named
affordability, while just 17% said it was ensuring that the child was
physically active.  Now I don’t think that anyone is surprised that the
primary concern would be affordability, but physical activity was literally
the bottom of the list, well below other concerns including safety,
that the program be beneficial for the child in some way, or simply
knowing what programs are available.  Now we could interpret this a few
ways – perhaps finding summer activities that involve physical activity
isn’t a challenge because there are so many opportunities that involve
physical activity.  But again, given the low levels of physical activity
being performed by Canadian children, that seems unlikely.  What seems
more likely is that physical activity just is not the primary (or
tertiary, or even quaternary (?)) concern for most parents.  That
doesn’t mean that parents deserve all the blame, but it’s still an
interesting statistic.

After the release of the survey I had the
opportunity to discuss the results with Sharon Brodovsky (at left) from
the Heart and Stroke Foundation.  I find it very interesting and
frustrating that the solutions to these issues seem so incredibly simple
(e.g. take your kids to the park), and yet childhood physical activity
levels still don’t seem to be improving.  That’s one of the reasons why I
like Sharon’s Spark
program, since it focuses explicitly on advocacy and creating a
societal movement for healthier children, rather than placing all of the
burden on parents (for my earlier post on Spark, click here).  If you only have time to read one answer, jump to
number 6, as I that’s the one that I found by far the most interesting,
and the most important for those of us promoting physical activity.

Enjoy
the interview!

Travis

————————————————

1. 
Affordability was the number one concern in your survey.  If a parent
can’t afford to send their kid to camp, what practical steps can they
take to make sure their child has a physically active summer? 

There
are many options in the city that are free. Playing in their
backyard, local parks, accessing local city outdoor pools, wading pools
and
playgrounds.  Take advantage of the summer weather and play outside as
much as possible.  Meet at the nearest park with other families in your
neighbourhood or building and play a pick up soccer game. Schedule
physical
activity time into your daily summer routine.

2.  Your press release mentions that back in the day, “summertime meant we got on our bikes in the
morning
and came back before the streetlights came on.“  How can we
get back to that, especially in large cities?  Is it even possible to
get
back to that type of lifestyle?  Is it as simple as locking the kids
outside?

We can’t
go back to those days nor should it be something to strive
for because our cities and lifestyles have changed. It’s not about
locking our
kids outside but giving kids and parents new sets of keys to so that
it’s
easier for kids and their parents to be active and play outside.

3.  Dr Di Buono mentions that when left to their own devices, kids often
choose sedentary activities like video-games.  You’re a parent – how do
you make sure that unstructured playtime is still physically active?

This is
where parents need to be parents and role models, kids
naturally want to play and it’s more fun with someone – a video game is
often
just a substitute play mate.  Summer is the perfect time to be outside
and
if kids are given an open space with a ball or a Frisbee and or friends -
they
will actively play, run, skip,  and jump.

4.  There is a movement trying to legalize street hockey in the GTA
(yes,
it’s technically illegal).  This seems to suggest that it’s not just
parents that need to take action – it’s the entire community.  What can
individual people do to advocate more effectively for physically active
communities?

We
totally agree with the “takes a village to raise a child”
approach and we as parents and citizens need to start speaking up to our
friends, neighbours, city counselors and others about making our
communities
more accessible to be physically active – legalizing street games,
integrating
our trails and bikes paths into our daily commutes, etc. Lead by
example, if
people see others outside playing – they will follow.

5.  Your press release says that the priority for parents is to find
solutions that are affordable, convenient, and safe, as opposed to ones
that
promote physical activity.  What is the solution? (e.g. make everything
more safe/affordable, convince parents of the importance of PA, all of
the
above, etc).

It
really is a bit of all of the above as all are priorities and
barriers that prevent our kids from being active

The emerging theory of why obesity is associated with disease risk suggests that it is not the excess amount of fat that results in problems – but rather, it is the inability of the fat tissue (specifically subcutaneous, or under the skin fat) to expand enough to store all the excess calories being ingested. In other words, if obese and metabolically unhealthy individuals could somehow develop more subcutaneous fat tissue, they could theoretically become healthier.

That’s right – get fatter and yet healthier.

While these notions surely seem like heresy or simply void of logic to many of you reading, a study just published ahead of print in the journal Obesity, beautifully illustrates the theoretical argument I just described.

In the study, 12 overweight or obese and metabolically unhealthy subjects were given a drug (Pioglitazone) for a duration of 12 weeks. While the exact actions of this drug, and more generally the thiazolidinediones (TZD) class of drugs are beyond the scope of this post, it is important to understand that these drugs seem to upregulate the production of healthy new fat cells (a process known as adipogenesis) – that is they make you fatter. By doing so, these drugs increase the storage capacity of your fat tissue – something that is limited in unhealthy obese individuals.

And that is precisely what happened in these subjects following 3 months of Pioglitizone administration. First, they gained about 2kg of body weight. Their amount of subcutaneous fat in the belly went up by about 10% and that in their butt/thigh by about 24%. Interestingly, their amount of dangerous visceral fat decreased by about 11%. (Some suggest that visceral fat really begins to accumulate and potentially lead to metabolic problems when benign subcutaneous fat runs out of storage space. Thus, not surprising to see an increase in storage capacity of subcutaneous fat and yet a reduction in visceral accumulation).

Also, a fat biopsy from the belly of the subjects showed that the increase in fat mass was due to an increase in the number of small and healthy adipocytes (fat cells) which are better able to take up more circulating fat.

Alright, so people with excess fat and metabolic problems took drugs for 12 weeks which apparently made them fatter, and what happened to their insulin sensitivity (a major metabolic marker of diabetes risk)?

Their insulin sensitivity improved by over 28%!

That’s right – they got fatter and yet healthier.

Interestingly, the authors were able to show a close correlation between the relative increase in new subcutaneous fat cells and insulin sensitivity – the more new fat cells a subject developed, the more their insulin sensitivity improved.

Still believe the “fat is bad” mantra? As this study illustrates, matters related to excess fat and health risk are much more nuanced than what many would have you believe.

Peter

McLaughlin, T., Liu, T., Yee, G., Abbasi, F., Lamendola, C., Reaven, G., Tsao, P., Cushman, S., & Sherman, A. (2009). Pioglitazone Increases the Proportion of Small Cells in Human Abdominal Subcutaneous Adipose Tissue Obesity DOI: 10.1038/oby.2009.380

This post was originally published on Obesitypanacea.com on November 16, 2009.

Image by thienzieyung

Most people know that consuming too much fat, and especially saturated fat, is bad for your health.  That’s why there has been a concerted push for several decades to get people to reduce the amount of saturated fat that they consume, and to replace it with complex carbohydrates.  Now unfortunately people often misinterpret that to mean that fat is evil, but carbs are ok. This is problematic since consuming too many simple carbs is also likely to increase the risk of obesity, diabetes, and cardiovascular disease – exactly what we are trying to prevent in the first place.  So this raises the important question – in order to minimize the risk of heart disease, is it better to reduce the intake of saturated fat, or the intake of simple carbs?  An interesting new study in the American Journal of Clinical Nutrition examines this issue and while it doesn’t provide a definitive answer, it suggests that refined carbs are pretty bad indeed.

The new study was performed by Marianne Jakobsen and colleagues at the Aarhus University Hospital in Denmark, and it has a massive sample – 53,644 healthy men and women.  At baseline (from 1993-1997) these individuals completed a detailed questionnaire regarding their diet, physical activity levels, and other health-related variables including smoking status and socio-economic status.  These individuals were then followed until they had a heart attack, died, emmigrated, or until the end of the study in April of 2008 – whichever came first.

Using the diet questionnaires, researchers calculated both the amount of saturated fat and carbohydrate in the diet, as well as the quality of the carbohydrates being consumed.  This was done using the glycemic index, which measures the impact of a given carbohydrate on blood sugar levels.  For example, sugar and white bread are foods with a very high
glycemic index, vegetables like carrots or onions have a very low glycemic index, and foods like raisins and shredded wheat fall somewherein the middle (more details here).  What did they find?

During an average follow-up of 12 years, there were 1943 heart attacks in the study sample.  Simply swapping saturated fat for carbohydrates (e.g. a 5% increase in energy intake from carbs along with a 5% decrease in energy intake from saturated fat) was not associated
with any change in risk of heart attack.  However, swapping saturated fat for carbs with a high glycemic index (e.g. 5% lower calories from saturated fat, and 5% increased calories from high GI carbs) was associated with a 33% increased heart attack risk.  

Now I should mention a few things up front.  There was no intervention here, so people didn’t actually swap saturated fat for carbs for saturated fat – this was all calculated statistically.  That doesn’t mean I would discount these findings, but I think it’s worth mentioning. Also, diet was assessed once, using self-report, so it would be interesting to see if a similar study with a bit closer monitoring shows similar results.  The authors also mention several times of the “nonsignificant inverse association” between low-GI foods and heart attack risk (HR = 0.88, .72-1.07). With 50,000+ people it’s hard to argue that this study was under-powered.  But as I mentioned the measures of diet weren’t ideal, and this is where I think another study
with more direct measurement could be of real use.  

So what’s the take home message? 

Previous studies have suggested quite clearly that consuming too much saturated fat is a bad thing.  But not surprisingly, swapping out that saturated fat for carbs with a high glycemic index isn’t such a great move either – it’s essentially trading one crappy food for another. Frank Hu lays out an excellent prescription in an accompanying editorial. In it, he suggests that excessive intake of refined carbs (and especially sugar-sweetened beverages) represent the “perfect storm” for increasing risk of chronic diseases.   Fortunately, he points out that many dietary strategies can reduce the intake of refined carbs – for example:

…replacing carbohydrates (especially refined grains and sugar) with unsaturated fats and/or healthy sources of protein and exchanging whole grains for refined ones…

And

limiting sugar-sweetened beverage consumption, a major source of dietary [glycemic load] and excess calories, has been associated with lower risk of obesity, type 2 diabetes, and IHD.

Or

A very-low-fat, high-carbohydrate diet (eg, percentage of energy
<20% from fat and >70% from carbohydrates), once typical in traditional Asian populations, has the potential to be cardioprotective if most of the carbohydrates come from minimally processed grains, legumes, and vegetables and if the population is lean and active (and thus has low insulin resistance)…

And finally

a diet with moderately restricted carbohydrate intake but rich in vegetable fat and vegetable protein improves blood lipid profile and is associated with lower risk of IHD in the long term.Benefits of the plant-based, low-carbohydrate diet are likely to stem from higher intake of polyunsaturated fats, fiber, and micronutrients as well as the reduced GL in the
dietary pattern.

So it really comes down to what
many people have been saying all along – aim for a diet high in plants,
low in refined foods and saturated fat, and limit your intake of sugary
beverages.  And if you’re trying to reduce the amount of saturated fat
in your diet, make sure you’re not simply replacing it with refined
carbs.

Travis

Hu FB (2010). Are refined carbohydrates worse than saturated fat? The American journal of clinical nutrition, 91 (6), 1541-2 PMID: 20410095

Jakobsen MU, Dethlefsen C, Joensen AM, Stegger J, Tjønneland A, Schmidt EB, & Overvad K (2010). Intake of carbohydrates compared with intake of saturated fatty acids and risk of myocardial infarction: importance of the glycemic index. The American journal of clinical nutrition, 91 (6), 1764-8 PMID: 20375186

There’s a lot to experience in the life of a child
Lots of energy to expend…
To play
To dream
To concentrate
So much energy…
To try
And try again
To learn
To grow up

Hazelnuts and skimmed milk:

Now that commercial implies several things. First off, it implies that Nutella is a great source of energy, especially for kids. Well it should be a great source of energy – the first ingredient is sugar. In fact, in a 19 gram serving of Nutella, 11 grams are sugar. Of course that energy won’t last very long before an insulin spike kicks in and makes the kids lethargic, so they are likely to need something more substantial if they plan to “discover the world” for more than an hour or so.

Despite all of these things, the makers of Nutella still claim that it can be part of a complete breakfast. How is that possible? The complete breakfast that they suggest includes multigrain bread and juice (which many people would argue is still not an ideal breakfast), but the point is that the breakfast is complete without the Nutella. If there’s anything that I learned from commercials during Saturday morning cartoons, it’s that anything can be part of a complete breakfast! That doesn’t make it healthy food choice.

I’m not going to stop eating Nutella – just like I’ve never completely stopped eating pizza or drinking pop (although moderation is always a good idea). Just don’t let the good folks at Nutella convince you that it’s a healthy option, especially for kids.

Thanks to my awesome cousin Gina O’Leary for suggesting this topic, and to my (equally awesome) girlfriend Daun for stopping me whenever I reach for the Nutella too frequently.

Travis

This article was originally posted on Obesitypanacea.com on April 30, 2009.