Across the
globe, millions of people will commit themselves to a New Year resolution to
lose weight. Almost all will fail. The 5-year cure rate for obesity is less
than the 5-year cure rate for the worst cancer, a view articulated by the
American Medical Association’s Council on Scientific Affairs almost 25 years
ago. If dieting were a drug, it would have failed the regulatory process given
that it is generally not a long-term success. Yes, there are successes but they
require life long adherence to a restricted food intake. Basically speaking, when we gain weight
and retain that gain for some time, it is recognised biologically as a new
norm. When we lose weight, that same norm is constantly there and constantly
wishing to re-establish itself. Losing weight is easy. It’s retaining that
weight loss which is huge challenge. Rule number one in weight management:
Whatever your weight is now, don’t gain any more. That is a battle you can
win.
There is a
second battle you can win and that is to get fit and in so doing, you will
negate all of the adverse effects of overweight and obesity. There is a wealth of literature to show
that it is better to be fit and fat than slim and sedentary. Physical activity
will restore blood pressure to normal and will restore the ability of the body
to handle glucose thereby reducing the likelihood of obesity-related diabetes.
Physical activity enhances a sense of wellbeing, something that is readily lost
when people gain weight. One of the very best teaching aids on the health benefits
of physical activity is available at http://www.youtube.com/watch?v=aUaInS6HIGo.
Obesity and
overweight remain among the major challenges to public health nutrition that we
face today. The food industry and particularly the fast food industry are the
focus of attention. And whilst food intake must be a part of the solution, so
too must physical activity. The problem is that we have constructed a way of
life that is sedentary and we have designed a built environment to support
that. One of the most inspiring exponents of physical activity is Professor
James Levine from the Mayo Clinic. He has championed the concept of NEAT: Non
Exercise Activity Thermogenesis. Basically, most of the energy we consume
is dissipated as basal energy needs for the functioning of our heart, lungs,
kidneys, brains and son on. We also dispose of some energy in digesting and
absorbing food but this is minor. After basal activity comes exercise activity
thermogenesis. This area of energy expenditure is planned as a walk, a game of
golf, a jog, a swim and so forth. Levine has defined another activity (NEAT), which
is effectively “fidgeting” or physical activity that is not seen as intentional
physical activity: picking up the phone, walking to the bathroom, standing up
to give a presentation. So, lying down at complete rest costs 5.4 kilojoules
(Kj) per minute. That goes up to 5.6 if seated at complete rest. Sitting but
“fidgeting” raises the figure to 8.2. Now lets take a look at the same
activities while standing. Standing motionless has a cost of 6.1Kj. Standing but fidgeting now increases
the value to 10.3. Walking in a stop start fashion as in many work places
raises the value to 13.7. Thus simple acts of physical activity make a huge
difference to energy expenditure. Levine published a scientific paper in the
very prestigious journal Science in which he overfed volunteers with an
additional 1000 calories per day. Before the study and during the study, ALL
volitional activities were controlled and minimized. He used advanced
techniques to measure body fat (DEXA scans) and energy expenditure (stable
isotopes). Having overfed these people for 8 weeks with an additional 1000
calories, all subjects gained weight. However, as I’ve explained before Blog of
November 14th last) , genetic variation will mean that some people
will gain more weight than others. But in what fraction of energy expenditure
was between-subject variation related to gain in fat mass? Not basal metabolic
rate and not the thermogenesis of eating. There was a powerful negative
correlation between NEAT and fat gain. The more fidgety the person, the lower
the weight gain. Levine has gone on to design a unique office, which
facilitates NEAT. The telephone is as far from the desk as possible. The desk
can be elevated to facilitate standing and he has also designed an award-winning
desk[1],
which has a two-mile an hour treadmill option to facilitate NEAT (http://store.steelcase.com/products/walkstation/).
We have as much
obligation to tackle our obesogenic built environment, as we have to tackle our
food intake. However, architects and ergonomic designers of comfortable offices
are not as attractive a villain as is the corporate food sector.
No comments:
Post a Comment
Note: Only a member of this blog may post a comment.