How our biology scuppers our weight loss

I’ve just spent the last three days at an eating disorder conference.  Partly for professional development but mostly because we’re now almost in September and I’m no leaner than I was when I set about losing weight in January.  I want answers damn it!  Not the obvious ones like, you must still be eating too much.  But the reasons behind why this is true for me.  Or more precisely, why it’s still true for me despite four serious attempts at shifting the weight over the past eight months.  I got at least some of those answers but it was pretty challenging stuff.  The science behind all this is brutal.

One of the presentations was from an eminent obesity researcher.  He opened his lecture by saying that if he was only interested in his clients losing weight (as opposed to studying them) then he’d close his clinic and send them all off for weight loss surgery as this is the only effective way to lose and keep off significant amounts of weight.  Huh?  Seriously?  We’ve got to be cut open and have our stomachs partitioned in order to lose weight?  This isn’t what I was expecting to hear.

He went on to explain the science behind the statistic that most of us have heard:  95% of us regain any lost weight within five years.  Unless you’ve had weight loss surgery.  In this case you may look a little like a melted candle as the weight came off too quickly but you’re much more likely to still be fitting into your new skinny jeans.

It turns out that our weight is mostly genetically determined.  We know this partly because identical twins raised apart weigh the same as each other rather than their adoptive parents.  And partly because, apparently, you can isolate and overfeed people in exactly the same manner and only some of them will gain weight.  It seem our bodies achieve this through regulating appetite and energy expenditure.  What’s really interesting in terms of weight loss is that the body uses these same mechanisms to reclaim weight lost.

In my case there is no clear genetic predisposition to being overweight as neither of my biological parents have this issue.  I can only really blame an attractive combination of emotional eating, greed and laziness.  So biology wasn’t destiny at the start.   However, where it now trips me up is that once I created a new ‘set point’ by gaining weight, my body wants to defend that weight gain.  All very useful back in the days where food wasn’t plentiful and my fat reserves may have enabled me to survive while all those skinny minnies around me perished.  But a right pain in the neck in a world of supersize snacks and 24 hour convenience stores.

When we lose weight our bodies do two things to encourage us to regain it:

• Firstly it turns down our energy burning thermostat and conserves about 300 calories a day.  This means that I may now weigh  the same as my best friend but if her weight has never deviated she can eat two chocolate biscuits and a skinny cappuccino more than me each day and still maintain her weight.  Bitch 🙂
• So one important way to maintain weight loss is turn consciously and consistently burn up that 300 calories through walking 10,000 steps or whatever activity works for you.  If we don’t compensate for the energy conservation then we’ll start to regain.
• The second cruel and unusual tactic our body uses to encourage us to regain is to regulate the hormones that control our appetite and satiety cues.  The body pumps up ghrelin to make us hungrier and then turns down other hormones that tell us when we’re full.  Sneaky.
• The real kicker is that the body will maintain these changes, to energy expenditure and appetite, until we’ve regained the weight.  Which means we need to be in a continually defensive position to over-ride these processes.

Again, this doesn’t fit entirely for me.  In the past I’ve lost significant amounts of weight twice and kept it off for four years both times.  No, I didn’t make it past the magical five years but the regain wasn’t the gradual type that would be indicative of these biological processes triumphing.  Instead it was the result of a return to emotional eating in the face of major life stressors:  Firstly when I returned to university and later when I had a child.  Not situations I dealt with gracefully!  But it does help to explain how nearly all of the 8 kilos I lost earlier this year through intermittent fasting found their way home.

I was pretty depressed when first faced with all the charts and graphs showing how our biology tries to be our weight loss destiny.  But ultimately the take home message for me wasn’t about the necessity for weight loss surgery (no thanks) but that we need to be continually aware to over-ride these processes.  I don’t have all the answers but moving more every day, restricting refined carbs  and eating more good fats would be a start.  More about this to follow.