me Jen Mam TorMy weight loss has slowed down this week as I’ve ‘only’ lost 0.6kg (1.3lbs) – I’m blaming my female hormones!  I’ve been busy at work, and have also had my sister-in-law to stay with me for a few days – which has been the lovely bit of my week, as we’ve been out hiking together in the Peak District in a bid to increase my weekly step count.

This week has got me thinking about the myths, presumptions and facts around obesity and weight loss.  In Dr Michael Mosley’s book, he quotes a research paper on this very subject.


A ‘myth’ is defined as: “beliefs held to be true despite substantial refuting evidence”.

A ‘presumption’ is defined as: “beliefs held to be true for which convincing evidence does not yet confirm or disprove their truth”.

A ‘fact’ is defined as: “propositions backed by sufficient evidence to consider them empirically proved for practical purposes”.

When looking at scientific research papers, you need to keep a critical head on your shoulders, and ask yourself many questions before accepting or rejecting the conclusions reached:

– Who has funded the research?

– What type of research was carried out? The gold standard is a double-blind,

randomised control trial.

– Were standard protocols followed?

– Is there any bias involved?

– Were conclusions reached from scientific evidence or have they been reached simply because they’re prudent decisions?

And the list could go on and on…

So I thought I’d take you through some of the myths and presumptions raised in the above article (which interestingly has 20 authors, 9 of whom have disclosed that they’ve received some form of benefit from a range of food and drink manufacturers!).


Myth 1 – “Small sustained changes in energy intake or expenditure will produce large, long-term weight changes.

This myth is close to my heart.  I’m always encouraging people to just make small changes that they can build into their daily routine and maintain, as this will then create a cumulative effect of weight change over the long-term.

However, as the research states, “this relies on the half-century-old 3500-kcal rule, which equates a weight alteration of 1lb to a 3500-kcal cumulative deficit or increment.  However, applying the 3500-kcal rule to cases in which small modifications are made for long periods violates the assumptions of the original model, which were derived from short-term experiments.”

As the article goes on to explain, your body changes its energy requirements (the Basal Metabolic Rate or BMR) as your weight decreases.  Both of these things happen concomitantly (together at the same time), so it affects long-term results.

However, there are other health benefits – reduced insulin resistance, improved cardiovascular function, reduced levels of depression to name a few – not just weight loss, that DO improve over the long-term by making small sustainable changes to your daily routine.  So there’s no excuse not to make those changes!

One of my own ideas (we’ll decide if it’s a myth, presumption or fact later!) is that my own metabolism is VERY quick to react to either a reduction in energy intake or an increase in activity and exercise.

Before I started this diet, I got my BMR tested at Huddersfield University.  I’ll be back there at the end of this 8-week diet to have it retested.  I’m going to be very interested in the results… which I’ll share with you when I’ve got them.


Myth 2 – “Setting realistic goals for weight loss is important because otherwise patients will become frustrated and lose less weight.”

Empirical data – that which is based on experiments rather than ideas or theories – shows no consistent negative association between ambitious goals and program completion or weight loss.  Indeed several studies have shown that more ambitious goals are sometimes associated with better weight-loss outcomes.  Furthermore, two studies showed that interventions designed to improve weight-loss outcomes by altering unrealistic goals, resulted in more realistic weight-loss expectations but did not improve outcomes!!


In the past I’ve been set some very ambitious (to my mind!) weight loss goals.  This resulted in having the opposite effect – I gave up trying to lose weight, resented the goals and the person setting them, and put ON weight through lack of activity and increased eating.  For me, it was a powerful lesson in how I’m motivated.  When set a challenge that I perceive as being tough but doable, I’ll go for it with all my energy – and I’ve achieved some amazing stuff over the past few years!  However, when set a challenge that I perceive as being tough and impossible, I give up before I’ve even started.  If I don’t think I’ve got even a remote chance of achieving something, then I don’t give myself the chance to prove me wrong.  An interesting point to ponder on…


Myth 3 – “Large, rapid weight loss is associated with poorer long-term weight loss outcomes, as compared with slow, gradual weight loss.”

In a large summary of randomised controlled trials, it was found that the long-term weight loss was the same whether the weight was lost rapidly or gradually.  The weight regained once in to ‘maintenance’ mode was also similar for both groups.

In the past I’ve been told to “go for it; opt for quick weight loss, get the suffering over and done with fast, then start living again”.  Up until starting the BSD, I’ve resisted this advice.  My argument being that weight loss is about the emotional battle as well as the physical.  I’ve never tried diets per se before, just used and abused food as a coping method for life. I adjusted to how people treated me.  I made changes to my behaviour (withdrawing from social contact, and lying about my food consumption) to cope with my expanding dress size.

But at the age of 41, wearing a size 32, with a BMI of 52, and weighing 23.5st, I’d had enough.  I reached my ‘tipping point’ of desperation and decided I had to change things in my life.

When I started losing weight I had no weight loss goals in mind.  In fact weight loss wasn’t my first (or even second) priority.  My first priority was to learn how to deal (for the first time in my life) with my emotions, rather than just pushing them all down with food.  I started attending Overeaters Anonymous, and in that first year I lost 4.5st by talking about how I felt instead of bingeing.  So that was an average of 1.2lbs / week.  In the second year of my weight loss, helped by working with a Personal Trainer in the gym, I lost a further 5.5st.  That’s an average of 1.5lbs / week.

When I reached 13.5st (a loss of 10st / 63.5kgs) after two years, I started to feel the panic inside me rise.  People were telling me not to lose any more weight; they started to worry that I was becoming obsessed with weight loss.  I was getting a lot of attention (having spent most of my life being ignored), and wasn’t sure how I felt about it all.  Was my self-worth purely based on how slim I was and how good I looked?  My thoughts went back to being a 5-yr old girl, stood in front of the hospital dietitian and believing that I was a good girl if I’d lost weight that week, and a bad girl if I had put on weight.

When you’ve been large all your life, to emerge as a thinner, fitter person is a strange feeling.  People do react to you differently.  The emotional aspects of weight loss are rarely expressed in an honest way.


Presumption 1 – “Regular eating vs skipping of breakfast is protective against obesity”.

Two randomised controlled trials studying this outcome found that it had no effect on weight in the total sample.  However, what was brought out was the difference in baseline breakfast habits.  For example, if you regularly didn’t eat breakfast before the trial, but then were assigned to the group of people who did eat breakfast, you were likely to put on weight as you consumed an extra meal.  The jury still seems to be out on this presumption.


Presumption 2 – “Early childhood is the period in which we learn exercise and eating habits that influence our weight throughout life”.

Although studies show that a person’s BMI typically tracks over time, it’s suggested by longitudinal genetic studies to be down to your genes rather than a persistent effect of early learning.

Genetics and gut bacteria are two topics that were discussed in the recent Horizon programme “Why are we getting so fat?” (which I was featured in) and will be the subject matter of a public meeting in Cambridge on the evening of Mon 20th June.  If you’ve got a ticket, I’ll see you there – come up and say hello.

Certainly for me, I learnt at a very young age that food made me feel better, and all activity left me hot, sweaty and uncomfortable.  The fact I was always last to be picked in the team during PE lessons did little to improve my love of activity!


A major glitch with myths and presumptions regarding obesity is that they focus on one particular aspect of weight loss in isolation.  Life is not like that.  Obesity needs to be tackled as part of a holistic, multifaceted program.


So… that’s Week 3 done and dusted.  My experiment with the 8-wk Blood Sugar Diet now moves into its fourth week.  Will my weight loss pick up again?  Will my body further adjust to the lack of food?  Or will the continued increase in physical activity create more weight loss and other health benefits too?

Catch you next week.