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Debunking Calories In vs Calories Out for Weight Loss: Assumption #1

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When any government organisation or weight-loss guru advocate eating less and exercising more to lose weight, they are really trying to bend and contort the Calories In vs Calories Out principle into a weight loss strategy.

To apply this principle to weight loss they are forced to make some assumptions.

Assumption #1

That the only two variables that impact our body fat stores are the calories we consume and the calories we expend.


The calories we consume and the calories we expend are not the only determinants of what gets stashed away in our fat stores.  Anyone who ponders this for long enough will realise that they actually knew this all along.

The 10 other factors that can also influence our fat mass

1. Our genetics:


Image by ynse from Poland, via Wikimedia Commons

The age old argument of nature vs nurture.
Does body weight and a tendency towards being overweight run in families because of genetic inheritance?
Or, is it due to the probability that people living in the same household would be eating the same foods and be exposed to the same environmental factors and toxins?
We are probably all aware that it is some kind of mixture of both.
But going one step beyond that, epigenetic research suggests that nature and nurture could be inextricably intertwined because of the effects they have on each other.
In Deep Nutrition,authors Cate and Luke Shanahan explain that our genetic heritage is not static.  Our environment (including our eating habits) can affect how our genes are expressed and how this is passed on to our children.

Epigenetic researchers study how our own genes react to our behaviour, and they’ve found that just about everything we eat, think, breathe, or do can, directly or indirectly, trickle down to touch the gene and affect its performance in some way.  These effects are carried forward into the next generation where they can be magnified.” – Cate & Luke Shanahan, Deep Nutrition

Consider these examples from Deep Nutrition:

  • Foetal alcohol syndrome, resulting from a mothers alcohol consumption during her first trimester of pregnancy.
  • In the Dutch winter famine towards the end of WWII, over 30,000 people starved to death.  The malnourished survivors gave birth to children who were smaller than average and more susceptible to obesity, diabetes, heart disease and cancers.  Not only that, those children grew up and gave birth to children who were also smaller than average at birth.
  • The development of different diseases and dysfunctions in identical twins and then their offspring.
  • The increased incidence of asthma in children born to mothers who continued to smoke throughout their pregnancy vs non-smoking mothers. Even more amazing is the increased incidence of asthma in children whose grandmothers were smokers while pregnant, even if their mother had never been a smoker!

…different life experiences can lead to different genetic function…in fact, every bite you eat changes your genes a little bit.” – Cate & Luke Shanahan, Deep Nutrition

So, not only is it a case of “we are what we eat”, we are also what our parents ate and what our grandparents ate!


2. Hormonal signalling and the sensitivity of different tissues to hormones like insulin, leptin, cortisol, estrogen and dopamine:

One simple example of this is to think about how differently fat mass is stored and lost in males vs females.
In the ladies, excess fat tends to be stored in the chest, bum and thighs and for men it is the gut.  These differences are partly due to differing levels of sex hormones including estrogen and testosterone.

Another example of how hormones affect fat mass is when genetic mutations, lesions or tumors in the hypothalamus interfere with the brains sensitivity to leptin signalling. [The hypothalamus in the brain is responsible for regulating sleeping, eating and thirst...among other things.]
People and animals that are afflicted with genetic mutations, lesions or tumors in this area become seriously obese and extremely lethargic.
Even in the face of severe caloric restriction, patients eating only 500 calories a day were still shown to steadily gain weight.
Robert Lustig, MD & paediatric endocrinologist, talks about his research in this area with Sean Croxton on Underground Wellness Radio.


3. Our metabolic rate:

As determined by thyroid function.


4. Sleep deprivation:

Is stressful on our bodies. See this previous post on why getting enough, quality sleep is so important to weight loss efforts.


5. Stress levels:

American biologist and author Robert Sapolsky.

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Eating too much can be stressful, eating too little can be stressful, infections are stressful, overtraining can be stressful.
Mental, emotional and physical stress can all contribute to dysregulated cortisol levels and set off a hormonal cascade that ends in raised insulin levels, insulin resistance and the hoarding of body fat.

Robert Sapolsky also refers to the Dutch Hunger Winter of WWII, in his book Why Zebras Don’t Get Ulcers.  Starvation is stressful to both a pregnant mother and her foetus.
The information that the stressed foetus gets from its starving, malnourished mother, is that food supply in the outside world sucks, so it had better store whatever calories it can, when it can.
These Dutch WWII children had a lifelong super ability to store calories, resulting in higher than average rates of obesity and other chronic diseases.

Also, take a look at this previous post on how the stress associated with sleep deprivation affects our fat mass.


6. Different medications:

Some antidepressants, antipsychotics, glucocorticosteroids, oral contraceptives and diabetes medication can influence fat mass and are associated with weight gain


7. Food toxins:

Otherwise thought of as NAD’s (neolithic agents of disease) by Dr Kurt Harris.
These include:

  • Excess fructose
  • Excess polyunsaturated omega-6 fats (particularly in the form of vegetable oils), and
  • Cereal grains especially when refined and made into products like bread and pasta.

These food toxins can irritate the gut and cause the gut lining to become more permeable (also known as leaky gut syndrome).
This increases systemic inflammation, as particles and pathogens gain unauthorized access to the body and stimulate an immune response.
At the end of the line, this will disrupt hormonal signalling and sensitivity.

One of the most interesting hypotheses is that increased intestinal permeability allows inflammatory substances to cross into the circulation from the gut, irritating a number of tissues including the hypothalamus” – Stephan Guyenet, Neuroscientist and blogger at Whole Health Source

Inflammation of the hypothalamus is proposed to reduce leptin sensitivity and blunt signals from the body that ‘there is enough fat in the storage, so no need to eat any more right now.’


8. Food sensitivities:

Allergies & autoimmune responses will increase underlying systemic inflammation.  There is also an association between increased gut permeability and allergic & autoimmune diseases contributing to further inflammation and hormonal disruption.


9. Environmental pathogens and our gut flora:

Pathogenic invasions and the overgrowth of certain bacteria, fungi, yeasts, viruses, protozoans and other microbes in our guts can affect our fat mass.  Paul Jaminet has noted that some adenoviruses have been associated with obesity in animals and humans.
On Chris Kresser’s first Healthy Skeptic Podcast, Stephan Guyenet also talked about the effect of gut flora on fat mass.  He referenced studies in mice showing that obesity can be transferred between animals by transferring their gut flora.


10. Malnutrition:

Particularly micronutrient deficiencies but also some macronutrient restrictions can cause us issues.
Deficiencies in choline and vitamin D have been linked to inflammation, insulin insensitivity and obesity.  Consider also the example given above of the descendants of those malnourished survivors of the Dutch Hunger Winter of WWII.


Take home messages:

  • Our fat mass is controlled by more than just calories in vs calories out.
  • We need to take into account all of the other contributing factors such as genetics, hormones, sleep deprivation, gut flora, stress levels, our metabolic rate, food toxins, systemic inflammation, environmental pathogens and the type of food we are consuming.
  • Many of these 10 factors are linked: both stress and a lack of sleep affect hormonal signalling & sensitivity which affects our appetite, our motivation to go find more food and also our motivation to move, exercise and play.  Food toxins, pathogens, micronutrient deficiencies and gut permeability can all increase our levels of systemic inflammation which will disrupt our hormones.
  • The issues underlying all of these factors are: disrupted hormonal regulation and increased systemic inflammation in the body. Fix these and you will fix problems with body fat regulation.
  • What you eat today affects not only your own health but also the health of your future children and grandchildren


“Help! I want to make a change, what can I do today?”

  • Make getting good quality sleep a priority.  Go to bed earlier, reduce artificial light exposure after sunset and sleep in a pitch-black room.
  • Take a critical look at your stress levels, minimise the things (or people) that cause you the most stress. Consider meditation and other relaxation strategies to help you cope with the things you are unable to change.
  • Find any vegetable oil in your house and throw it out, use olive oil, coconut oil, butter, and ghee instead.
  • Cut out processed foods, focus on eating whole foods and prepare more of your meals at home.
  • Take a look at the nutrient value of your diet and consider if you need to supplement with the likes of fish oil, vitamin D or a multivitamin.
  • Consider a 30-day elimination of food toxins to kick start the healing and recovery of your body. This will increase your gut health and immunity, reduce your inflammation and potentially identify any food sensitivities. Check out the Whole30 for some guidelines on how to go about doing this.
  • Be more mindful of the effect that your diet, sleep habits and stress all have on your body. There are times when I have been unaware I was stressed out till my eczema flared up and face broke out with acne. You might find it helpful to keep a food and mood diary.


So, do you think you will do anything differently now?
Were any of these factors surprising to you?  Have you tweaked your lifestyle with any of these and seen good results with fat loss?
Tell us what you think in the comments below.


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