Nutrition Myth #7 - Starvation Mode

At some point in our attempt to lose weight, especially after seeing a noticeable drop, we reach a plateau.   The numbers just seem to stop going down.

A quick Google search and we discover that our body has entered “starvation mode”.

Starvation mode is often described as a condition where our body not only refuses to lose any more weight, but it will begin to store calories in an attempt to prevent starvation.

We also hear stories of people being unable to lose any additional weight until they actually start eating more calories to “trick” their body into believing they are no longer starving.

 

There are many theories as to why weight loss plateaus occur after a period of dieting.  One popular theory is the "set point" theory. This theory suggests biological control of body weight is regulated by feedback loops from peripheral organs and tissue, such as leptin secretion from adipose tissue, back to the central nervous system to rebalance and maintain homeostasis.  Another theory is a "settling point," which reflects metabolic adaptations to energy imbalance without specific feedback control. (1)

Unfortunately, these are theories with very little evidence behind them.   The main reason people tend to plateau is that we stop being as diligent in our diet; we get comfortable, complacent, we stop tracking the calories so avidly (so we believe we are still eating less, even though we forgot to add that extra snack or drink) or one ‘cheat day’ becomes two.

That and people invariable underestimate how many calories they have consumed (2)

Failing to adhere to a diet, not metabolic adaptation, is a major contributor to the weight-loss plateau and weight regain (3).

 

Adaptive Thermogenesis

This is the pseudoscience that we hear about regarding your metabolism changing in response to diet, exercise and weight loss.  Other adaptations may take place and may affect your BMR over time, but Adaptive Thermogenesis is now thought to be a concept, rather than an actual thing that can be quantified. (4)

Slowing of metabolism can be substantial and persistent and plays a part in halting weight loss and putting subsequent weight regain into motion. (5)

However, the typical weight regain is usually driven by failing to adhere to a diet, exponentially over time.   We just get bored or complacent along with difficulties in sustaining changes to dietary choices and behaviours that affect our ability to enjoy, celebrate, and socialise with food. (6)

 

But, what if this is not you?  What if you are still being super diligent and you are plateauing?   This is still normal.   But you absolutely are not in starvation mode.

 

Basal Metabolic Rate (BMR)

BMR is the number of calories you would burn if you simply laid in bed all day and did nothing and this alone accounts for the majority (around 65%-75%) of the total calories burned throughout the day.

Also, the larger you are, the more calories it takes to keep you alive.  More calories are required to walk and much more are required to climb stairs so as you lose weight you require fewer calories to keep you going.  

For a typical 16st / 100kg man in their 40’s their BMR may will be around 2,000 calories a day (7-9).  If you reduce your calories to 1,700cal a day – an 15% deficit you will begin to lose significant weight.

Now let’s say, over 6 months you hit 12st / 76kg, your BMR will have dropped to around 1,700 cal.   You are still on your diet and consuming 1,700 calories but now there is no calorie deficit, you are now eating to maintain your BMR.   No wonder you are not losing any more weight.  You no longer require as many calories to survive.

 

Non-Exercise-Activity-Thermogenesis (NEAT)

Let’s say you did actually get out of bed and do something.   Non-Exercise Activity Thermogenesis is the additional energy required to just do stuff; walking, cooking, cleaning, driving, shopping.   All of the activities which we don’t consider as ‘exercise’.   Your NEAT will vary depending on your lifestyle.    Someone with a physical job, or a stay-at-home mum with young children, will have a higher NEAT than someone who is deskbound.

If your lifestyle changes and you become more sedentary, while you may still be going to the gym five times a week, this could account or a reduction in weight loss.   You are no longer burning as much energy.

 

Thermic Effect of Activity (TEA)

The thermic effect of activity (TEA) is usually what people think of when they talk about burning calories. This is the number of calories that you burn from intentional exercise.

Depending on how active you are, this can represent anywhere from 0%-20% of your total daily energy expenditure.

But you now weigh less.   That 5k run you were doing in 30 mins when you were 16st was burning around 420 cal (10), now you are a 12st racing snake you are only burning around 350 cal. Now you weigh less, it is easier to run so your exercise is not burning as many calories. You now need to up your game.

Summary

The most common reason for plateauing is a deviation from a diligent diet over time, but even if you are being diligent, now you weigh less, you require less so the only weight to keep on losing weight is to eat even less and / or work harder.

But you know what?   Even if you don’t, you have still lost all of that weight and if you continue with your current eating and exercise regime, you will remain at that weight for as long as you want.

Just don’t give up.   That is when we regain.

 

References

  1. Müller MJ, Geisler C, Heymsfield SB, Bosy-Westphal A.  (2018)  “Recent advances in understanding body weight homeostasis in humans”. F1000 Research, Faculty Review.

  2. Dulloo AG, Jacquet J, Montani JP, Schutz Y.  (2012)  “Adaptive thermogenesis in human body weight regulation: more of a concept than a measurable entity?”  Obesity Review.  13 Suppl 2:105-21.

  3. Freedoff Y.  Hall KD.  (2016)  “Weight loss diet studies: we need help not hype”.  The Lancet.  388(10047)849-851

  4. Dulloo AG, Jacquet J, Montani JP, Schutz Y. (2012) “Adaptive thermogenesis in human body weight regulation: more of a concept than a measurable entity?” Obesity Review. Dec;13 Suppl 2:105-21.

  5. Thomas DM.  Martin CK.  Redman LM.  Heymsfield SB.  Lettieri S.  Levine JA.  Bouchard C.  Schoeller DA.  (2014)  “Effect of dietary adherence on the body weight plateau: a mathematical model incorporating intermittent compliance with energy intake prescription”.  The American Journal of Clinical Nutrition.  100(3):787–795

  6. Polidori, D., Sanghvi, A., Seeley, R.J. and Hall, K.D. (2016)  “How Strongly Does Appetite Counter Weight Loss? Quantification of the Feedback Control of Human Energy Intake”.  Obesity. 24: 2289-2295.

  7. https://www.diabetes.co.uk/bmr-calculator.html

  8. https://www.active.com/fitness/calculators/bmr

  9. https://www.calculator.net/bmr-calculator.htm

  10. https://keisan.casio.com/exec/system/1350959101