Is Your Waist Circumference Sabotaging Your Immune System?

This week I’m talking about something called Central Adiposity, or the more fancy term being “Belly Fat”.

Why is this important?  

Well, just like high blood pressure, obesity has an inflammatory component which means it can interfere with the immune response and vice versa.

In a review published in the Proceedings of the Nutrition Society (2012), researchers stated:

Obesity, like other states of malnutrition, is known to impair the immune function, altering leukocyte counts as well as cell-mediated immune responses. In addition, evidence has arisen that an altered immune function contributes to the pathogenesis of obesity. 

When we’re carrying extra weight, especially around the middle, it shifts our biology out of balance because fat cells release pro-inflammatory proteins called cytokines.

In other words, fat cells are a living breathing thing. They’re not stagnant that just sit there and do nothing!

They’re actually endocrine cells because of their ability to secrete hormones and influence cells in other parts of the body, that in many cases, can lead to further weight gain.

Sorry, not exactly the rosiest of scenarios but it’s important that I tell it as it is!

Now one hormone in particular, insulin, is the biggest contributor to belly fat. 

Insulin is produced by the pancreas to help move sugar out of the bloodstream and into the cells so that it can be used for energy, or stored in the liver and muscles in the form of glycogen for later use.  

However, what most people don’t realise is that when the body is experiencing high levels of insulin due to various lifestyle, nutritional and environmental factors – it leads to belly fat because insulin is a fat-storage hormone.  

So when the body is having to produce endless amounts of insulin (especially in the case of insulin resistance), as it tries to remove it from the blood vessels, excess glucose gets stored around the belly or torso area. This is the body’s basic evolutionary instinct to help us to survive the winter when food is scarce.  

Thankfully we don’t live in a world of food scarcity (in fact the complete opposite – we have access to food 24/7!), so over time, this can cause us to develop a shape similar to that of an apple :-).

Or others refer to it as having more of a spare-tyre-type-physique that seems to want to hang on for dear life! Perhaps you can relate.

So What Are The Categories of Abdominal Obesity?

According to the Harvard School of Public Health, it varies, depending on sex:

In women, it’s a waist circumference greater than 88cm or 35 inches
In men, it’s greater than 102cm or 40 inches.

What Can We Do To Prevent or Reverse Belly Fat?

The main goal, or focus, needs to be on reducing insulin levels because remember insulin is a fat-storage hormone, which means fat-burning will not occur, until we get our insulin levels down low.

Elevated insulin levels also increase hunger and therefore food intake, so we need to work on reducing food cravings by balancing blood sugar levels.  Some suggestions include the following;


  • Cut Back on the Sugar – OK, so I’m not going to be too popular for this, but cutting back on sugar intake is hands down the most important aspect of reducing blood sugar and insulin spikes. So if there’s a drawer in your workplace that is stashed with lollies (I know there is one somewhere as all workplaces have them!) – please step away from that drawer.  Instead follow the tips below to help to curb sugar cravings in the first place and of course, be mindful of grazing on those lollies mindlessly just because they’re sitting in front of you.

    From an immune perspective sugar also feeds the bad bacteria in the gut making them thrive, which can lead to an imbalance in the delicate balance of the gut microbiome – home to 70% of the immune system.  
  • Include Protein in Every Meal – protein helps to curb sugar cravings by producing less of the hunger-stimulating hormone ghrelin, and more PPY, a hormone that signals fullness.  This will lead to less snacking, reducing blood sugar and insulin spikes.

    Examples of protein include plain Greek yoghurt, eggs, nuts, cottage cheese, broccoli, beef, chicken and lentils.
  • Increase Intake of Soluble Fibre – soluble fibre is a type of fibre that absorbs water and forms a gel, which slows down the movement of food through the digestive tract.  Like protein, this helps to keep you feeling fuller for longer, as well as keeping blood sugar and insulin from rising too quickly after eating.

    Soluble fibre can be found in foods like flaxseeds, avocados, legumes, pears, carrots, figs and apples.
  • Minimise Food Intake During the Night – In a study published in the Proceedings of the Nutrition Society (2019), subjects who worked either night shift or rotating shifts, and had abdominal obesity, were asked to rearrange their meal and snack times to create a five hourly night fast between 1am and 6am.  After 4-weeks, both body weight and body mass index (BMI) were significantly lower illustrating how by simply changing when you eat, can be an effective weight-loss strategy. 


  • Create a Bedroom Sanctuary – not getting enough sleep drives sugar and carb cravings by affecting appetite-regulating hormones so we need to do whatever we can do improve both the quality and quantity of sleep! One simple way is to make your bedroom a place that you want to sleep. So if it’s filled with clutter or your bed is uncomfortable because it’s over 10-years old – then perhaps it’s time for a bedroom overhaul.

    So go out and buy the expensive sheets and the fluffiest of pillows because we spend one-third of our lives sleeping (maybe not quite as much when we work 24/7!) – which is why creating a bedroom sanctuary can be one of the best financial investments in your health.


  • Reduce Stress in Your Life – now I know this can often be easier said than done, but chronic stress increases the production of the stress hormone cortisol which promotes the accumulation of belly fat.  So finding ways to offload things in your life that are not serving you, and incorporating more stress-reducing strategies into your lifestyle such as going for a walk in nature, meditating, taking up a hobby like painting or playing an instrument can be great ways to start to reduce stress in your life.  In other words, do whatever brings you joy and reduces feelings of stress!
  • Get Serious About Your Alcohol Intake – an occasional glass of wine or beer is not going to be the end of the world, but if it’s a daily habit it can become very problematic. Try taking a few weeks off and see how you feel.  Then if you feel like it, gradually bring it back in but maybe 1 or 2 times a week.

So there you go!  Lots of different ways to help keep your waistline in check, along with contributing to a stronger and more robust immune system.

Audra x

P.S:  If you want to learn more about reducing weight whilst working 24/7, I cover this in Chapter 2 of my book Too Tired To Cook– which is titled ‘My Uniform Must Be Shrinking – Weight Fluctuations and an Expanding Waistline!’  Click Here to check out some of the reviews on Amazon, or purchase it for yourself or a friend!



Bonham, M, Leung, G, Davis, R, Sletten, T, Murgia, C, Young, M, Eikelis, N, Lambert, E & Huggins, C 2017, ‘Does modifying the timing of meal intake improve cardiovascular risk factors? Protocol of an Australian pilot intervention in night shift workers with abdominal obesity’, British Medical Journal, vol. 8, no.3, pp. 1-9.

Coelho, M, Oliveira, T & Fernandes, R 2013 ‘Biochemistry of adipose tissue:  an endocrine organ’, Archives of Medical Science, vol. 9, no. 2, pp. 191-200.

Leung, G, Davis, R, Huggins, E, Rosbotham, Warnock R & Bonham, M 2020 ‘Rearranging meal times during night shift work promotes weight change:  a randomised crossover intervention in shift workers’, Proceedings of the Nutrition Society, vol. 79.

Perez de Heredia, F, Gomez-Martinez, S & Marcos, A ‘Obesity, inflammation and the immune system’, Proceedings of the Nutrition Society, vol. 71, no 2, pp. 332-338.

Rodin, J 1985, ‘Insulin levels, hunger, and food intake: An example of feedback loops in body weight regulation, Health Psychology, vol. 4, no. 1, pp. 1-24.

Volek, J, Phinney, S, Forsythe, C, Quann, E, Wood, R, Puglisi, M, Kraemer, W, Bibus, D, Fernandez, M & Feinman, R 2009, ‘Carbohydrate restriction has a more favourable impact on the metabolic syndrome than a low fat diet’, Lipids, vol. 44, no. 4, pp. 297-309.


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