Updated: Feb 21
Losing weight isn’t just about calories in versus calories out.
Research shows that inflammation is one of the main drivers of weight gain and obesity. It can prevent fat loss regardless of what type of diet and exercise plan you follow - and the importance of managing inflammation is often over-looked in many diet plans. A recent review of food trends published in Current Treatment Options in Gastroenterology found that processed foods are linked to inflammation and obesity. Diet plans that include packaged meals or shakes; or plans that advise “everything in moderation” normalise the use of processed foods and can actually be perpetuating the problem and preventing weight loss.
Inflammation is the way in which our immune system protects us from bacteria, viruses and toxins. It can also help neutralise other foreign substances such as certain food molecules, medications, toxins and environmental pollutants. It is therefore a necessary protective mechanism. However, when the immune system is over-activated by excessive exposure to various substances, it can damage normal cells and change the function of key organs including those involved in weight loss.
Here’s how inflammation affects these key organs and leads to weight gain, and what you can do to reverse it.
The gut microbiota and inflammation.
The gut microbiota plays a large role in regulating our immune system and metabolism. It digests dietary fibres and converts them into molecules called short-chain fatty acids. These fatty acids help maintain a healthy gut wall, activate a healthy immune response within the gut wall and have many other benefits throughout the body. More information here
In a healthy gut, the microbiota maintains a state of immune tolerance. Fatty acids activate immune cells just enough for them to rapidly deal with any antigens or foreign substances that enter the gut without causing local damage or systemic inflammation.
Certain foods, medications, toxins and stress can reduce the number of healthy bacteria and increase the number of bad bacteria (this is known as dysbiosis). Dysbiosis can damage the gut wall, making it more permeable to foreign substances (this is known as leaky gut). Antigens can then pass through the gut wall and enter the blood stream where they trigger an immune response. This can lead to systemic inflammation and produce widespread effects. In addition, when bacteria such as E.coli increase in numbers they release a large amount of a molecule called endotoxin (also known as lipopolysaccharide). Endotoxin has been found to stimulate a potent inflammatory response both in the gut and in various organs throughout the body. More information here.
There have been a large amount of studies showing that endotoxin in the blood stream (termed endotoxemia) is associated with a range of inflammatory states such as:
An increase in the inflammatory marker, c-reactive protein (CRP)
Higher body mass index (BMI)
Adipose tissue inflammation
Inflammation within the liver
Neuroinflammation (inflammation within the brain)
It is important to note that sugar and saturated fats can also initiate inflammation in various organs. These food constituents are routinely added to many processed foods – including some that are marketed as weight loss products.
If you follow the standard dietary recommendations or regularly consume packaged foods, it is possible that you have some degree of chronic inflammation in the body. Inflammation in the gut can lead to food intolerances and allergies. When inflammation involves organs that are responsible for regulating food intake and maintaining metabolism, it can lead to symptoms such as cravings, increased appetite, anxiety, depression, insomnia, brain fog, fluid retention and fatigue. It can also cause weight gain and resistance to weight loss.
Niccolai et al. Nutrients 2019, 11(1), 156; https://doi.org/10.3390/nu11010156
Inflammation within fat cells
Studies show that dysbiosis and endotoxemia are associated with inflammation in fat cells which causes them to function differently from normal fat cells.
Firstly, they produce much more leptin – which may seem beneficial because leptin is a hormone that tells the brain when you are full – so it reduces hunger. However, when there is too much leptin – as is the case in inflammation - the brain stops responding to it. This is known as leptin resistance and it means there’s no “off” switch when it comes to food, so you continue to eat beyond what your body needs.
Secondly, inflammation in fat cells has been associated with insulin resistance. Insulin is the hormone that enables our liver and muscle cells to use and store glucose for energy. When these organs become resistant to insulin, they no longer utilise glucose and this results in excess glucose in the blood stream which then becomes stored as fat. In addition, insulin sends signals to the brain to reduce hunger. People with insulin resistance don’t detect these signals and tend to feel hungry most of the time. They also gain weight quickly - and out of proportion to calorie intake - particularly when they eat carbs as the body is no longer managing them efficiently.
And finally, inflamed fat cells produce more inflammatory cytokines and immune cells that exacerbate and perpetuate the problem.
Inflammation in the liver
The liver is the organ responsible for detoxification and it also plays a role in the metabolism of fats and glucose. When the liver becomes inflamed – these processes are impaired.
A build-up of toxins within the body can disrupt a range of hormones such as insulin, leptin, estrogen and thyroid hormones – all of which are essential for maintaining a healthy weight.
Also, when glucose and fat metabolism become dysregulated, it ultimately leads to fatty liver and weight gain.
Inflammation in the Brain
Inflammation in the brain, (termed neuroinflammation), can affect a number of brain functions that are involved with weight management.
Mice studies have found that diets high in saturated fats can produce inflammatory changes in the brain within several hours of meal consumption. In humans, one study found that those with a higher BMI have increased activation of inflammatory cells in the brain.
Depending on the site of inflammation a number of processes can be impaired.
Inflammation within the hypothalamus, (a region of the brain involved in appetite control and weight homeostasis), reduces our ability to detect signals of fullness, resulting in increased hunger and over-eating.
The hypothalamus also regulates the stress response so inflammation in this region can increase the production of the stress hormone, cortisol. Cortisol has been shown to trigger an enzyme that increases fat storage, particularly around the abdomen, thighs and upper arms. Cortisol also contributes to both insulin and leptin resistance, and it dysregulates the immune system resulting in a self-perpetuating cycle of inflammation, cravings, over-eating, weight gain and more stress.
The corticolimbic system includes areas of the brain that are involved in cognitive function, learning, emotional control and the stress response (to name a few). When these areas are affected by inflammation, our ability to make decisions becomes impaired, we also find it hard to manage stress and to resist food cravings.
In addition, neuroinflammation alters the production of neurotransmitters responsible for mood, sleep and appetite. It also impairs neurogenesis, the process by which our brain forms new neural pathways. These new pathways are important when it comes to developing and maintaining new behaviours and lifestyle patterns that help with long-term weight maintenance. If neurogenesis is impaired it is difficult, if not impossible, to develop new behaviours and sustain them long-term.
The healthy function of these organs is critical to losing fat and maintaining a healthy weight. It’s easy to see why weight loss is not a just matter of reducing calories and why it’s so important to manage inflammation.
What can you do to reverse the damage?
It’s essential to restore a healthy gut microbiota in order to reduce inflammation.
Many people mistakenly believe that restoring gut health is as simple as eating fermented foods and taking a probiotic – but this can actually do more harm than good if your gut is unhealthy. It’s important to educate yourself on what’s best for you so that you don’t worsen inflammation and inadvertently reduce your chances of successfully losing weight. More information here – fermented food and probiotics blog
Here are some tips to help you improve gut health and reduce inflammation:
Remove all foods that cause inflammation such as sugar or sweeteners, saturated fats, vegetable oils, food additives, alcohol, gluten, processed foods and any foods you have an intolerance to. If weight loss is your goal, then “moderation” it not a good idea when it comes to these foods.
Incorporating intermittent fasting and/or a low carb diet. These have been shown to reduce inflammation as well as having many other health benefits, however, they don’t come without risks. If done incorrectly or in those with certain medical conditions, they can cause hormonal problems that make matters much worse in the long-term. It’s important that you do your research to find what’s best and safest for you.
Manage stress. Various relaxation techniques such as yoga, meditation and deep breathing have been shown to increase healthy gut bacteria and reduce inflammation.
Get 20 minutes of sunlight each day. Vitamin D is a potent anti-inflammatory agent that comes from the sun, so it’s free!
Perform some form of moderate exercise for 30 minutes each day. Regular exercise has been shown to reduce CRP and increase neurogenesis.
Take anti-inflammatory supplements such as curcumin, fish oil, green tea extract, quercetin, prebiotics and probiotics (these should not be added for at least two weeks!).
Make sure you get 7-8 hours of uninterrupted sleep each night. Even one night of poor sleep can change the gut microbiota.
If you are resistant to weight loss, or are middle-aged, have hormonal problems or have symptoms or conditions that are driven by inflammation or cause inflammation, you may need a formal gut-healing protocol such as The Biome Protocol. The protocol is a comprehensive plan that helps restore the gut microbiota and address the factors involved in weight loss. It is practitioner supervised which means the protocol can be adapted to your individual needs. It contains information on how to safely implement various dietary modifications in order avoid potential complications and ensure that you get the best possible results.
Weight gain or resistance to weight loss may be a sign of nutrient deficiencies or the inability to effectively utilise nutrients. The protocol includes three nutrient formulations that contain a range of nutrients, antioxidants, anti-inflammatory and herbal ingredients found to improve gut health, reduce inflammation and support the functions that assist with weight loss. More information on The Biome Protocol can be found here
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