UNDERSTAND DIET AND INFLAMMATION

Inflammation has become somewhat of a buzzword in nutrition circles over recent years; in fact it’s become so popular that most people would have been told to avoid ‘X food group’ because it’s apparently the cause of their inflammation, or sipped on an ‘anti-inflammatory smoothie’ from the local café.

I am sure you’ve heard certain foods can contribute to inflammation, that the latest dietary trend is ‘anti-inflammatory,’ or even that new wonder supplements can ‘cure’ inflammation.

I’ve decided to add my drop of water to the ocean, with the hope of clearing the water. So, let's break it down!

When people discuss inflammation, they are broadly talking about your body’s ability to fight infection or illness. There are two types of inflammation – acute and chronic.  It’s important to differentiate between these types of inflammation as one is a normal bodily response, which is key to long term health, while the other can become debilitating and trigger further health consequences. 

Acute inflammation, also referred to as a local response, is generally considered the ‘good’ type of inflammation. This is a normal bodily response and key in fighting tissue damage, combating foreign viruses and bacteria, and regulating metabolic damage. Imagine you got a cut on your foot: your body would initiate acute inflammation around the damage, causing the area to swell, fighting infection and helping to repair the tissue damage.

Chronic inflammation is a longer-term response. When your body’s inflammatory response goes on for a long time or is high grade it will begin to trigger further harmful responses. This can also be referred to as systemic inflammation. From a dietary perspective, coeliac disease is perhaps the simplest to understand; in individuals with coeliac disease the body will trigger an inappropriate immune response to the wheat-based protein gluten. Coeliac disease is an autoimmune disease where the body attacks its own tissues and organs. If not correctly managed by adhering to a gluten-free diet this will become chronic inflammation.

From a research perspective there are a few different inflammatory biomarkers that are monitored.

C-reactive protein (CRP) – arguably the most accurate measure of inflammation, CRP is a protein which is made by the liver in response to inflammatory cytokines. It rises quickly and falls back to normal levels once the inflammatory stimulus is removed.

Interleukin 1,2, and 6 – the other commonly measured biomarker in inflammation, this is a powerful pro-inflammatory cytokine which is released in acute phase inflammation.

Tumour necrosis factor alpha (TNF-alpha) – is a cell signalling cytokine which is involved in early-stage signalling of systemic circulation.

Homocysteine – is a naturally occurring amino acid produced during the methylation process in the body. During inflammation it becomes chronically elevated.

There are several other biomarkers which can be used, however these are the primary measures. It is important to look at which biomarkers are being used to access inflammation before the findings are extrapolated to the wider population.

For example, you may see one study which assesses a particular dietary pattern, such as the Mediterranean diet - and notes a decrease in IL-6. Another study may assess the same dietary pattern and note no change in IL-6.

This inconsistency in outcomes has led to a lot of the misinformation about inflammation. Generally speaking, studies which examine multiple biomarkers are the most reputable. There is also the Dietary Inflammatory Index (DII) which was developed to access measurements of a food/compound and determine on a broader level whether it is pro- or anti-inflammatory. A lower DII will be anti-inflammatory, and a higher DII will be pro-inflammatory.

There are certain foods or food groups which if eaten regularly, and in high amounts will contribute to inflammation. Most of these foods already have strong correlations with a number of non-communicable diseases such as cardiovascular disease, hypertension, and elevated cholesterol levels. You will notice that these foods are highly processed, refined and nutrient poor.

●       Sugar sweetened beverages – sodas, fruit juices, and energy drinks.

●       Heavily processed foods, high in saturated and trans-fats – unhealthy takeaways and deep-fried foods.

●       Highly refined-low fibre carbohydrates – chocolate bars, confectionary, cakes, sweets.

●       Alcohol – beer, wine, spirits.

It’s not surprising that these foods are considered proinflammatory, no nutritionist or dietitian would promote consuming these foods in high quantities. So what about anti-inflammatory foods?

The research into inflammation and nutrition began by examining the roles of certain nutrients on the inflammatory biomarkers discussed above. There are a number of well researched nutrients in this area.

Phytochemicals - are a group of biologically active compounds found exclusively in plants. There are thousands of different phytochemicals, each exerting a different effect. A few common examples of phytochemicals are:

●       Flavonoids – these make up the majority of phytochemicals and have powerful anti-inflammatory effects. Flavonoids are found in the dark pigment of plant foods such as dark chocolate (>70%) and red wine.

●       Carotenoids – the yellow, orange, and red pigment found in plant foods, this is the nutrient that gives these foods colour and has powerful anti-inflammatory effects.

●       Omega 3 fatty acids – are a subgroup of polyunsaturated fats and have long been thought to be extremely healthy, with research over the last decade showing strong anti-inflammatory properties. Omega 3 fatty acids (w-3) are primarily found in oily fish, walnuts, and chia seeds.

●       Monounsaturated fatty acids – coming from foods such as olive oil, almonds, and avocados, these have powerful health benefits. Although not as beneficial as the polyunsaturated fats mentioned above, they still have anti-inflammatory properties.

●       Legumes, pulses, and vegetables – are a great source of insoluble fibre, which is a type of indigestible fibre that passes through your gastrointestinal tract and is used as an energy source for the bacteria living in your gut – promoting favourable strains (bifidobacterial and lactobacilli). The gut bacterial distribution is one of the biggest contributors to overall health.

●       Green tea, turmeric (curcumin), garlic, ginger – are all showing potential positive benefits but the research into these nutrients is still very young.

Anti-inflammatory diets have become somewhat of a controversial topic in nutritional science: we have a huge range of different eating behaviours, all of which claim to be the next big thing to combat inflammation. Just look to people promoting modified fasting, the ‘caveman’ way of eating, or even a vegan/plant-based diet - all of which promote very different dietary behaviours.

So, what does an anti-inflammatory diet look like? The simple answer is a diet rich in colour, flavours, and variety. If you were to delve a little deeper into this it would look to regularly incorporate the beneficial nutrients discussed above, along with ensuring you are meeting all your macro and micronutrient requirements. If a particular food or food group is removed, whether this is due to an intolerance/allergy, dislike, or ethical choice it is paramount that the individual gets these nutrients from another food source.

I hope you enjoyed reading this piece as much as I enjoyed writing it, and you understand the causes, measures, and dietary protocols involved in managing inflammation.

If you’re interested in learning a little more about this topic I would highly recommend listening to sigma nutrition radio, episode 329 which I have added as a further resource below the references.