I've mentioned chronic inflammation /metainflammation in my posts quite a bit - so if you're wondering what it's actually all about this post is for you!!
The theory of inflammation goes back to roman times, its the reaction of the body to injury or infection
The discovery of chronic low grade/ systemic inflammation is relatively new though, and has shaped a huge amount of research since
In 1993 a Turkish researcher discovered that overweight patients had low levels of chronic inflammation throughout the body, mostly centred around blood vessels and fat cells
He theorised that it could be the underlying cause of heart attacks, strokes, and insulin resistance, and coined the term 'meta inflammation'
Since then much more research has been done, and meta inflammation has been linked as a potential cause of many diseases, including heart disease, dementia, depression, autoimmune diseases, lung disease, allergy, and even cancer
Its also one of the main drivers of severe covid infection, with the inflammatory response to the covid virus causing most of the damage - explaining part of why obesity, Western diet, metabolic syndrome and vitamin d deficiency are associated with worse outcomes, whereas plant based diets and other lifestyle factors appear to be protective
The theory behind food and inflammation is intriguing:
humans have an effective immune response to protect from 'invaders'
as food is a foreign molecule (ie not part of the body), in order to tolerate it, the body has to recognise it as harmless
prior to the industrial revolution, human diets were fairly stable for millenia - ie whole foods, mostly plants, with small amounts of wild game, free range eggs, and dairy (in some cultures), and with minimal processing (think stone ground flour, pressed oils etc)
since then, and particularly in the last 50 years, foods have changed dramatically due to technology and new processing methods
the rapid rise in ultra processed foods has correlated with a rise in chronic disease. As processed foods are 'new', the body sees them as invaders, and mounts an immune response when we eat them Over time if these foods are eaten often, chronic inflammation develops
As processed foods are relatively recent, the body does not recognise these, and sees them as dangerous - which triggers off an inflammatory response by the immune system
If these are eaten only occasionally the body can switch off the response, however if inflammatory foods are eaten often, the inflammation becomes chronic and over time causes disease
This inflammation can also be reduced, by altering food choices, as well as other lifestyle factors (exercising, getting enough sleep, managing stress, minimising exposure to toxins such as cigarette smoke, car fumes, household chemicals, plastics etc)
In recent years science has been able to measure the effect of different foods on the body, by checking blood markers of inflammation after people eat (ie CRP, IL6, TNF alpha)
Other tests like HDL (good cholesterol), leptin, and adiponectin can also be measured, these are 'anti inflammatory markers' ie switch off inflammation
Interestingly, virtually all the foods that trigger inflammation when eaten, are 'modern' foods ie highly refined grains, ultra processed foods etc
The amount also matters - very small amounts of added sugar (as would have been eaten traditionally) do not trigger high levels of inflammation, whereas large amounts do. The same goes for things like fruit juices and alcohol
The farming methods of animal products appears to affect inflammatory levels - wild game, shellfish, and free range/pasture fed meat are less inflammatory than intensively farmed meat where animals are fed high calorie diets and cannot roam (ie caged hens, grain fed cows or pigs) This seems to be mostly related to the levels of saturated fat in their meat
The dietary inflammatory index has been developed as a highly validated replicable measure of how inflammatory different foods are, and not surprisingly whole plant foods in particular green veges are the most anti-inflammatory, Highly refined carbs (ie 'white' foods such as white rice, white flour, and some potatoes), refined sugar, saturated fat, and alcohol are the most inflammatory (see my seperate post on this)
So what's an anti-inflammatory diet? Basically think of trying to eat a rainbow of foods as close to what they are like in nature as possible. Aim for most of your diet to be whole plant foods as these are the most anti-inflammatory
Aim for 3-5 servings of veges each day (with some of these being dark green and leafy veges), and 2-3 servings of fruit
Include around 3 servings of whole grains (ancient grains are better tolerated by some people than wheat, this is fairly individualised)
Legumes are also great to include as these have a particularly beneficial effect on gut health, which is closely linked to inflammation (see seperate post on this)
Fibre is highly anti-inflammatory (also largely due to effect on gut health), and legumes and whole grains are excellent sources of fibre Small amounts of oily fish, free range eggs, and olive oil are fine
Including a variety of herbs and spices is also great, in particular garlic, onion ginger, turmeric, cinnamon, green tea, black pepper, oregano, rosemary and potentially coffee
Try to avoid or significantly limit ultra processed foods, refined carbs, added sugar, refined seed oils, red meat, and saturated fat. If you do eat red meat try get wild meat, or pasture fed over grain fed (and ideally organic)
Avoiding grazing, and fasting overnight (ie time restricted eating) is also helpful
'Eat whole foods, mostly plants, not too much'!