Can food affect inflammation?
We're often told that certain foods are anti-inflammatory and that we should avoid others for being inflammatory. But what does this even mean, and how much of an influence do foods really have?
Inflammation is an immune response by our body against things like injury and infection. And the term inflammation can be quite literal, with sites of inflammation potentially looking red, raised and even feeling hot to touch -think about getting a cut on your skin and how it looks a short while afterwards. In the short term, and in specific areas, inflammation is important for healing. However, long-term inflammation across wider parts of the body can be too much of a good thing. Chronic, low-grade inflammation can be associated with inflammatory bowel disease, some auto-immune and "lifestyle" diseases like type 2 diabetes. In some cases, it isn't always clear if inflammation is a risk factor or a result of these conditions.
Rapeseed oil and omega-6
Rapeseed, or Canola oil is often branded as being pro-inflammatory due to it's high content of omega-6. Omega-6 is a polyunsaturated fatty acid, and is considered to be "essential" meaning that we cannot produce it ourselves, so need to get it from our diet. It is similar in structure to omega-3, a fatty acid found to have benefits to brain health and is considered anti-inflammatory. Omega-6 is associated with benefits to cardiovascular health similar to omega-3. However, it is often seen as inflammatory for two reasons. Firstly, because our diet is more likely to have higher levels of omega-6 than omega-3, this is thought to negate the benefits of omega-3 through upsetting the balance (1). Second, because omega-6 is converted into arachidonic acid in the body. Arachidonic acids can be broken down into molecules that may promote inflammation. However, this break down doesn't necessarily happen in the body.
The evidence that we have shows no link between rapeseed oil (or other vegetable oil) intake and chronic disease prevalence. Additionally, rapeseed oil is a source of omega-3, even if at lower levels compared to omega-6. Although awareness of portion sizes of cooking oil is probably sensible, rapeseed oil is a safe, healthy alternative to olive oil, and can be a more budget-friendly option too.
Dairy and saturated fats
Dairy contains saturated fats, which are associated with raised LDL levels and increased risk of cardiovascular disease. Because of these high saturated fat levels, dairy is often labelled pro-inflammatory. However, dairy (excluding butter) hasn't been shown to have this link with cardiovascular disease or inflammation. This difference is thought to be due to the structure of dairy products stopping the saturated fat from being digested in the same way. Butter has been churned so it loses this beneficial structure. If you choose not eat dairy for sustainable or ethical reasons, that's absolutely fine. But if you're avoiding it for fear of inflammation, it may be worth reconsidering (3).
Building a anti-inflammatory diet
As mentioned above, omega-3s can have anti-inflammatory effect. Plant foods may also have an anti-inflammatory effect thanks to compounds such as polyphenols and vitamins that down-regulate inflammatory pathways (4). This includes antioxidant-rich fruits and vegetables, but also nuts and seeds, and fibre-filled wholegrains. Certain herbs and spices can have higher concentrations of some of these compounds -which is where that flavour comes from -as well. This anti-inflammatory effect builds up over time, so it is better to aim to eat a variety of fruits and vegetables every day rather than relying on supplementing on things like turmeric occasionally.
It is unlikely that a single food is going to increase or decrease inflammation levels in your body. Instead, think about your overall dietary and lifestyle habits. A varied diet containing fruits and vegetables, herbs and spices, and sources of omega-3 will put you in better stead than focusing on cutting out fear-foods or buying lots of superfood powders.
Want to know more about omega-3? Read my plant-based guide to omega-3s here.
References
- Stanley, J.C., Elsom, R.L., Calder, P.C., Griffin, B.A., Harris, W.S., Jebb, S.A., Lovegrove, J.A., Moore, C.S., Riemersma, R.A. and Sanders, T.A., 2007. UK Food Standards Agency Workshop Report: the effects of the dietary n-6: n-3 fatty acid ratio on cardiovascular health. British Journal of Nutrition, 98(6), pp.1305-1310.
- Rett, B.S. and Whelan, J., 2011. Increasing dietary linoleic acid does not increase tissue arachidonic acid content in adults consuming Western-type diets: a systematic review. Nutrition & metabolism, 8(1), pp.1-15.
- Wolrich, J., 2021. Food isn't Medicine. Vermillon.
- Saunt, R. and West, H., 2019. Is Butter a Carb? Piakus.
