3 Common Foods That Can Cause Inflammation

Inflammation is a perfectly natural process of the body's immune system that helps to fight off infections, heal injuries, and defend against toxins. We would be pretty lost without it and in all honesty, we wouldn’t last 5 minutes.

However, when inflammation becomes chronic - ie long term without subsiding and gradually getting worse, it can lead to various health problems including heart disease, diabetes, and arthritis (Harvard Health Publishing, 2020). It is the catalyst and driver of most degenerative disease. All of the issues that plague our health care services are, to some degree inflammatory issues.

Diet plays a significant role in influencing inflammation levels in the body. Some foods are known for their anti-inflammatory properties, such as oily fish, leafy greens and berries, while others can trigger or worsen inflammation.

So what are the worse offenders in our diet that are really worth cutting out?

Refined Carbohydrates, Sugar and High-Fructose Corn Syrup

Ok, not a huge surprise to anyone I am sure, but an important place to start. Refined sugar (sucrose) and high-fructose corn syrup (HFCS) are prevalent in many diets, commonly found in fizzy drinks, baked goods, and many processed foods. Thankfully here in the UK HFCS is not an issue, but for those of you in the US, that stuff prolific and sneaks into almost everything!

Both additives have been linked to increased inflammation, insulin resistance, and obesity (Zhang et al., 2017). High intake of these sweeteners can trigger the release of inflammatory cytokines (communication proteins used by our immune system to relay different messages).

Moreover, studies have demonstrated that sugar and HFCS contribute to the production of advanced glycation end products (AGEs), which can further stimulate inflammatory processes (Uribarri et al., 2010). These are substances that are formed when proteins or fats combine with sugars. This process is associated with accelerated cellular ageing, and ageing of the skin. 

A study by Zhang et al. (2017) found that diets high in refined sugars led to increased levels of inflammatory markers such as C-reactive protein (CRP) in the blood. This marker is usually the only sign that there is any kind of inflammatory issue. Often chronic inflammation that drives disease is sub clinical - ie it leaves no clues unless we look for it.

Additionally, a 2014 study by Della Corte et al. linked high sugar consumption with non-alcoholic fatty liver disease (NAFLD), a condition strongly associated with increased inflammation. This is a condition that responds incredibly well to the removal of refined carbohydrates.

Reducing consumption of sugary drinks and snacks, and reading labels to avoid foods high in added sugars, are effective strategies for minimising the risk of inflammation-related conditions.

As always, I advise that you ditch the white. White bread. White rice. White pasta. These are similar to refined sugars and I would add these to the list and bundle them into the sugar group.

These carbohydrates have a high glycemic index, which means they lead to rapid spikes in blood sugar levels (and yessssss I know that blood sugar peaks and troughs are normal - it is the rate and the extent to which it happens that is the issue).

This aggressive spike can prompt an inflammatory response as high blood glucose levels accelerate the production of free radicals and inflammatory cytokines (Ludwig, 2002).

Research shows that a diet high in refined grains is linked to higher levels of inflammatory markers like CRP, mentioned above.

A longitudinal study by Hajihashemi et al. (2014) revealed that participants with the highest intake of refined grains had significantly higher levels of CRP compared to those with the lowest intake.

Switching from refined grains to whole grains can help manage blood sugar levels and reduce inflammation. Whole grains contain more fiber, which has been shown to lower CRP and inflammation (Qi et al., 2006).

Seed Oils

Ok, this one ruffles some feathers, but the evidence base is pretty clear. Seed oils, commonly referred to as vegetable oils, such as soybean, sunflower, and corn oil, are absolutely everywhere in modern diets and are frequently used in cooking and food processing.

The problem is, these oils are high in omega-6 polyunsaturated fatty acids, which, although essential for health, can promote inflammation when consumed in large amounts relative to omega-3 fatty acids (Simopoulos, 2008).

I know I talk about this all of the time, but with good reason. The imbalance of omega-6 and omega-3 fatty acids contributes to the pathogenesis of many diseases, including cardiovascular diseases, cancer, and inflammatory and autoimmune diseases. It is a massive driver of inflammation.

The typical Western diet tends to be disproportionately high in omega-6 fatty acids compared to omega-3 fatty acids, with ratios as elevated as 15:1, whereas a healthier ratio would be closer to 4:1 or even 2:1 (Simopoulos, 2008). Or if you look at the likes of Professor Bill Lands, even 2:1 in the opposite direction!

Excessive intake of omega-6 fatty acids can lead to the production of pro-inflammatory prostaglandins, leukotrienes etc, and this elevated omega-6/omega-3 ratio has been linked to increased levels of inflammation and an increased risk of chronic diseases (Patterson et al., 2012).

Furthermore, the processing of these oils can result in the formation of trans fats and other oxidation products, which are recognised for their pro-inflammatory properties. A study by Patterson et al. (2012) noted that high consumption of these oxidised fats could impair cellular function and exacerbate inflammatory responses.

To reduce the risk associated with high omega-6 fatty acid consumption, it is advisable to limit the use of common vegetable oils high in omega-6 fatty acids. Increase the intake of sources rich in omega-3 fatty acids, such as fatty fish like salmon and mackerel, to improve the omega-6 to omega-3 ratio. Then finally to use oils with a better balance of fatty acids, such as olive oil, which is high in monounsaturated fats and has anti-inflammatory properties. I have written and recorded plenty on that, so won’t go down that rabbit hole here.

Processed Meat

Ok, so I am no vegetarian thats for sure, but you wont see me knocking back a salami stick or pack of bacon any time soon. Processed meats (e.g., sausages, deli meats and the like) have been associated with increased levels of inflammation. This is not due to the fact that they are meat, but to do with the fact that they are processed and packed with substances such as nitrates, unholy amounts of sodium, preservatives, stabilisers and everything in between.

They also contain compounds such as advanced glycation end products (AGEs), mentioned earlier which can exacerbate inflammatory processes.

A meta-analysis by Wang et al. (2017) indicated that high consumption of processed meats is associated with increases in inflammatory markers, including interleukin-6 (IL-6) and CRP.

Plus there are known colorectal cancer risks there too.

Conclusion

Diet significantly influences inflammation levels in the body. Consuming high amounts of sugars, refined carbohydrates, seed oils and processed meats has been linked to increased inflammatory responses.

By understanding these relationships and making informed dietary choices, individuals can effectively manage inflammation and reduce their risk of chronic diseases. Adhering to a diet rich in whole, nutrient-dense foods and low in processed ingredients is crucial for maintaining optimal health and preventing inflammation-related conditions.

Thankfully, if you follow my recipes and general guidance to eating patterns, you are sorted!

References

Della Corte, K.W., et al. (2014). Effect of dietary sugar intake on biomarkers of subclinical inflammation: a review of the literature. The American Journal of Clinical Nutrition, 100(3), pp. 725-739.

Hajihashemi, P., et al. (2014). Prospective study of different types of dietary fiber and risk of cardiovascular disease: Tehran Lipid and Glucose Study. Nutrition, Metabolism & Cardiovascular Diseases, 24(12), pp. 1238-1245.

Harvard Health Publishing. (2020). Understanding Acute and Chronic Inflammation.

Ludwig, D.S. (2002). The glycemic index: physiological mechanisms relating to obesity, diabetes, and cardiovascular disease. JAMA, 287(18), pp. 2414-2423.

Patterson, E., et al. (2012). Health implications of high dietary omega-6 polyunsaturated fatty acids. Journal of Nutrition and Metabolism, 2012, 539426.

Qi, L., et al. (2006). Dietary fibers and glycemic load, obesity, and plasma adiponectin levels in women with type 2 diabetes. Diabetes Care, 29(7), pp. 1501-1505.

Simopoulos, A.P. (2008). The importance of the omega-6/omega-3 fatty acid ratio in cardiovascular disease and other chronic diseases. Experimental Biology and Medicine, 233(6), pp. 674-688.

Uribarri, J., et al. (2010). Advanced glycation end products in foods and a practical guide to their reduction in the diet. Journal of the American Dietetic Association, 110(6), pp. 911-916.e12.

Wang, X., et al. (2017). Red and processed meat consumption and risk of inflammatory diseases: a meta-analysis of cohort studies. Clinical Nutrition, 36(3), pp. 661-667.

Zhang, Y., et al. (2017). Fructose consumption and the risk of developing hypertension, diabetes, and obesity. Journal of Hypertension, 35(2), pp. 449-461.