Why what you eat matters more than you think
Most people know to avoid junk food. What’s less obvious is that several foods marketed as healthy — refined vegetable oils, low-fat products, fruit juice — may be quietly driving up inflammation. The story with red meat and dairy is also more nuanced than most articles suggest.
This guide covers the main dietary triggers of chronic inflammation, what the research says about joint inflammation specifically, and which nutrients may support your body’s ability to manage it.
What is chronic inflammation?
Acute inflammation is protective. When you sprain your ankle and it swells up, that’s your immune system sending white blood cells to the area. It resolves within days and serves a purpose.
Chronic inflammation is different. It’s a persistent, low-grade immune response that doesn’t switch off. Research links it to heart disease, type 2 diabetes, arthritis, and cognitive decline.
Diet is one of the most significant and most actionable drivers of chronic inflammation.
8 foods that cause inflammation
1. Sugar and refined carbohydrates
Added sugar drives inflammation by spiking blood glucose and triggering the release of pro-inflammatory cytokines. A 2013 review in Nutrition Reviews found that high-glycaemic diets consistently raise C-reactive protein (CRP), a primary marker of systemic inflammation.
This includes obvious sources like sweets, soft drinks, and pastries, but also white bread, white rice, and most breakfast cereals. The issue is the rapid glucose response, not sugar in whole fruit, where fibre slows absorption.
On UK food labels, watch for glucose-fructose syrup, dextrose, maltose, and any ingredient ending in “-ose”.
2. Refined seed and vegetable oils
Sunflower oil, corn oil, and soybean oil are high in omega-6 fatty acids. Your body needs omega-6, but the modern diet delivers far too much relative to omega-3. A 2016 review in Nutrients found this imbalance promotes a pro-inflammatory state at the cellular level.
The ideal omega-6 to omega-3 ratio is roughly 4:1. The average UK diet sits closer to 15:1, heavily skewed toward inflammation.
Better alternatives include extra virgin olive oil, avocado oil, or butter from grass-fed cattle.
3. Ultra-processed foods
Ready meals, packaged crisps, reconstituted meat products, and most fast food are typically high in refined carbohydrates, seed oils, and additives, while being low in fibre and antioxidants.
A large 2018 study in The BMJ, following over 100,000 adults, found that each 10% increase in ultra-processed food consumption was associated with significantly higher inflammatory markers. The effect was consistent across age groups.
A useful rule of thumb: if a product has more than five ingredients you can’t picture in their natural form, it’s probably ultra-processed.
4. Alcohol
Alcohol is a pro-inflammatory agent. It disrupts the gut barrier, allowing bacterial endotoxins to pass into the bloodstream and trigger a systemic immune response. A 2010 review in Alcohol Research found that chronic alcohol consumption elevates CRP, interleukin-6, and tumour necrosis factor-alpha (TNF-α), all key markers of inflammation.
The gut-inflammation link is particularly significant here. Even moderate regular drinking can compromise intestinal integrity over time.
5. Trans fats
Partially hydrogenated oils are the source of artificial trans fats. They raise LDL cholesterol and inflammatory markers simultaneously. A 2001 study in the American Journal of Clinical Nutrition found they were among the most reliably pro-inflammatory dietary components tested.
Artificial trans fats have largely been removed from UK products following regulatory pressure, but they can still appear in some imported goods. Check labels for “partially hydrogenated” oils.
6. Artificial sweeteners
The evidence here is less settled than with sugar, but a 2021 study in Cell found that saccharin and sucralose altered gut bacteria composition in ways linked to metabolic dysfunction and inflammatory signalling. The mechanism appears to be gut microbiome disruption rather than a direct inflammatory effect.
On UK labels they appear as: aspartame (E951), sucralose (E955), acesulfame K (E950), saccharin (E954), and neotame (E961).
7. Dairy
Dairy’s effect on inflammation varies significantly between individuals. For most people, moderate dairy consumption doesn’t raise inflammatory markers. Some research even suggests fermented dairy such as yoghurt and kefir may be mildly anti-inflammatory due to their probiotic content.
Those with lactose intolerance or sensitivity to casein (a milk protein) may experience gut inflammation after consuming dairy. If you suspect dairy is a trigger for you, a 4-week elimination trial followed by reintroduction is the most reliable way to find out.
8. Processed and charred red meat
Red meat’s relationship with inflammation is more complicated than often presented. Unprocessed cuts aren’t consistently inflammatory in the research. The bigger concerns are processing and cooking method.
Processed meats including bacon, sausages, salami, and deli meats are more reliably linked to elevated inflammatory markers. Cooking any meat at very high temperatures produces advanced glycation end products (AGEs), which promote oxidative stress and inflammation. Lower-temperature cooking methods reduce AGE formation considerably.
Foods that cause inflammation in the joints
Joint inflammation is a specific concern for many people, particularly those with arthritis or over 50. Several of the foods above have documented effects on joint health.
Sugar and refined carbohydrates raise uric acid levels, increasing gout risk. A 2020 study in Arthritis & Rheumatology found that high-sugar diets were associated with greater joint pain scores in patients with rheumatoid arthritis.
Seed oils high in omega-6 contribute to the production of arachidonic acid, a precursor to pro-inflammatory compounds that directly affect joint tissue. This is a specific pathway that targets joints, distinct from the general systemic effect.
Alcohol is a well-documented gout trigger. Research published in The Lancet (2004) found beer carried the highest risk of gout flares among alcoholic drinks, followed by spirits, with wine showing a much weaker association.
If joint inflammation is your primary concern, reducing sugar, processed meats, and seed oils while increasing omega-3 intake tends to have the clearest effect in the research.
What may help reduce inflammation
Diet works in both directions. The same research base that identifies inflammatory foods also points to patterns associated with lower inflammation. Foods with consistent anti-inflammatory evidence include:
- Oily fish (salmon, mackerel, sardines): high in EPA and DHA omega-3s, which directly counter the arachidonic acid pathway
- Leafy greens (spinach, kale, Swiss chard): rich in antioxidants and polyphenols that reduce oxidative stress
- Berries: high in anthocyanins, associated with reduced CRP in multiple studies
- Extra virgin olive oil: contains oleocanthal, which research suggests has COX-inhibiting properties similar in mechanism to ibuprofen
- Walnuts: one of the few plant foods with meaningful omega-3 content (ALA), alongside anti-inflammatory polyphenols
- Turmeric: curcumin has well-documented anti-inflammatory properties in research, though bioavailability from food alone is low without a fat source or black pepper
Nutrients that research associates with inflammation support
Beyond diet, certain nutrients have specific roles in the body’s inflammatory response. Three are particularly well-studied for adults in the UK.
Vitamin D3 and K2
Vitamin D deficiency is widespread in the UK. The NHS estimates around 1 in 5 adults has low levels, and that figure rises sharply over 50 and in winter months. Deficiency is associated with elevated inflammatory markers. A 2014 meta-analysis in Public Health Nutrition found an inverse relationship between vitamin D status and CRP: lower vitamin D consistently corresponded to higher inflammation. K2 works alongside D3 to direct calcium appropriately, and research suggests K2 may independently reduce inflammatory cytokines. Our Vitamin D3K2 supplement combines both with zinc and boron.
Magnesium
Around 70% of UK adults don’t reach the recommended daily intake for magnesium. It plays a role in over 300 enzymatic reactions, including several that regulate inflammatory signalling. A 2018 review in Nutrients found that low magnesium intake was independently associated with higher CRP and IL-6 levels, two of the most commonly used inflammation markers. Magnesium glycinate is the most bioavailable form, better absorbed than oxide or citrate with less digestive discomfort.
NAC (N-Acetyl Cysteine)
NAC is a precursor to glutathione, the body’s primary antioxidant. Oxidative stress and inflammation are closely linked: when glutathione is depleted, inflammatory cascades continue unchecked. A 2017 review in Cell Journal found NAC supplementation reduced oxidative markers and inflammatory cytokines across multiple study populations. Our NAC+ supplement provides 600mg per capsule.
Gut health
The gut is increasingly recognised as a central regulator of systemic inflammation. A disrupted gut microbiome, caused by processed foods, alcohol, and antibiotics, increases intestinal permeability and allows bacterial endotoxins into the bloodstream, triggering inflammation throughout the body. Supporting the gut microbiome through diet and targeted supplementation may help address inflammation at its root. Biome Bliss is our gut health supplement formulated to support microbiome diversity and intestinal barrier function.
Frequently asked questions
What are the worst foods for inflammation?
The foods most consistently linked to chronic inflammation are added sugar, refined seed oils (sunflower, corn, soybean), ultra-processed foods, alcohol, and artificial trans fats. Processed meats are also a concern. The common thread is that these foods either spike blood glucose rapidly, disrupt the omega-6 to omega-3 balance, or damage the gut microbiome.
What foods cause inflammation in the joints?
Sugar and refined carbohydrates raise uric acid and worsen joint pain, particularly in gout and rheumatoid arthritis. Seed oils high in omega-6 promote compounds that directly inflame joint tissue. Alcohol, particularly beer, is a well-documented trigger for gout flares. Reducing these while increasing oily fish and leafy greens tends to have the most consistent effect on joint symptoms.
Does dairy cause inflammation?
For most people, dairy doesn’t significantly raise inflammatory markers. Those with lactose intolerance or casein sensitivity may experience gut inflammation after consuming it. Fermented dairy such as yoghurt and kefir may actually be mildly anti-inflammatory. If you suspect dairy is an issue, a 4-week elimination trial followed by careful reintroduction is the most reliable way to find out.
Does spicy food cause inflammation?
Generally, no. Capsaicin, the active compound in chillies, is actually being studied for anti-inflammatory properties. Most whole spices are not pro-inflammatory. The concern with “spicy food” usually relates to heavily processed spicy snacks, not the spices themselves.
What foods cause gut inflammation?
Ultra-processed foods, alcohol, artificial sweeteners, and low-fibre diets are the main contributors to gut inflammation. They disrupt the gut microbiome and compromise the gut barrier, allowing bacteria to enter the bloodstream and trigger systemic inflammation. Increasing fermented foods and dietary fibre is consistently associated with improved gut barrier integrity. Our guide to the worst foods for gut health goes deeper on this.
Can changing my diet reduce inflammation?
Research suggests it can, though the degree varies by individual and condition. Reducing ultra-processed foods and added sugar while increasing oily fish, vegetables, and whole foods is consistently associated with lower inflammatory markers in clinical studies. Changes are typically measurable within 4 to 8 weeks on a sustained dietary shift.
References
- Barbaresko J, et al. (2013). Dietary pattern analysis and biomarkers of low-grade inflammation: a systematic literature review. Nutrition Reviews.
- Simopoulos AP. (2016). An increase in the omega-6/omega-3 fatty acid ratio increases the risk for obesity. Nutrients.
- Fiolet T, et al. (2018). Consumption of ultra-processed foods and cancer risk. The BMJ.
- Molina PE, et al. (2010). Alcohol abuse: critical pathophysiological processes and contribution to disease burden. Alcohol Research.
- Mozaffarian D, et al. (2001). Dietary intake of trans fatty acids and systemic inflammation in women. American Journal of Clinical Nutrition.
- Suez J, et al. (2021). Personalized microbiome-driven effects of non-nutritive sweeteners on human glucose tolerance. Cell.
- Choi HK, et al. (2004). Alcohol and the risk of gout. The Lancet.
- Holick MF. (2014). Vitamin D and inflammation. Public Health Nutrition.
- Nielsen FH. (2018). Magnesium deficiency and increased inflammation: current perspectives. Nutrients.
- Mokhtari V, et al. (2017). A review on various uses of N-Acetyl Cysteine. Cell Journal.
This article is for informational purposes only and does not constitute medical advice. If you have a chronic health condition or are taking medication, speak with your GP before making significant changes to your diet or starting any new supplements.
