This post is part of a series that dissects what kinds of inflammation people get, the diseases and risks associated with such inflammation, and how we could dial it down.
What is Interleukin-8?
Interleukin 8 (IL-8) is a ‘chemokine’ produced by various immune cells. Chemokines attract other immune cells to a specific area. IL-8 an important part of our immune response .
IL-8 attracts other cells that are the real muscle of the immune system: neutrophils (also attracts eosinophils and basophils). Neutrophils consume bacteria by engulfing them. IL-8 can release molecules like histamine to facilitate the attraction of neutrophils .
IL-8’s Role in Disease
IL-8 is also known to be a potent promoter of angiogenesis, which is the growth of blood vessels. This is what helps cancer grow. It also increases the proliferation and survival of cancer cells.  Indeed, increased IL-8 is associated with many cancers. Recently, IL-8 was shown to increase hormonal activity in prostate cancer cells (which helps them grow). IL-8 can also cause resistance to chemotherapy in cancer cells. 
IL-8 contributes to forming plaques in our arteries . TNF, IL-1b, and IL-8 enhance the binding of cholesterol (LDL) to blood vessels and increases the adhesion of immune cells in these vessels. Both of these events contribute to atherosclerosis .
Important Contributory Factors
IL-8 is released by fat cells and is elevated in obese people and correlated with fat mass .
IL-8 and the Brain
Higher IL-8 predicted smaller gray matter volumes in the hippocampus .
IL-8 also exerts neuroprotective properties . IL-8 might be involved in the biological mechanisms mediating resilience to anxiety. In this way, it can reduce suicide among people with psychiatric conditions .
Diseases Associated With IL-8
- Heart disease 
- Cancer  – Prostate Cancer , Breast Cancer , Colorectal Cancer , Liver Cancer, Thyroid Cancer , Myeloma , among others.
- Pain [12, 13]
- CFS (post infection type)  and Fibromyalgia 
- Depression , Bipolar (could be from lithium) , Schizophrenia  – Also, children had a higher risk for schizophrenia when pregnant mothers had elevated IL-8 . High IL-8 reduced the likelihood of positive responses to antipsychotic medication .
- Migraines 
- Alzheimer’s 
- IBS , Colitis , Crohn‘s 
- Thyroiditis 
- Rheumatoid Arthritis [26, 27]
- Multiple Sclerosis , Lyme , ALS 
- Behcet’s 
- Asthma and COPD , Allergic Rhinitis  (not the main cytokine)
- Sleep apnea  – probably elevated because of hypoxia
- Osteoporosis (post-menopausal) 
- Psoriasis  and Eczema 
- Gingivitis 
- Vitiligo 
Top Ways to Inhibit IL-8
- Calorie Restriction 
- Fasting 
- Wim Hof Breathing/Meditation 
- Quercetin [43, 44, 45, 46, 47]
- Bromelain  (promising, removes receptors -CD128a+b from neutrophils- unique mechanism?)
- Probiotics: B. infantis, L. casei and L. lactis , B. Longum, L. Bulgaricus , S. Boulardii , B. subtilis 
- Resveratrol (500mg, with 5g leucine) 
- Luteolin [38, 53]
- Apigenin 
- Aspirin 
- Cinnamon /Sodium Benzoate
- Fisetin , not activated basophils 
- Cod liver/fish oil 
- Licorice 
- Curcumin 
- Black Cumin Seed Oil/Thymoquinone 
- Andrographolide  (by inhibiting NF-kB)
- Vitamin D3 
- Jasmine Tea/EGCG
- Zinc 
- Red Yeast Rice/Statins 
- Theaflavins  (“Potent”)
- Artemisinin 
- Vitamin E  (alpha-tocopherol prevents UVA-induced IL-8 increase)
- Cortisol/Glucocorticoids/Dexamethasone 
- alpha-msh 
- ACTH 
- DHEA 
- Progesterone 
- Estradiol  – in cystic fibrosis
- LLLT [74, 75, 76]
- ACE inhibitors  – blood pressure lowering drugs. Many natural products are also ACE inhibitors.
- Theanine  (via NF-kB)
- Rutin 
- Milk thistle/Silymarin 
- Phytic acid  – in plant-based foods
- Oat /Oat polyphenols 
- Ginkgo 
- Grape Seed Extract 
- Parthenolide/Feverfew  – (via inhibiting NF-kB, TNF, and IL-1b)
- Echinacea , Danshen , Kaempferol , Chrysin , Caffeic acid , Sumac ,
- Doxycycline 
- Oxidative stress  (specifically, H2O2) – but H2O2 inhibits IL-8 production in neutrophils 
- Sun/UVB  + UVA 
- Exercise  – small and only locally in muscle.
- Obesity  – IL-8 is released by fat cells.
- Smoking 
- Estradiol  – in breast tissue
- Salmonella 
- Angiotensin II 
- Homocysteine 
- Lithium  (in intestinal cells)
- Resistant starch/Butyrate  (intestinal cells)
- Asian Ginseng (some parts)