The Healthspan Map · Immune, Inflammation & Infection
Weak immunity & chronic inflammation
Named for Weak immunity & chronic inflammation
| Nutrient or lever | Direction | Strength | Evidence type | What was found | Source |
|---|---|---|---|---|---|
| Cardio (moderate + intervals) | Do this | Strong | RCT / meta-analysis | Physical activity reduces pneumonia risk (meta-analysis, 1,044,492 participants), lowers CRP and improves vaccine response. | Physical activity & pneumonia risk (opens in a new tab) |
| Cardio / VO2max | Watch this | Strong | RCT / meta-analysis | Higher cardiorespiratory fitness/physical activity lowers pneumonia mortality (dose-response meta) and mitigates immunosenescence and inflammaging. | Fitness & infection mortality (opens in a new tab) |
| EPA/DHA (omega-3) | Eat enough of | Strong | RCT / meta-analysis | EPA/DHA supplementation lowers CRP, IL-6 and TNF-a (umbrella meta-analysis of ~148 trials) via resolvins and NF-kB inhibition. | Omega-3 & inflammation (opens in a new tab) |
| Protein | Eat enough of | Strong | Established clinical | Protein-energy malnutrition is a leading cause of secondary immunodeficiency, impairing cell-mediated immunity, antibodies and phagocytes. | Protein-energy malnutrition & immunity (opens in a new tab) |
| Sleep duration | Watch this | Strong | RCT / meta-analysis | Sleeping under 6 h raises cold susceptibility 4.2x, cuts vaccine antibody response ~50%, and drops NK-cell activity ~70%; AASM recommends >=7 h citing immunity. | Sleep duration & immunity (opens in a new tab) |
| Sleep quality (refreshed) | Watch this | Strong | RCT / meta-analysis | Poor sleep efficiency raises cold susceptibility and CRP/IL-6 (Cohen; AASM consensus). | Sleep quality & infection (opens in a new tab) |
| Ultra-processed food — cut back | Do this | Strong | Review / narrative | Higher ultra-processed food intake is consistently associated with elevated CRP and inflammatory markers. | Ultra-processed food & CRP (opens in a new tab) |
| Vitamin D | Eat enough of | Strong | RCT / meta-analysis | Vitamin D drives antimicrobial peptides; supplementation reduces acute respiratory infections. One of the three strongest immune micronutrients. | Vitamin D & respiratory infection (opens in a new tab) |
| Added Sugars | Don't overdo | Moderate | Cohort / observational | High added-sugar intake raises CRP/IL-6 via NF-kB and glycation. | "The association between sugar-sweetened beverages intake, body mass index, and inflammation in US adults", Int J Public Health 2020 (opens in a new tab) |
| Alcohol — cut back | Do this | Moderate | Review / narrative | Excess alcohol promotes adipose and systemic inflammation (IL-6/TNF-a) and impairs host defence. | Alcohol & inflammation (opens in a new tab) |
| Anchor foods | Watch this | Moderate | Review / narrative | A whole-food/Mediterranean pattern lowers IL-6 and CRP. | Mediterranean pattern & inflammation (opens in a new tab) |
| Anchor foods | Watch this | Moderate | RCT / meta-analysis | A whole-food/Mediterranean pattern lowers IL-6 and CRP. | Mediterranean dietary pattern, inflammation and endothelial function: a systematic review and meta-analysis of intervention trials, Nutr Metab Cardiovasc Dis 2014 (opens in a new tab) |
| BMI | Watch this | Moderate | Review / narrative | Visceral fat secretes IL-6 and TNF-a, raising CRP and driving chronic low-grade inflammation and impaired immunity. | Obesity & inflammation (opens in a new tab) |
| Body Roundness Index | Watch this | Moderate | Review / narrative | Central-adiposity measures track systemic inflammation (IL-6/CRP) and immune dysfunction. | Central adiposity & CRP (opens in a new tab) |
| Colours a day | Watch this | Moderate | RCT / meta-analysis | Colourful plant polyphenols and antioxidants blunt oxidative stress and inflammation. | Effect of Polyphenol-Rich Interventions on Gut Microbiota and Inflammatory or Oxidative Stress Markers, Nutrients 2025 (opens in a new tab) |
| Cook real food | Do this | Moderate | Review / narrative | Cooking from whole ingredients cuts ultra-processed additives linked to inflammation. | Home cooking avoids additives (opens in a new tab) |
| Copper | Eat enough of | Moderate | Review / narrative | Copper supports superoxide dismutase and innate immune killing; deficiency causes neutropenia and impaired immunity. | Copper & innate immunity (opens in a new tab) |
| Daily movement baseline | Do this | Moderate | RCT / trial | Regular moderate activity lowers CRP and inflammatory adipokines over 6-12 months. | Moderate exercise & CRP (opens in a new tab) |
| Falling & staying asleep | Watch this | Moderate | Review / narrative | Insomnia and fragmented sleep predict lower influenza-vaccine antibody titres and higher inflammation. | The Sleep-Immune Crosstalk in Health and Disease, Physiol Rev 2019 (opens in a new tab) |
| Folate (B9) | Eat enough of | Moderate | Review / narrative | Folate is required for immune-cell proliferation and the Th1 response. | Folate & lymphocytes (opens in a new tab) |
| Food & hand hygiene | Do this | Moderate | Systematic review | Handwashing with soap reduces respiratory infections (~24% pooled), lowering infection burden. | Handwashing & infection (opens in a new tab) |
| Iron | Eat enough of | Moderate | Review / narrative | Iron is required for lymphocyte proliferation and macrophage pathogen-killing; deficiency impairs immunity. | Iron & immune cells (opens in a new tab) |
| Loneliness — reduce | Watch this | Moderate | Review / narrative | Loneliness upregulates inflammatory gene expression (CTRA) and downregulates antiviral defence, raising IL-6/CRP. | Social isolation & CTRA (opens in a new tab) |
| Movement (breaking up sitting) | Do this | Moderate | Review / narrative | Meeting activity guidelines (vs sedentary) improves immune function and lowers low-grade inflammation and immunosenescence. | Sedentary time & inflammation (opens in a new tab) |
| Saturated fat | Don't overdo | Moderate | Review / narrative | High saturated-fat intake activates TLR4 signalling and pro-inflammatory pathways. | Saturated fat & inflammation (opens in a new tab) |
| Selenium | Eat enough of | Moderate | Review / narrative | Selenium supports antioxidant defence and T-cell/IFN-y responses; deficiency impairs immunity. | Selenium & immunity (opens in a new tab) |
| Sleep regularity | Watch this | Moderate | Cohort / observational | Irregular/short sleep and circadian disruption raise CRP and impair antibody responses. | Circadian rhythm & immunity (opens in a new tab) |
| Strength (resistance) | Do this | Moderate | RCT / meta-analysis | Resistance training reduces CRP and IL-6 (meta-analysis, 18 RCTs) and counters the sarcopenia-inflammation loop. | Resistance training & CRP (opens in a new tab) |
| Sugary drinks & snacks — cut back | Do this | Moderate | Review / narrative | High sugar intake raises CRP/IL-6 via NF-kB activation and advanced glycation. | Added sugar & inflammation (opens in a new tab) |
| Tobacco / vaping — quit | Do this | Moderate | Review / narrative | Cigarette smoke impairs innate and adaptive immunity and raises inflammatory markers, increasing infection susceptibility. | Smoking & immunity (opens in a new tab) |
| Total Fiber | Eat enough of | Moderate | Review / narrative | Dietary fibre feeds SCFA-producing microbes (butyrate) that lower CRP and regulate mucosal immunity. | Fibre, SCFAs & inflammation (opens in a new tab) |
| Trans fat | Don't overdo | Moderate | Review / narrative | Industrial trans fats raise CRP/IL-6 and endothelial inflammation. | Trans fat & CRP (opens in a new tab) |
| Vitamin A (RAE) | Eat enough of | Moderate | Review / narrative | Vitamin A maintains mucosal/epithelial barriers and NK/T-cell function. | Vitamin A & mucosal immunity (opens in a new tab) |
| Vitamin B12 | Eat enough of | Moderate | Review / narrative | Vitamin B12 supports lymphocyte numbers and NK-cell activity. | B12 & immune cells (opens in a new tab) |
| Vitamin B6 | Eat enough of | Moderate | Review / narrative | Vitamin B6 supports lymphocyte proliferation and Th1 cytokine responses. | Vitamin B6 & immunity (opens in a new tab) |
| Vitamin C | Eat enough of | Moderate | Review / narrative | Vitamin C supports barrier integrity and phagocyte/lymphocyte function; among the strongest-evidence immune micronutrients (shortens common cold). | Vitamin C & immune function (opens in a new tab) |
| Vitamin E | Eat enough of | Moderate | Review / narrative | Vitamin E is a key antioxidant that supports T-cell-mediated immunity, especially with age. | Vitamin E & T-cells (opens in a new tab) |
| Waist-to-height ratio | Watch this | Moderate | Review / narrative | Waist-based adiposity predicts CRP/IL-6 elevation largely independent of BMI. | Central adiposity & CRP (opens in a new tab) |
| Waist-to-hip ratio | Watch this | Moderate | Review / narrative | Higher waist-to-hip ratio marks visceral fat that fuels pro-inflammatory adipokines. | Central adiposity & CRP (opens in a new tab) |
| Zinc | Eat enough of | Moderate | Review / narrative | Zinc is essential for immune-cell development and barrier integrity; deficiency impairs immunity and zinc shortens the common cold. | Zinc & immunity (opens in a new tab) |
| Breath/mind (slow breathing) | Do this | Emerging | RCT / meta-analysis | Meditation and slow-breathing practices reduce CRP and IL-6. | Mind-body breathing & inflammation (opens in a new tab) |
| Flexibility (stretching) | Do this | Emerging | RCT / meta-analysis | Yoga/stretching practice tends to lower IL-6, TNF-a and CRP. | Yoga & inflammatory markers (opens in a new tab) |
| Iron | Don't overdo | Emerging | Review / narrative | Excess iron promotes bacterial growth and oxidative stress ("nutritional immunity"), a risk when over-supplemented. | Iron overload & infection (opens in a new tab) |
| Magnesium | Eat enough of | Emerging | Review / narrative | Magnesium participates in immune activation and inflammation regulation. | Magnesium & inflammation (opens in a new tab) |
| Oral & skin care | Do this | Emerging | RCT / trial | Periodontal/gingival inflammation raises systemic inflammation (CRP); good oral hygiene lowers the immune burden. | Periodontal disease & CRP (opens in a new tab) |
| Sodium | Don't overdo | Emerging | Review / narrative | High salt intake drives pathogenic Th17 differentiation and chronic inflammation. | Salt & Th17 inflammation (opens in a new tab) |
| Supplement discipline | Do this | Emerging | Review / narrative | Correcting genuine micronutrient gaps restores immune function; indiscriminate megadosing does not boost a healthy system. | Micronutrient repletion (opens in a new tab) |
| Total Sugars | Don't overdo | Emerging | Review / narrative | High total-sugar/refined-carb loads promote post-prandial inflammation. | High glycaemic load & inflammation (opens in a new tab) |
| Total Sugars | Don't overdo | Emerging | Systematic review | High total-sugar/refined-carb loads promote post-prandial inflammation. | Association between carbohydrate quality and inflammatory markers: systematic review of observational and interventional studies, Am J Clin Nutr 2014 (opens in a new tab) |
| Toxic relationships — reduce | Watch this | Emerging | Review / narrative | Chronic conflict and hostile relationships elevate inflammatory signalling. | Chronic social stress & IL-6 (opens in a new tab) |
| Zinc | Don't overdo | Emerging | Established clinical | Chronically high zinc impairs immune function and induces copper deficiency. | Excess zinc & immunity (opens in a new tab) |
Held for the whole Immune, Inflammation & Infection system
These rows name no single condition. The Map records them against the whole body system, so they are shown separately rather than folded in.
| Nutrient or lever | Direction | Strength | Evidence type | What was found | Source |
|---|---|---|---|---|---|
| Sleep duration | Watch this | Moderate | Established clinical | Short sleep raises systemic inflammation and lowers infection resistance. | Sleep-restriction and immune literature (opens in a new tab) |
| Carotenoids (provitamin A) | Eat enough of | Emerging | Established clinical | As a provitamin A source, adequate carotenoid intake supports vitamin A status and immune function. | NIH ODS – Vitamin A & Carotenoids (opens in a new tab) |
| Inner circle (close ties) | Watch this | Emerging | Mechanistic | Strong relationships are linked to better immune function and faster recovery from illness. | Social-connection and immune literature (opens in a new tab) |
| Inner circle (close ties) | Watch this | Emerging | Cohort / observational | Strong relationships are linked to better immune function and faster recovery from illness. | Social relationships and physiological determinants of longevity across the human life span, PNAS 2016 (opens in a new tab) |
| Loneliness — reduce | Watch this | Emerging | Mechanistic | Chronic loneliness is linked to higher inflammation and weaker immune function. | Social-connection and immune literature (Harvard Study synthesis) (opens in a new tab) |
| Loneliness — reduce | Watch this | Emerging | Cohort / observational | Chronic loneliness is linked to higher inflammation and weaker immune function. | Social relationships and physiological determinants of longevity across the human life span, PNAS 2016 (opens in a new tab) |
| Tobacco / vaping — quit | Do this | Emerging | Established clinical | Smoking impairs immune defenses and raises risk of pneumonia, tuberculosis and other infections. | US Surgeon General report (opens in a new tab) |