Red cell distribution width (RDW) measures the variation in red blood cell size, expressed as a percentage (%). Uniform cell size supports efficient oxygen transport and stable energy production, while higher RDW can signal nutrient or metabolic imbalances.
Tracking RDW helps you spot early changes in cellular health and resilience. Keeping levels within the optimal 11.5–14.5% range supports consistent energy, recovery, and long-term wellbeing.
Red cell distribution width (RDW) is available in Vively's Metabolic Essentials Test. Book your blood test now for only $199 per test.
RDW is a laboratory metric that quantifies how much variation there is in the sizes of your red blood cells, expressed as a percentage. It is calculated as the coefficient of variation of red blood cell volume. A lower RDW means your red blood cells are more uniform in size, whereas a higher RDW shows greater heterogeneity.
Why does it matter for long-term health and wellbeing?
While RDW historically has been used to help diagnose types of anaemia, more recent research shows that higher RDW values — even within “normal” laboratory limits — are independently associated with poorer long-term outcomes in population studies.
Because RDW can reflect nutrient status, inflammation or oxidative stress, it offers a broad lens into changes in your system before they manifest more overtly. For someone pursuing optimal energy, metabolic health and longevity, RDW is an early warning gauge — giving you chance to act, refine and optimise your internal milieu.
What’s an optimal level of RDW?
* These ranges reflect typical Australian lab units (percentage). Your lab may report slightly different cut-offs, so always check the reference they provide.
What influences RDW levels?
Several lifestyle and internal factors may drive RDW shifts, including:
Nutrient status (particularly iron, vitamin B12, folate)
Low-grade chronic inflammation or oxidative stress
Red blood cell turnover or production dynamics
Subtle metabolic dysfunction or stress burden
Hydration, hormonal fluctuations or metabolic shifts
Because RDW is integrative, changes may reflect a combination of influences rather than a single cause.
What does it mean if RDW is outside the optimal range?
A value above the optimal band (but still within lab “normal”) suggests increased heterogeneity in red blood cell size. In practical terms, that might indicate your body is under mild stress — for example, a nutrient mismatch, subtle inflammation or oxidative strain — that could, over time, erode metabolic resilience or energy capacity. A value below the optimal band (rare) could suggest overly uniform red cell size, which in some rare instances might warrant review of bone marrow or nutritional factors. Either way, the signal is an opportunity to explore contributing lifestyle or nutritional inputs, rather than a diagnosis.
How can I support healthy RDW levels?
Supporting RDW means nurturing red blood cell health and reducing systemic stress. Practical steps include:
Optimising intake of key nutrients (iron, B-vitamins, folate) via diet or guided supplementation
Focusing on anti-inflammatory eating patterns and antioxidants
Ensuring good sleep, stress resilience and physical activity
Minimising exposure to oxidative burden (e.g. tobacco, excess environmental toxins)
Monitoring hydration, hormone balance and metabolic markers
Periodic retesting to observe trends and guide incremental adjustments
This information is provided for general health and wellness purposes only and does not replace medical advice.
References
Skjelbakken, T., et al. (2014). Red cell distribution width is associated with incident myocardial infarction in a general population: The Tromsø Study. Journal of the American Heart Association.
Fava, C., et al. (2019). The role of red blood cell distribution width (RDW) in risk stratification. Annals of Translational Medicine.
Ichinose, J., et al. (2016). Prognostic significance of red cell distribution width in elderly patients. Journal of Thoracic Disease.
Wang, N. J., et al. (2023). The association between red cell distribution width and mortality. PMC.
The blood test includes a breakdown of over 50 blood markers across hormones, heart, metabolism, liver and blood health, and also includes your Biological Age, which is a researched-backed analysis of your biological rate of aging, and indication of how well your body is aging. You will also receive personalised recommendations across nutrition, movement, sleep, stress and mindset, as well as resources to learn and develop knowledge in your body and health.
Vively includes 3x more lab tests than most GP check-ups, giving you a much more in-depth understanding of your health and wellbeing. Vively also tracks your results over time and brings you actionable insights based on your specific results. All lab tests come with a personalised protocol and action plan to improve your weight and long-term health.
The Vively membership contains everything you need to achieve your health goals:
- Access to your custom health protocol in the Vively app - Access to our support team at any time during business hours - Tools to help you build long-term habits & track health improvements - Access to Continuous Glucose Monitors to optimise your blood sugar levels - Book in follow up blood tests whenever you need
We test over 50 biomarkers across your blood, hormones, metabolism, liver, kidneys, cholesterol, and more. Each one tells us something important about your health. By looking at them together, we can understand the relationship between your weight and your health — and create a plan that’s personalised to you.
Each one was carefully chosen because it helps us answer one or more of these questions: Is your body handling food and energy in a healthy way? Are there hidden factors you wouldn’t know about otherwise? What plan is right for you, and how can we track progress?
At Vively we take our data security very seriously. All of your data is 256 bit SSL/TLS encrypted. Access to your medical records are encrypted with the industry standard AES-256 encryption algorithm to protect your data at all times. You can read more about this in our privacy policy.Only our health professionals and authorised staff will have access to view your medical records. Data can be stored on third party servers, but it’s always encrypted.
Vively is a general wellness platform and does not provide medical advice, diagnosis, or treatment. Any information, insights or guidance offered through our app, website, programs, or coaches is for educational and informational purposes only and should not be considered a substitute for professional medical advice or care. Always consult a qualified healthcare provider before making any health-related decisions.
We acknowledge the Traditional Custodians of the lands where we live and work, the Gadigal of the Eora Nation. We pay our respects to their Elders past and present.
.png)
