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Understanding RDW in Blood Test: A Comprehensive Guide
Blood Test
Mon Nov 06 2023
When you undergo a routine blood test you may come across various abbreviations and terms which can be confusing at times. One such term is RDW which stands for Red Blood Cell Distribution Width. RDW is an important parameter measured during a complete blood count (CBC) test. Let's dive into the meaning of RDW, its significance, and what abnormal results can indicate.
What is RDW?
RDW refers to the variation in the size of red blood cells (RBCs) in a blood sample. It measures the difference in volume of individual RBCs and provides insights into the distribution or heterogeneity of cell sizes. The RDW value is presented as a percentage reflecting the width of the histogram curve of RBC volume.
Significance of RDW:
The RDW value is primarily used to evaluate and diagnose various types of anemia. Anemia is a condition where the body lacks sufficient healthy red blood cells to carry an adequate amount of oxygen to the tissues. RDW helps in differentiating between different types of anemia.
1. Iron Deficiency Anemia: This is the most common type of anemia and is associated with a high RDW value. In this condition, the body lacks sufficient iron to produce healthy red blood cells leading to a wide variation in the size (anisocytosis) of RBCs.
2. Vitamin B12 Deficiency Anemia: This type of anemia is caused by a deficiency in vitamin B12 which is essential for the production of healthy red blood cells. It is characterized by macrocytic (larger than normal) RBCs and an elevated RDW.
3. Folate Deficiency Anemia: Similar to vitamin B12 deficiency anemia this condition is caused by a deficiency in folic acid. Like B12 deficiency it leads to macrocytic RBCs and an increased RDW.
4. Hemolytic Anemia: Hemolytic anemia is a condition where the breakdown of red blood cells exceeds their production. In this condition, the RDW value may be elevated due to the presence of both smaller RBCs (microcytic) and larger RBCs (macrocytic).
5. Blood Loss: If there is acute or chronic blood loss the body produces new RBCs rapidly. This can result in a wide range of RBC sizes and an increased RDW value.
Interpreting Abnormal RDW Results:
RDW value outside the normal range may indicate an underlying health condition and should be further investigated by a healthcare professional. A high RDW value suggests a varied range of RBC sizes while a low RDW value indicates a more uniform distribution.
It is essential to consider RDW in combination with other CBC parameters to determine the underlying cause accurately. Your healthcare provider will assess your complete blood count results and consider your medical history symptoms and additional tests if required.
RDW is an important parameter measured during a complete blood count test and provides valuable information about the variation in red blood cell sizes. It aids in the diagnosis and differentiation of various types of anemia. If you receive abnormal RDW results it is essential to consult a healthcare professional who will interpret the findings in the context of your overall health and additional diagnostic tests if necessary. Remember timely detection and treatment of anemia can help improve your overall well-being.
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HbA1c Blood Test for Long-Term Diabetes Control
Managing diabetes is not just about keeping track of daily blood sugar readings it is about maintaining long-term stability. One of the most trusted tools for this purpose is the HbA1c blood test, often referred to as the “three-month average test”. it reveals how well your blood sugar has been managed over the past 8 to 12 weeks. For anyone living with diabetes, this test plays a vital role in monitoring health and preventing future complications.
What is the HbA1c Test?
Hemoglobin A1c (HbA1c) is a simple blood test that measures the percentage of hemoglobin, the protein in red blood cells that carries oxygen, coated with sugar (glucose). When glucose circulates in your blood, it naturally attaches to hemoglobin. The higher your blood sugar levels, the more glucose sticks to the hemoglobin. Since red blood cells live for about three months, the HbA1c test gives an average picture of your blood sugar levels over that period, unlike daily finger-prick tests, which show only current levels.
Why is it Important?
The HbA1c test is essential for both diagnosing diabetes and monitoring its control.
- A normal HbA1c level is usually below 5.7%.
- Levels between 5.7% and 6.4% may indicate prediabetes,
- Levels of 6.5% or higher suggest diabetes.
For people already diagnosed, doctors often recommend keeping HbA1c below 7% to reduce the risk of complications.
Unlike random blood sugar checks that fluctuate depending on meals, stress, or activity, HbA1c provides a clearer and more reliable picture of overall control. This helps doctors adjust medications, lifestyle plans, and treatment strategies more effectively.
Benefits of the HbA1c Test
- Long-Term Insight – Instead of worrying about one or two high readings, the HbA1c test shows your overall pattern.
- Convenient – No fasting is required. You can take this test at any time of the day.
- Early Warning System – Consistently high HbA1c levels warn of poor control, which could lead to complications such as kidney damage, heart disease, eye problems, or nerve issues.
- Motivation for Lifestyle Changes – Seeing your HbA1c improve can be highly motivating, encouraging healthier food choices, regular exercise, and proper medication use.
How Often Should You Take the Test?
For people with diabetes, doctors usually recommend taking the HbA1c test at least twice a year. However, if treatment is being adjusted or blood sugar levels are unstable, the test may be advised every three months. For individuals at risk of diabetes, routine testing can help detect the condition early and prevent it from progressing.
Improving Your HbA1c Levels
Lowering HbA1c is possible with consistent effort. Here are some effective strategies:
- Balanced Diet – Include more whole grains, vegetables, lean proteins, and fiber-rich foods while limiting refined sugars and processed snacks.
- Regular Exercise – Aim for at least 30 minutes of physical activity most days of the week.
- Medication Adherence – Take diabetes medicines or insulin as prescribed by your doctor.
- Stress Management – Stress can raise blood sugar, so relaxation techniques such as yoga, meditation, or deep breathing can help.
- Regular Monitoring – Combine home blood sugar checks with HbA1c testing to stay on track.
The HbA1c test is more than just a number; it serves as a health compass that guides people living with diabetes toward long-term control and better quality of life. By offering a reliable picture of how well blood sugar has been managed over months, it empowers individuals and doctors to take timely action. Regular HbA1c testing, along with a healthy lifestyle and proper treatment, is the key to reducing complications and living well with diabetes.
At Manipal TRUtest, we offer comprehensive diabetes testing packages, including HbA1c test, to help you stay on top of your health. Early monitoring leads to better outcomes—schedule your test today.

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Know the Reason Behind Your Fever with a Blood Test
Fever is one of the most common symptoms experienced by people of all ages. It is not a disease but a warning sign that the body is fighting an infection or responding to an underlying health issue. While occasional, mild fevers often resolve on their own, persistent or high-grade fever should never be ignored. Understanding the root cause of fever is crucial , and this is where a blood test plays a vital role.
Why Fever Occurs
Fever occurs when the body’s temperature rises above the normal range, usually in response to an infection. This rise in temperature is the immune system’s way of creating an environment less favourable for bacteria or viruses to survive. Common causes of fever include –
- viral infections (such as flu or dengue),
- bacterial infections (such as typhoid or urinary tract infections),
- parasitic diseases (such as malaria), and
- inflammatory or autoimmune conditions.
- side effects of medication or a sign of more serious illnesses.
The Role of Blood Tests in Identifying the Cause
When a fever lasts more than a couple of days, or when its origin is unclear, a blood test becomes an important diagnostic tool. It helps doctors pinpoint the underlying cause, differentiate between bacterial and viral infections, and assess the severity of the illness.
Some common blood tests for fever diagnosis include:
- Complete Blood Count (CBC) – Evaluates the levels of red and white blood cells, helping detect infections, anaemia, or blood disorders.
- Blood Culture – Identifies bacteria or fungi in the blood, guiding doctors in selecting the right antibiotics.
- Malaria Parasite Test – Detects the presence of malaria-causing parasites.
- Dengue NS1 Antigen and Antibody Tests – Confirms dengue fever and determines its stage.
- Typhoid Tests (Widal or TyphiDot) – Diagnose typhoid fever caused by Salmonella bacteria.
- ESR and CRP Tests – Measure inflammation levels in the body, useful for detecting infections or autoimmune conditions.
Benefits of Early Diagnosis
Timely blood testing not only helps confirm the cause of fever but also ensures that the right treatment is started without delay. This prevents complications, reduces the duration of illness, and avoids unnecessary use of antibiotics in cases where they are not required. For example, if a blood test confirms a viral infection, supportive care may be sufficient; but if it points to a bacterial infection, the correct antibiotics can be prescribed immediately.
When to Seek Medical Help
You should consult a doctor and consider a blood test if your fever is high-grade (above 102°F), lasts for more than 3 days, is accompanied by severe symptoms like rash, persistent vomiting, breathing difficulties, chest pain, confusion, or if it occurs in infants, elderly individuals, or people with weakened immunity.
A fever should never be dismissed as “just a common symptom.” It is your body’s way of asking for attention. Blood tests are the most reliable way to uncover the real cause, enabling your doctor to provide the most effective treatment.
At Manipal TRUtest, we provide comprehensive fever panels with accurate results, doorstep sample collection, and NABL-accredited labs — helping you recover faster with the right care.
Don’t let an unexplained fever go unchecked. Book your Fever Blood Test Package with Manipal TRUtest today and take charge of your health.

Blood Test
Cholesterol Levels and What a Lipid Test Reveals
Cholesterol is a waxy, fat-like substance found in every cell of the human body. While it is essential for producing hormones, vitamin D, and substances that aid digestion, an excess of cholesterol in the bloodstream can pose serious health risks. Understanding your cholesterol levels through a lipid test is a crucial step in preventing heart disease, stroke, and other cardiovascular issues.
What Is Cholesterol?
Cholesterol is categorized into two main types: Low-Density Lipoprotein (LDL), often referred to as "bad" cholesterol, and High-Density Lipoprotein (HDL), known as "good" cholesterol. LDL carries cholesterol to your arteries, where it can build up and form plaques, narrowing the arteries and increasing the risk of heart attack and stroke. HDL, on the other hand, helps remove cholesterol from the bloodstream, transporting it back to the liver for excretion.
Another important component is Triglycerides, which are a type of fat found in your blood. When you eat more calories than your body needs, especially from sugar and fat, the excess is converted into triglycerides. High triglyceride levels, along with elevated LDL and low HDL, are linked to an increased risk of cardiovascular disease.
What Is a Lipid Test?
A lipid test, also known as a lipid profile or lipid panel, is a simple blood test that measures the levels of different fats in your blood. Typically, the test includes:
- Total Cholesterol: The overall amount of cholesterol in your blood.
- LDL Cholesterol: Often labelled as “bad” cholesterol because high levels can lead to plaque buildup.
- HDL Cholesterol: Known as “good” cholesterol as it helps remove LDL from the arteries.
- Triglycerides: Elevated levels can raise your risk of heart disease and may indicate metabolic syndrome or diabetes.
The test is usually performed after fasting for 9 to 12 hours, as food intake can temporarily influence lipid levels. Based on the results, your healthcare provider can assess your risk of cardiovascular disease and suggest lifestyle changes or medications if necessary.
Interpreting the Results
Normal lipid levels are typically defined as:
- Total Cholesterol: Less than 200 mg/dL
- LDL Cholesterol: Less than 100 mg/dL
- HDL Cholesterol: 60 mg/dL or higher (considered protective)
- Triglycerides: Less than 150 mg/dL
Borderline or high readings may signal the need for dietary adjustments, increased physical activity, weight management, or in some cases, medication like statins.
Importance of Regular Testing
Regular lipid testing is especially important for individuals over 40, those with a family history of heart disease, people with diabetes, obesity, or a sedentary lifestyle. Early detection of abnormal cholesterol levels can help you take proactive measures to protect your heart and overall health.
Monitoring cholesterol levels through a lipid profile test is a simple yet powerful tool in maintaining cardiovascular health. It offers valuable insights into your risk profile and can guide lifestyle modifications or medical interventions. By keeping cholesterol levels in check, you can significantly reduce your risk of heart disease and lead a healthier, longer life. Regular screening, a balanced diet, regular exercise, and stress management are key to keeping your heart strong and your cholesterol within a healthy range.
Take control of your heart health - test early, stay healthy.