Hemoglobin is a protein rich in iron located inside red blood cells. Its primary job is to transport oxygen from the lungs to all the tissues and organs throughout the body. This protein is also what gives blood its characteristic red color. The level of hemoglobin is a common measurement analyzed during a complete blood count (CBC), a routine blood test that provides a snapshot of your overall health.
This value represents the amount of hemoglobin in a given volume of blood, measured in grams per deciliter (g/dL). Understanding where this number falls within established reference ranges is the first step in interpreting the result.
Understanding Hemoglobin Levels
Hemoglobin reference ranges differ primarily by sex. For most adult men, a normal hemoglobin level is between approximately 13.2 and 17.5 g/dL. For adult women who are not pregnant, the range is between 12.0 and 15.5 g/dL.
Based on these common ranges, a result of 16.2 g/dL would be considered within the normal spectrum for an adult male. However, for an adult female, this same result would be classified as elevated or high. It is also important to recognize that these reference ranges can have slight variations from one laboratory to another.
Normal hemoglobin values are different for other populations. For instance, infants typically have higher levels at birth, which gradually decrease over the first few months of life. Values also change during pregnancy to support the developing fetus.
Potential Causes of Elevated Hemoglobin
An elevated hemoglobin level indicates a higher-than-normal concentration of this protein in the blood. Some factors are related to lifestyle and environment. For example, dehydration does not increase the number of red blood cells, but it does decrease the volume of plasma, making the blood more concentrated and artificially raising the hemoglobin measurement.
Living at a high altitude is another common cause. In environments with lower oxygen levels, the body compensates by producing more red blood cells to enhance its oxygen-carrying capacity. Smoking can also lead to elevated levels, as the carbon monoxide from cigarette smoke reduces hemoglobin’s ability to carry oxygen, signaling the body to produce more red blood cells.
In some cases, a high reading points toward erythrocytosis, a condition of increased red blood cell mass. One type is secondary polycythemia, where an illness like chronic lung disease or certain kidney tumors causes the body to produce excess erythropoietin, a hormone that stimulates red blood cell production. A rarer cause is polycythemia vera, a bone marrow disorder where the marrow produces too many red blood cells without the proper hormonal signal.
Associated Symptoms and When to Consult a Doctor
A hemoglobin level of 16.2 g/dL might not cause any noticeable effects, but persistently high levels can be associated with a range of symptoms:
- Headaches or dizziness
- Unusual sweating or fatigue
- Shortness of breath
- A feeling of fullness in the abdomen
- A reddish, ruddy complexion
Many people with a mildly elevated hemoglobin level have no symptoms, with the finding often discovered incidentally on a routine blood test. The presence or absence of symptoms does not necessarily correlate with the severity of the underlying cause.
Discussing your results with a healthcare provider is the most appropriate next step. They can evaluate the 16.2 g/dL value in the context of your complete health profile, medical history, and other lab results to determine its significance and decide if further investigation is needed.