Poor air quality due to pollution is being cited as one of the main causes for an increase in the blood haemoglobin (Hb) levels among young males in the city. A study carried out in the Indian Medical Association’s (IMA) blood bank in Kochi has observed that a significant percentage of walk-in male donors have high haemoglobin levels, something that has been cited as a matter of concern.
The study, which was carried out over a period of one year, has shown that among the 15,000 odd walk-ins, only 11,000 could donate blood, and over 3,600 people had to be deferred from donating blood. Among these deferrals, 52% were temporary deferrals, while 24% constituted men who had high haemoglobin content.
The high haemoglobin was observed in the range 17-19 gm/dL, and that too among the age group of young males aged between 18-40. “What is a cause of concern is the age group, where they are expected to be in prime health condition. Such a high haemoglobin content can be attributed to various reasons. When we notice these high values, we ask them to consult a physician,” says Dr. Rema Menon, medical officer, IMA blood centre.
According to the doctor, the high haemoglobin values are expected among people living in the mountains, as the body would need more red blood cells to carry oxygen, since the amount of breathable oxygen is much lower than at sea level. “It is surprising that it is observed here, where we are living at sea level. And this was also seen in youngsters aged between 18 and 20 years. We believe that this could be a result of external factors such as pollution, a high-protein intake diet, a sedentary lifestyle, and prolonged air conditioner usage,” she says.
Dr. Rema added that this is just a sample size and that more research needs to be carried out. “We need to carry out extensive studies and involve more people to evaluate the situation and address the issues, and overcome the problem,” she said. The study results were based on the data gathered between the period 2024 to 2025.
“One of the reasons for the higher haemoglobin in young men is carbon monoxide exposure from smoking. It can also occur from dehydration, obesity or from habitual exposure to carbon monoxide from other sources such as traffic smoke or biofuels such as wood. Then there are rare medical conditions such as polycythemia vera. The significance of high haemoglobin depends on the clinical context. In a person with no risk factors or symptoms, it is unlikely to be of any clinical significance,” says Dr. Rajeev Jayadevan, convener, Research Cell, Kerala State IMA.
Published – October 11, 2025 09:44 pm IST
