Lychees are an excellent source of important water-soluble vitamins like Vitamin C, vitamin B2 (riboflavin), and minerals like potassium and copper. Nutritionally, ten lychees are equivalent to one orange. Besides, theantioxidant, anti-cancer, anti-microbial, anti-viral, anti-diabetic, and immune-boosting benefits have been known for a long time.
This wonderful fruit with plenty of health benefits had suddenly turned deadly for over 100 children below the age of 10 in Muzaffarpur, Bihar in June 2019. Litchi was blamed for thisacute encephalitis syndrome (AES) outbreak. Acute encephalitis is characterized by acute-onset of fever, mental confusion, seizures, coma and even death. But, was litchi the sole cause for these deaths? Well the answer is “No”. Litchi,perhaps had acted as facilitator for this condition.It has been observed that litchi contains a naturally occurring toxin; Methylene Cyclopropyl Glycine(MCPG)whichhas a tendency to reduce blood glucose levels (a condition known as hypoglycaemia), which becomes compounded in already malnourished individuals. Usually, in a healthy individual, the blood sugar level falls overnight and is generally low in the morning. The body’s natural mechanism brings it back to normal. The glycogen stored in the liver is converted to glucose by a process called glucogenesis. When the glycogen stores are completely exhausted, the stored fatty acids are converted into glucose by a process known as gluconeogenesis. Brain is the largest consumer of glucose with more than 60% of glucose being utilized here. Reduced glucose supply to brain may lead to neural damage.Undernourished or malnourished childrenhave negligible to no glycogen stores in their body. Hence, the conversion of fatty acid to glucose begins, but because of MCGP toxin and insufficiency of glucogenic intermediates,ketone bodies are produced in excess amounts. Brain can use ketone bodies but not for long. As a result, blood glucose levels do not come back to normal, resulting in severe hypoglycemia. Malnourished children who had eaten litchi the prior day and went to sleep with an empty stomach are at highest risk. Healthy and well-nourished children eating litchi do not suffer from AES. It is not definitely known, why older children or adults do not suffer in the same manner.Probably, their glycogen stores are quite sufficient to respond to the litchi dependent hypoglycemia. This condition can be easily treated. Most of the deaths are preventable even in the cases where the blood sugar level has dropped to nil,if treated early with correct administration. A full and complete recovery can be achieved if the affected children are infused with 10% dextrose(glucose) within few hours of the onset of symptoms.Infusing glucose not only restores blood glucose levels, but also halts the excess ketone production. If the infused dextrose is less than 10%, the production of ketone bodies will continue, even if the blood glucose levels are restored. In this case, thebrain cells might not recover and eventually die. Thus, even if the patient survives, he/she may suffer with different extent of brain damage e.g., speech impairment, mental retardation, muscle stiffness etc. In the present context, it would be misleading to say that litchisare not safe for children, but for malnourished ones with significantly low blood glucose levels. There is an urgent need to educate the masses and improve their food habits. Government along with civil society members, NGOs need to take immediate steps to tackle this issue.