BENGALURU: A study conducted across five cities to ascertain their cholesterol burden has found that Bengaluru is low on ‘good’ cholesterol (high-density lipoprotein).Bengaluru reported lesser than optimal levels of HDL cholesterol — 9/10 — which means only one of the 10 people tested had desirable levels. Chennai, Mumbai, Delhi and Pune reported 8/10.The study conducted by RV Metropolis, a chain of diagnostic labs, examined over 5 lakh samples during 2017-19 and looked into cholesterol as a major cause of cardiac ailments.Cholesterol is a waxy, fat-like substance found in every cell of the body. Total cholesterol means the total amount of cholesterol in the blood, which includes low-density lipoprotein (LDL or bad cholesterol) and HDL.In terms of LDL, Bengaluru scored 6/10 — six of 10 people reported high or borderline high levels. While Mumbai, Delhi and Pune scored 5/10, Chennai fared the best with 3/10, meaning 7 of 10 people had optimal levels of LDL cholesterol.As per the standards followed, total cholesterol levels within 200 mg/dl are considered desirable, between 200 and 239 mg/dl borderline and above 240 mg/dl high.High cholesterol levels in the blood lead to a build-up in the walls of arteries causing arthrosclerosis, a form of heart disease. This results in narrowing of arteries, due to which not enough oxygen and blood is carried to the heart, which may cause chest pain. When blood supply to the heart is completely cut off, it leads to a heart attack.Dr Ravi Kumaar, chief pathologist, RV Metropolis, Bengaluru, said: “Being unaware of cholesterol levels could lead to complications that could worsen without intervention. Lowering high cholesterol levels lessens the risk of developing heart diseases.”However, the survey mentions no reason for Bengaluru faring the worst. Dr Anita Suryanarayan, vice-president, operations, South India, Metropolis Healthcare Ltd, said: “What causes high cholesterol levels needs to be further studied. But as per our observation, eating out or late at night, working late hours and high pollution levels are some factors. Dietary patterns impact cholesterol levels.”Dr Rahul Patil, cardiologist and head of PCAD (Premature Coronary Artery Disease) division at Sri Jayadeva Institute of Cardiovascular Sciences (SJICS) , said low HDL is a part of a wider syndrome called metabolic syndrome, which is more common in the southeast Asian population, mainly Indians.“The ultimate cause of metabolic syndrome is insulin resistance, where body receptors show decreased response to insulin in spite of normal levels. This could worsen with obesity, sedentary lifestyle and a high calorie diet with refined carbohydrates and more fat,” he said.