The debate on how much edible oil, and what kind of oil, is good or bad for health seems never-ending. But the trick here is finding the right balance as moderation is key, say experts.

Importance of fats in a balanced diet

Meenakshi Bajaj, dietician, Tamil Nadu Government Multi Super Speciality Hospital, said it is essential to understand that all three macronutrients (carbohydrates, fats, and proteins) play a crucial role in an individual’s health. “Fat is an indispensable component of a balanced diet, necessary for the absorption of fat-soluble vitamins, synthesis of hormones, as well as several vital physiological and metabolic functions in the body. Dietary fat comprises both visible and invisible sources. Visible sources include fats and oils, ghee, vanaspati and butter used for cooking. Invisible sources encompass whole eggs, milk and milk products, nuts and oilseeds, meat, poultry, and fish,” she said.

Edible fats and oils have benefits and drawbacks, she said, adding: “There are three types of fatty acids present in our diet: saturated fatty acids (SFA), monounsaturated fatty acids (MUFA), and polyunsaturated fatty acids (PUFA). A healthy diet should incorporate varied sources of fats and oils, maintaining an ideal ratio of healthy fats (mono and polyunsaturated fats) to unhealthy fats (saturated fat).”

Choosing and using oils wisely

Daphnee Lovesley, chief clinical dietitian, Apollo Hospitals, Chennai, points out, “Oils are essential in our diet as they provide essential fatty acids that the body cannot produce. Like everything else, moderation is key. Oils are calorie-dense, providing about 9 calories per milliliter, and in Indian cooking, there is often a tendency to use them generously, particularly in fried foods. Reducing oil intake by four to five teaspoons per person per day can make a big difference. Nuts like almonds, walnuts, or peanuts can be enjoyed in moderation—a handful a day is sufficient.”

The National Institute of Nutrition (NIN) suggests incorporating a diverse variety of oil seeds, nuts, and whole grains, Ms. Bajaj pointed out. “Studies indicate that consuming nuts like almonds and cashews can improve lipid profiles and reduce blood pressure in individuals with type 2 diabetes. However, moderation is key,” she said.

Blending oils to achieve a balance of fatty acids and antioxidants is beneficial, she said, noting: “NIN advises combining oils such as groundnut, sesame, rice bran, and mustard oils, which have been shown to reduce the risk of type 2 diabetes and metabolic syndrome.”

Health risks associated with reheated oils and trans fat

Ms. Lovesley further adds. “Oils rich in monounsaturated fats—such as sesame oil, groundnut oil, and rice bran oil—are good options and are readily available locally. Using a blend of oils is often considered a safer and more balanced approach.”

However, reusing oil is harmful, she adds. “Repeated heating at high temperatures causes chemical changes that lead to the formation of polycyclic aromatic hydrocarbons, which are carcinogenic. Reheated oils have been linked to an increased risk of cancer, cardiovascular diseases, and elevated cholesterol and blood pressure levels. When consuming food outside, it is difficult to know how many times the oil has been reheated—this could contribute to inflammation and, subsequently, obesity.”

Ms. Bajaj emphaised that trans fats from reheated oil, bakery items (such as cakes, pizza, puffs, pastries, biscuits, cookies, doughnuts), and partially hydrogenated edible fats in packaged and processed snacks increase triglycerides and LDL cholesterol (bad cholesterol), lower HDL cholesterol (good cholesterol), and heighten the risk of cancers and cardiovascular diseases. Check food labels on ready-to-eat foods for partially hydrogenated fats (unhealthy fats), she added .

The impact of cooking methods on the nutritional quality of oils should be considered. “Oils exposed to high temperatures for extended periods can lose antioxidants and generate toxic compounds and trans fats. Repeated heating of cooking oils produces harmful compounds and should be avoided. On a household level, vegetable oil once used for frying should be filtered and reused for sautéing purposes within the next 24 hours. Remove food particles from oil during frying before they turn black. Oils repeatedly heated should not be mixed with fresh oil but can be used for seasoning,” she said.

Healthy eating as preventive care

With obesity being a major public health concern, it’s important to recognise the key contributing factors: poor dietary habits, a sedentary lifestyle, and inadequate sleep. Stress can also play a role in some individuals. “However, we should focus on what we can control—eating balanced meals, staying physically active, and maintaining good sleep hygiene—to prevent obesity. Childhood obesity is growing too, making it crucial to encourage healthy habits early in life,” Ms. Lovesley said.

Ms. Bajaj reiterates that intake of oils and fats should be moderated. “It’s not about restriction; it’s about smart and healthy choices for improved metabolic health. By making informed choices regarding the types and quantities of fats in our diets, we can promote better health and well-being for ourselves and our families,” she said.

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Tamil Nadu has banned the manufacture, storage and sale of mayonnaise prepared from raw eggs for a period of one year with effect from April 8. The ban, issued in the interest of public health, is on the basis that mayonnaise made of raw eggs is a “high risk food”, carrying a risk of food poisoning.

According to a notification issued in the Government Gazette by Principal Secretary and Commissioner of Food Safety R. Lalvena, any activities related to any stage of manufacture, processing, packaging, storage, transportation, distribution, food services, catering services and sale of mayonnaise prepared from raw egg is prohibited in the State under section 30 (2) (a) of Food Safety and Standards Act, 2006 and order of the Commissioner of Food Safety of Tamil Nadu.

Mayonnaise is a semi-solid emulsion generally composed of egg yolk, vegetable oil, vinegar and other seasonings served along with food items such as shawarma. Mayonnaise made of raw eggs is a high-risk food as it carries a risk of food poisoning especially from Salmonella bacteria, Salmonella typhimurium, Salmonella enteritidis, Escherichia coli and Listeria Monocytogenes, the notification said.

It has come to notice that a number of food business operators use raw egg for preparation of mayonnaise, improper storage facilitates contamination by microorganisms that creates a public health risk particularly by Salmonella typhimurium, Salmonella enteritidis, Escherichia coli and Listeria Monocytogenes, it said.

In any specific circumstances, on the basis of assessment of available information and if the possibility of harmful effects on health is identified but scientific uncertainty persists, provisional risk management measures to ensure that health is protected can be adopted as per the Act, pending further scientific information for a more comprehensive risk assessment.

The notification said that no food business operator should manufacture, store, sell or distribute any food which for the time being is prohibited by the Food Authority or the Central Government or State government in the interest of public health.

The test kits have been developed under the Department of Biotechnology’s (DBT) partnership programme Grand Challenges India (GCI) at the Biotechnology Industry Research Assistance Council (BIRAC).
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Indigenously developed (Human papillomavirus) HPV test kits for cervical cancer screening were launched on Wednesday (April 23, 2025).

The test kits have been developed under the Department of Biotechnology’s (DBT) partnership programme Grand Challenges India (GCI) at the Biotechnology Industry Research Assistance Council (BIRAC).

The DBT supported research coordinated by the All India Institute of Medical Sciences (AIIMS) Delhi, with testing done at laboratories at AIIMS, National Institute of Cancer Prevention and Research (NICPR), Noida; and the National Institute for Research in Reproductive and Child Health (NIRRCH), Mumbai, in collaboration with World Health Organisation (WHO) International Agency for Research on Cancer (IARC).

“The key feature of these kits is the inclusion of only the seven-eight most common cancer-causing types that will allow a very efficient and cost-effective screening programme which will be most suitable for India,” Dr Neerja Bhatla, former head of the department of Obstetrics and Gynaecology at AIIMS, Delhi and chief coordinator of the programme said.

The study titled ‘Validation of Indigenous Human Papillomavirus Tests for Cervical Cancer Screening in India (i-HPV)’ validated indigenously developed, rapid, point-of-care, RTPCR-based HPV diagnostic test kits for screening cervical cancer in premier research and development laboratories of India.

“Given the enhancement of RTPCR-based diagnostic facilities across the nation in the post-COVID era, the introduction of sensitive RTPCR-based HPV testing kits might prove to be cost effective screening method over classical HPV DNA and Pap smear for deployment in the national cancer screening programme,” Dr Bhatla said.

Cancer of the uterine cervix is the second most common cancer among Indian women. According to WHO data, one out of every five women in the world suffering from the disease is an Indian, Dr Bhatla stated.

Besides the high incidence of cervical cancer owing to its late diagnosis and with consequent poor survival, 25% of global mortality due to cervical cancer occurs in India, she said.

Thus, there has been a pressing need for the development of control strategies for the prevention and screening of cervical cancer. The currently available methods of screening of cervical cancer include Visual Inspection with Acetic Acid (VIA), Papanicolaou test (Pap test or Pap smear) and HPV DNA testing, she stated.

Regular population screening by Pap smears has been successfully implemented in the developed world. Nevertheless, it is costly, resource-intensive and only moderately sensitive. VIA screening requires considerable training and re-training for quality assurance and has high false positivity rates with programmatic challenges, she said.

HPV testing has the best diagnostic accuracy if it conforms to international standards of validation. As part of the Global Declaration for Cervical Cancer Elimination, WHO recommends a transition to HPV testing in all countries, whereby only two tests in a lifetime, at age 35 and again by age 45 years, will be sufficient. The target is to set up processes to screen 70% of eligible women by 2030, Dr. Bhatla stated.