Vanaspati, Reused Oil and Trans Fats: What to Avoid

Quick Answer

Avoid industrially produced trans fats and repeated deep-frying in the same oil. India caps trans fat tightly, but reheated frying oil can still develop harmful breakdown products. Oil used once may be filtered and used for a curry within a day or two, provided it has not deteriorated. Smoke, persistent foam, darkening or thickening mean discard it; their absence does not prove safety.

Why this piece reaches a verdict

The other pieces in this series, tofu versus paneer and ghee versus butter, deliberately declined to name a winner, because the evidence didn’t support one. Trans fats are different. Industrially produced trans fats increase the risk of heart disease, and that’s the reason India’s food regulator, the Food Safety and Standards Authority of India, has progressively capped them. There’s no good-intentions case to be made for them, and no traditional wisdom to balance against. It’s simply a matter of knowing where they come from.

What trans fats are and where they come from

Most industrially produced trans fats come from partial hydrogenation, a process that turns liquid vegetable oil into a more solid, long-lasting fat. That process helped make vanaspati popular for decades: cheaper than ghee, stable at room temperature, and useful for frying, mithai and bakery goods. Today, the formulation and compliance with current limits matter.

Small amounts of trans fats also occur naturally in milk and meat from ruminant animals, such as cows, sheep and goats. These count towards the World Health Organization’s advice to keep total trans-fat intake below 1% of total energy. Industrially produced trans fats should be avoided.

The cooking method matters too. WHO describes the trans-fat increase from high-temperature frying as modest compared with partial hydrogenation. With repeated frying, the concern extends to the wider breakdown of the oil. Even a household that has never bought vanaspati needs to pay attention to the way it fries.

Vanaspati then and now

This is the part many people don’t know, and it changes the conversation. Since 1 January 2022, FSSAI’s standards have capped trans fat in vanaspati, refined oils, bakery shortening, margarine and fat spreads at no more than 2% by weight. Its separate food-products rule limits industrial trans fat to 2 g per 100 g of total oils and fats in foods made with added edible oils or fats. That follows WHO’s recommended national-limit approach: the denominator is the fat, not the whole food.

So the old warning, that vanaspati is loaded with trans fat, needs updating for products made within today’s rules. That isn’t the same as vanaspati being a good everyday choice. Its saturated-fat content still matters. ICMR-NIN’s 2024 dietary guidelines advise avoiding partially hydrogenated fats such as vanaspati as the cooking medium. Favour suitable oils rich in unsaturated fats, in limited amounts.

The risk that hasn’t gone away is reused frying oil

Here’s where an everyday risk still sits. When oil is heated to frying temperature again and again, it breaks down. It may darken and thicken as degradation products build up. Total polar compounds, or TPC, are used to assess that deterioration. FSSAI’s rules say that used vegetable oil or fat with TPC above 25% must not be used. You cannot read that percentage from the colour of a kadhai.

Reusing oil often comes from an entirely sensible wish not to waste something expensive, with the pan topped up rather than emptied. But adding fresh oil does not remove the degraded compounds already there.

Where to stay alert outside the home

The rules have changed the picture for oils and fats, but a few places still deserve a second thought.

• Street and shop-fried snacks. Samosas, pakoras, jalebis, kachoris and bhaturas may be fried in large kadhais used through the day. Ask how the oil is managed and choose food cooked through and served hot. A busy stall may sell snacks quickly without changing its oil; queues and clear-looking oil cannot confirm safe frying practices.
• Bakery goods. Biscuits, puffs, khari and some cakes have traditionally relied on bakery shortening. They are covered by the food-products trans-fat limit, but that does not make them low in saturated fat. Keep them occasional.
• Packaged snacks. Check the ingredients list for ‘partially hydrogenated’ oil and the nutrition panel for trans fat and saturated fat. Words like ‘fried in vegetable oil’ on the front of the packet say nothing about how often that oil was used.

None of this means avoiding fried food outside the house altogether. It means choosing where you buy it with the same care you’d give to anything else you eat.

Reusing oil at home sensibly

FSSAI’s household guidance and ICMR-NIN’s dietary guidelines offer a practical approach:

• Avoid repeated deep-frying in the same oil. There is no universal safe count regardless of temperature, frying time or the food cooked.
• If oil used once has not deteriorated, filter it and use it for a curry. Filtering removes food particles, but it does not reverse degradation. Avoid another round of deep-frying.
• Use it within a day or two. Used oil deteriorates faster than fresh oil. Store it separately rather than pouring it back into the fresh-oil container.
• Discard deteriorated oil. Blue-grey smoke, persistent thick foam, dark or murky oil, or changed consistency are warning signs. Their absence does not prove safety.
• Don’t pour it down the drain. Once cool, mix small amounts with something absorbent, such as sawdust or used paper towels, and bin them according to local rules. For larger amounts, use an authorised used-oil collection service where available.

The habit most worth dropping is the kadhai of oil kept for weeks and topped up before each round of frying. Topping up with fresh oil dilutes the problem without removing it.

Frying for Diwali

Festive frying is a joy and nobody needs to give it up. A few habits make it better:

• Start with fresh oil, treating it as a one-occasion batch rather than something to keep through the season. Discard deteriorated oil even within one session.
• Follow the recipe’s frying temperature and avoid letting the oil smoke.
• Fry in batches rather than crowding the kadhai, which drops the temperature.
• Drain fried food well on a rack or suitable kitchen paper. Let dry snacks cool before storing them in airtight tins; perishable fillings and milk-based foods need appropriate refrigeration.

Different suitable cooking oils have something to offer. Groundnut and mustard oils can both have a place in an Indian kitchen. I suggest a combination across meals, through a commercially prepared blend or by rotation, rather than relying only on sunflower or any single oil. Groundnut, soybean, sunflower and rice bran are examples to consider. Match the oil to the cooking method; variety does not mean using more of it.

When buying fried snacks or mithai, check the shop’s FSSAI licence or registration, handling and storage. These checks cannot establish the condition of its frying oil. The same food-storage principles apply during Diwali as through the year.

Is there a gut angle?

Honestly, a modest one. The strongest reasons to avoid trans fats and heavily degraded oil concern general health rather than your gut specifically. But a heavy, fried meal can leave some people with that uncomfortable, overfull feeling after festive eating. Fatty or greasy foods can trigger indigestion in some people. Fresh oil matters for safety; keeping fried food as the treat rather than the whole meal may help with comfort.

You can also break the old-school habit of assuming a festive dish must be deep-fried. Explore air-frying, shallow-frying, pan-frying, tandoor cooking or baking. These can use less oil; the oil content and nutrients retained depend on the recipe, temperature and time. Enjoying fried foods occasionally is fine, but making them a daily habit can add more energy than you need.

My festive eating advice

The festive season is a time to enjoy, indulge and celebrate with friends and family. It can completely change your routine, food habits and eating pattern. However, it is a temporary phase, and you can get back to your routine once it’s over.

Here are a few tips I would give as a nutritionist to help you enjoy the festival without guilt:

• Enjoy fried foods mindfully and in small portions. Think of them as something to enjoy for the taste, rather than the whole meal.
• Build the rest of the plate too. Choose vegetables, dal or another suitable protein food, and your usual grain or roti, then add smaller portions of fried foods.
• Try a different cooking method. An air-fried version may suit a dish you would normally deep-fry.
• Choose the sweet you enjoy, with its ingredients in mind. A small bowl of milk-based kheer or a sweet made with dates and dry fruits can be an alternative to jalebi. Jaggery-based sweets can fit too, but jaggery is still an added sugar. Dates and dry fruits do not make a sweet automatically low in sugar or calories either. The recipe and portion matter.
• Make festive foods at home when practical. It gives you control over the fat, quantity and cooking method. Use fresh oil and avoid repeated reheating here too.
• Keep water within reach and limit sugary drinks. If fizzy drinks tend to aggravate your symptoms, choose a drink that suits you. Follow any prescribed fluid limit.

If you have cardiovascular disease, diabetes, kidney disease or a digestive condition, follow your individual advice on portions, preparation and food restrictions. Deep-fried foods may need limiting, especially if they worsen symptoms or do not fit your care plan.

If you are following a weight-management plan, mindful portions can help you stay close to your usual energy needs. Enjoy the occasion, then return to your normal meals without guilt.

The honest takeaway

This is the rare fats question with a straight answer. Industrial trans fats are worth avoiding, and India caps them tightly. The habit worth changing is at the kadhai: fry in fresh oil, avoid repeated deep-frying, and only reuse oil for a curry within a day or two if it has not deteriorated. Don’t wait for smoke, foam or darkening before reconsidering an old batch. The Diwali snacks can stay. They’re just made with better oil habits.

Sources

• World Health Organization. Trans fat. 24 January 2024.
• World Health Organization. WHO updates guidelines on fats and carbohydrates. 17 July 2023.
• FSSAI. Food Product Standards, Chapter 2.2: Fats, Oils and Fat Emulsions. Version 2, 5 October 2023; see vanaspati and other regulated fats.
• FSSAI. Food Safety and Standards (Prohibition and Restrictions on Sales) Regulations, 2011. Version XI, April 2025; see definitions, regulation 2.3.14(21) and regulation 2.3.15(8).
• FSSAI. Handling and Disposal of Used Cooking Oil. Guidance Note No. 06/2018.
• ICMR–National Institute of Nutrition. Dietary Guidelines for Indians 2024. Guideline 7, particularly pp. 55–56; guidance on cooking methods, added sugar and overall dietary balance.
• US National Institute of Diabetes and Digestive and Kidney Diseases. Eating, Diet, & Nutrition for Indigestion. Reviewed March 2025.
• NHS. How to cut down on sugar in your diet.

Disclaimer: This article provides general nutrition and food-safety information and is not a substitute for personalised medical advice, diagnosis or treatment. If symptoms continue, are severe, or keep coming back, it’s worth speaking to a doctor. If you have been advised to limit fried food, particular fats, sugar or fluids for a health reason, follow your doctor’s or dietitian’s guidance.