Why Is Mustard Oil Banned in USA? Erucic Acid, Canola Oil & Best Cooking Oil for India

Walk into any Indian kitchen in North India, West Bengal or Bihar and you will almost certainly find a bottle of sarson ka tel sitting near the stove. It has been used for cooking, pickling and even massages for thousands of years. But go to any Indian grocery store in the United States and you will find the same oil sitting on the shelf with three words on the label: For external use only.

That label is not a marketing choice. It is a legal requirement. The US FDA has banned mustard oil for cooking and eating. Yet in India, millions of families use it every single day without any restriction.

So what is actually going on here? Why did America ban something India has been eating for 5000 years? And how did this same controversy lead to the invention of canola oil, which is now one of the world's most sold cooking oils? And more practically, which cooking oil should you actually be using at home, especially if you have diabetes? This blog goes through all of it in plain language.

Why Is Mustard Oil Banned in the USA for Cooking?

Mustard oil is banned in the USA because it contains 20 to 40 percent erucic acid, a type of fatty acid that caused serious heart damage in animal studies. In the 1970s scientists fed high doses of erucic acid to rats and found it deposited as fat in the heart muscle tissue, a condition called myocardial lipidosis. The hearts of the test animals weakened and the animals died. Based on these findings the US FDA issued Import Alert 26-04 prohibiting mustard oil from being sold for cooking or eating.

The FDA's exact statement was that expressed mustard oil may contain 20 to 40 percent erucic acid, which has been shown to cause nutritional deficiencies and cardiac lesions in test animals. Any mustard oil sold in the US must be labelled for external use only. The only exception is a specially bred variety with erucic acid below 2 percent, which is the same principle behind how canola oil was invented.

The important thing to understand here is that no large-scale human study has definitively proven that normal cooking amounts of mustard oil cause the same heart damage in people. The 1970s animal studies used very high doses fed consistently over a long period. Human metabolism is considerably more complex than that of rats or mice, and Indian scientists argue the human liver processes erucic acid through a pathway called beta-oxidation before it can accumulate in heart tissue.

The EU, Australia and New Zealand took a middle ground approach. Instead of banning mustard oil outright, they set consumption limits. India's FSSAI has approved mustard oil freely for cooking with no restrictions, relying on the traditional usage evidence and the lack of conclusive human data showing harm.

What Is Erucic Acid and Why Does Mustard Oil Have So Much of It?

Erucic acid is a monounsaturated fatty acid with a 22-carbon chain. It belongs to the omega-9 family and is found primarily in seeds of Brassica plants, which include mustard, rapeseed, cabbage and kale. In mustard oil specifically, erucic acid makes up 20 to 40 percent of the total fatty acid content, which is far higher than any other commonly consumed cooking oil.

The mustard plant produces erucic acid intentionally. It serves two purposes. First, it acts as a dense long-term energy reserve in the seed, giving the seed enough stored energy to survive dormant for a long time and then germinate when conditions are right. The 22-carbon chain stores a lot of chemical energy that releases slowly. Second, the mustard seed has another separate defense compound called sinigrin.

When a seed is broken or crushed, sinigrin comes into contact with a separate enzyme in the seed and converts immediately into allyl isothiocyanate. This is the sharp burning compound that shoots into the nose and eyes of any insect, bird or rodent trying to eat the seed. It causes immediate discomfort and drives the predator away. This is also exactly why mustard oil has that distinctive pungent smell and why it stings your nose when you heat it. The same compound is what makes wasabi and horseradish burn.

In terms of the human body, erucic acid presents a challenge because of its long chain length. Most fatty acids in food have 16 to 18 carbon atoms. The 22-carbon erucic acid takes longer to metabolize. In simple organisms like insects or in the simpler digestive systems of small rodents, erucic acid is not broken down efficiently and accumulates in fatty tissues. Whether human metabolism breaks it down fast enough to prevent accumulation in heart tissue is the scientific question that remains incompletely answered.

What Is Canola Oil and How Was It Invented From Mustard?

Canola oil was developed in Canada in the early 1970s by selectively breeding rapeseed, which is a close relative of mustard, to contain less than 2 percent erucic acid instead of the original 30 to 40 percent. The name CANOLA stands for Canadian Oil Low Acid. The Canadian government approved it for food use and Canadian farmers began exporting it globally, where it became the fourth most sold cooking oil in the world.

The backstory is interesting. In the 1960s and 1970s, American scientists were pushing everyone to move away from animal fats like lard and butter toward vegetable oils, claiming saturated fats caused heart disease. Canada needed a vegetable oil to compete in this growing market. Regular rapeseed oil was not accepted in Western countries because of its high erucic acid content and its strong smell, similar to mustard oil.

Scientists at the University of Manitoba spent years cross-breeding rapeseed varieties until they produced a plant whose seeds naturally had almost no erucic acid. They also eliminated most of the glucosinolates that cause the strong smell. The result was a neutral-smelling, low-erucic oil that the Canadian government approved as safe. The growers trademarked the name canola to clearly separate it from the problematic reputation of regular rapeseed oil.

What this means is that canola oil is essentially a genetically improved version of mustard oil. It has the same basic fatty acid profile as mustard oil in terms of SFA and MUFA content, around 70 percent combined, but without the erucic acid. The trade-off is that it has almost no flavour and a significantly lower smoke point of about 200 degrees Celsius compared to mustard oil's 250 degrees.

Mustard Oil vs Canola Oil: Side by Side Comparison

The smoke point difference is worth paying attention to. Indian cooking regularly involves high-heat methods like deep frying, strong tadkas and long sauteing. Mustard oil handles 250 degrees Celsius, which is higher than any other commonly used Indian cooking oil. Canola oil at 200 degrees is actually the lowest smoke point of any common cooking oil, which makes it a worse choice for the way most Indian food is cooked.

Which Is the Best Cooking Oil in India? All 7 Major Oils Compared

To understand where mustard oil sits in the overall picture, here is how all the major cooking oils compare on the two most important parameters for Indian cooking, which are heat stability and smoke point:

Is Mustard Oil Safe to Eat in India? What Does the Research Actually Say?

For Indian adults using mustard oil in normal cooking quantities, the current scientific consensus is that there is no proven harm. India's FSSAI has approved sarson ka tel for cooking without any restrictions, based on traditional usage data and the absence of conclusive human studies linking normal mustard oil consumption to heart disease. This position is shared by public health researchers in South Asia.

The concern that exists is based on animal studies with high doses in rodents whose metabolic systems are simpler than humans. The same erucic acid that accumulates in rat heart muscle appears to be metabolized effectively by the human liver through a process called beta-oxidation. This is why communities in North India, West Bengal, Bihar and Odisha that have consumed mustard oil as their primary cooking fat for generations do not show patterns of the specific cardiac condition that erucic acid causes in animal research.

That said, scientists do not have a large long-term randomized human trial on erucic acid consumption because it is very difficult and expensive to run such a study. The precautionary approach that the EU and Australia have taken, which is to set limits rather than ban it, reflects this scientific uncertainty rather than confirmed danger.

The practical takeaway for an Indian family is this: mustard oil used for cooking in normal amounts is approved by Indian food safety authorities, has been part of the Indian diet for thousands of years, has the highest smoke point of any common Indian cooking oil and is significantly more affordable than alternatives like desi ghee. The scientific concern is real but unproven at human cooking doses.

Which Cooking Oil Should Diabetics Use in India?

For people managing diabetes in India, the choice of cooking oil matters because of how different oils behave under heat. When poly-unsaturated fatty acids break down during cooking, they release free radicals that cause oxidative stress in the body. Oxidative stress directly worsens insulin resistance, which is the root cause of Type 2 diabetes. This means the oil you cook with regularly has a real effect on how well blood sugar is managed over years, not just on one meal.

The practical recommendation based on the data in the table above is: use desi ghee for everyday cooking because it has the most heat-stable composition and the best overall fatty acid profile. For frying when you need larger quantities of oil, palm oil or groundnut oil are the best options. Mustard oil is acceptable and has the benefit of the highest smoke point, though the erucic acid question means it should be used thoughtfully.

Sunflower oil should be avoided for high-heat cooking. It is not that sunflower oil is poisonous, but heating 70 percent poly-unsaturated fat repeatedly over months and years means consistent exposure to free radicals through food. For someone already managing diabetes, reducing this oxidative load is a practical and cost-free improvement.

Why Does Palm Oil Get Bad Press When It Is the Healthiest Common Cooking Oil?

Palm oil comes from Malaysia, a small country with limited global advertising power. It does not have large multinational food companies promoting it with health messaging in international media. In fact it has consistently received negative coverage from Western media over the past few decades despite being the world's most consumed cooking oil by volume.

The contrast is revealing. Soybean oil is promoted heavily by American agricultural interests. Canola oil is promoted by Canadian agricultural exporters. Sunflower oil is promoted by European agricultural producers. All three of these countries have enormous media budgets and the ability to fund nutrition research that supports their preferred narratives. Malaysia does not have the same capacity.

The scientific reality is that palm oil has 90 percent saturated and mono-unsaturated fat combined, second only to desi ghee among common cooking fats, and a smoke point of 230 degrees Celsius. On both parameters that actually determine how much damage a cooking oil does when heated, it performs extremely well. The negative coverage around it is largely driven by economic competition, not by scientific evidence of harm.