When it comes to choosing an oil or fat for cooking your food, you'd be forgiven for thinking sunflower oil may be a healthier alternative to lard.
But recent research has shown that lard and other animal fats may not be deserving of their unhealthy reputation.
The research was carried out as part of the BBC show Trust Me I'm A Doctor.
As part of the show, a group of researchers aimed to answer the question "which fats and oils are best to cook with?".
They gave a group of volunteers in Leister a variety of fats and oils - including sunflower oil, vegetable oil, corn oil, cold pressed rapeseed oil, olive oil (refined and extra virgin), butter and goose fat - and asked them to use the products in their everyday cooking.
The volunteers were also asked to collect left over oil after cooking, which was then analysed by a research team at Leicester School of Pharmacy at De Montfort University.
Writing on the BBC, one of the researchers, Michael Mosley, explains that when oils and fats are heated in frying or cooking, their molecular structure changes.
"They undergo what's called oxidation - they react with oxygen in the air to form aldehydes and lipid peroxides. At room temperature something similar happens, though more slowly. When lipids go rancid they become oxidised," he says.
Previous research has suggested that consuming or inhaling aldehydes may increase the risk of heart disease and cancer.
In the BBC show, the research team found that the oils which were rich in polyunsaturates - most notably corn oil and sunflower oil - generated "very high levels of aldehydes".
"Sunflower and corn oil are fine as long as you don't subject them to heat, such as frying or cooking," lead researcher Professor Martin Grootveld commented.
"If I had a choice between lard and polyunsaturates, I'd use lard every time."
It has long been believed that saturated fats are detrimental to our health, with the NHS warning against consuming too many saturated fats, including lard.
But the latest research on oils comes at a time when public and medical opinion on saturated fats seems to be shifting.
Instead of blaming saturated fats for the rise in obesity and cases of heart disease, more recent thinking has looked at sugar as the cause.
The British Heart Foundation (BHF) recently funded a study which suggests there’s not enough evidence to back the current UK guidelines on the types of fat we eat.
"We think more research is needed before suggesting any major changes to healthy eating guidance," their website states.
But for now, BHF gudeilines on oils are lard read: "Swap butter, lard, ghee and coconut and palm oils with small amounts of monounsaturated and polyunsaturated fats, such as olive, rapeseed or sunflower oils and spreads."
The BBC research does not necessarily mean we should we go out and buy lard immediately, either.
Grootveld believes the ideal compromise for cooking could be olive oil, as it made up of only 10% polyunsaturates.
Trust Me I'm A Doctor is on Wednesdays at 8pm on BBC2.