Eating too much butter could make you die earlier, a shocking new study has found?while eating vegetable oils increases your lifespan.

Researchers from the Harvard Medical School discovered that people who eat the most butter are 15 per cent more likely to die?of any cause?than those who eat the least.

But having a high intake of plant-based oils ? such as corn, olive and rapeseed ? appeared to make people healthier.

Tracking more than 221,000 Americans over a 50 year period, scientists analysing people?s diets by using food questionnaires made a groundbreaking discovery.

Swapping butter for plant-based oils ? of any type ? made people almost 20 per cent less likely to die.

In fact, every 10g per day increase in plant-based oils lowered the risk of death from cancer by 11 per cent and decreased heart disease death risk by six per cent.

A 10g daily increase of butter, meanwhile, raised the risk of cancer death by 12 per cent.

And by simply switching out a pad of butter for the equivalent amount of seed oil, participants lowered their risk of death by 17 per cent.

In total, 50,932 participants died during the study period ? with 12,241 due to cancer and 11,240 due to heart disease.

Now, experts are calling for Britons to take heed.

?This is an important study that shows that people who chose to eat butter don?t live as long as those who choose to eat vegetable oils,? said Dr Tom Sanders, professor emeritus of nutrition and dietetics at King?s College London.

?Butter is high in saturated fat, contains some trans fatty acids but is very low in polyunsaturated fats.

?Whereas unhydrogenated soybean, canola and olive oils are low in saturated fatty acids but high in unsaturated fats.

?The take-home message is that it is healthier to choose unsaturated vegetable oils rather than butter.

This is particularly relevant as there has been much negative publicity about vegetable oils on social media, which are based on unfounded claims of potential harmful effects, rather than deaths as described in the present study.

Saturated fats have long been known to contribute to increased cholesterol levels and a higher risk of heart disease.

This occurs when a build-up of fatty deposits narrow blood vessels and increase the risk of stroke.

Excess consumption can also lead to weight gain, a risk factor for type 2 diabetes.

Butter is primarily composed of saturated fat, leading the British Heart Foundation to advise people worried about cholesterol to swap it for margarine, which is made of vegetable oils.

These contain a higher proportion of unsaturated fats like polyunsaturated and monounsaturated fats, which are considered beneficial for heart health.

But not all oils are created equal.

Seed oils ? a category of vegetable oil including rapeseed, sunflower, flaxseed, corn and grapeseed ? have recently come under criticism from scientists linking them to conditions like type 2 diabetes, heart disease, depression and even Alzheimer?s

In fact, two new studies have even suggested these oils may be driving up cancer rates.

This is because seed oils contain high levels of omega-6 fatty acids, substances thought to promote inflammation ? which helps cancers grow and prevents the body from fighting tumours.

A study published recently in Clinical Oncology found that men with early prostate cancer who removed seed oils from their diet and consumed more foods rich in omega 3s, such as salmon, saw the disease progress more slowly.

But others disagree, saying omega 6 oils are beneficial, and even essential, for our health.

Linoleic acid ? the most common form of omega 6 in seed oils ? helps maintain healthy skin and forms a part of cell membranes.

And research also shows that people with a higher intake of linoleic acid have a lower risk of dying from heart disease, due to its ability to lower levels of ?bad? cholesterol. (Daily Trust)

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