Could eating steak increase your risk of diabetes? Yes, according to American experts probing the diet of over 200,000 adults collected over 36 years.

In the study, Harvard scientists found people with high levels of heme iron, the iron found in red meat, had an up to 26 per cent higher chance of type 2 diabetes. 

However, the same wasn't observed for plant-based sources of iron like beans and spinach, the experts said.

They added that their findings suggested cutting down on red meat and adopting a plant-based diet could help lower diabetes risk.

The experts also cautioned vegetarians and vegans who take heme iron supplements that they could be increasing their risk of developing type 2 diabetes.

Publishing their findings in the journal Nature Metabolism, the authors said their study added previous work supporting a link between heme iron and type 2 diabetes.

Their findings are based on data from a long-running study of over 200,000 nurses and healthcare professionals in the US.

Scientists examined how much iron participants consumed and in what form, be that heme iron, plant-based iron or from supplements such as iron boosting pills. 

This information was then compared to the participants health information to see if they had type 2 diabetes, accounting for various other health and lifestyle factors.

Those people with the highest heme iron intake were found to have a 26 per cent higher chance of having type 2 diabetes than those in the lowest intake group.

A separate analysis also examined the blood make-up of a sub-group of participants in the study.

This examined if they blood had any biomarkers, chemical signatures, linked to how the body processed iron as well as those for diabetes. 

Experts found higher heme intake was associated with more signs of type 2 diabetes in the blood, as well as lower biomarkers linked to lower diabetes risk, backing up their analysis. 

The authors said their study had implications for dietary guidelines and public health strategies to reduce diabetes in the population.

They also flagged the findings had implications for vegetarians and vegans adding heme iron to their diet who might think they are immune to negative health impact of red meat. 

Heme iron is also sometimes added to fake mats like vegan burgers in a bid enhance their 'meaty' flavour and appearance. 

Professor Frank Hu, an expert of nutrition and epidemiology and an author of the study, said: 'This study underscores the importance of healthy dietary choices in diabetes prevention.' 

He added: 'Reducing heme iron intake, particularly from red meat, and adopting a more plant-based diet can be effective strategies in lowering diabetes risk.'

Red meat has been demonised for decades due to a wealth of evidence suggesting that eating too much can raise the risk of heart disease, cancer and an early grave.

Although a good source of protein, vitamins and minerals, including iron, zinc and B vitamins, it can be high in salt and saturated fat.

When it comes to diabetes risk, red meat has previously been thought to contribute to the issue due to its saturated fat content and the salt content is some processed versions. 

Eating too much saturated fat can lead to an increased risk of obesity, itself a risk factor for diabetes, while some studies have linked too much salt, which is found in high amounts in red meats like bacon, has also been linked to type 2 diabetes risk.

The latest study is part of number pointing to heme iron as another risk factor with the substance believed to interfering with insulin production in the body. 

Insulin is the hormone our body makes to helps manage blood sugar levels. People with diabetes don't produce enough insulin naturally meaning their blood sugar becomes too high. 

However, the link between red meat and diabetes is observational, meaning it cannot be proven it, or its heme iron levels, are directly causing type 2 diabetes or if other factors are also at play.

The latest research was also on a cohort that was almost 80 per cent women, who were mostly white, meaning the findings may have limited implications for men and other ethnic groups. 

Another limitation is that data on participants' iron intake was self-reported meaning it could be influenced by errors. 

UK health chiefs recommend consuming no more than 70g of red meat — such as beef, lamb or pork — or processed meat — such as ham, bacon and salami — a day.

Red meat is rich in iron which is is essential for the production of red blood cells.

Not eating enough iron can increase the risk of anaemia. 

Tiredness, shortness of breath, heart palpitations, paler than usual skin and headaches are all tell-tale signs of an iron deficiency.  

Although a vegan or vegetarian diet can be high in iron, the iron in plant-based food isn't absorbed by the body as well as the iron found in meat, making it vital to eat the right food. 

Vegans are advised by the British Dietician Association to consume food or drinks containing vitamin C with plant based iron which helps the body more readily absorb this form of the mineral iron. 

Examples of vitamin C rich foods include orange, both fresh and juiced, strawberries, peppers, brussels sprouts and potatoes.

Men aged 19 and women over 50 need 8.7mg of iron a day and women who have periods between the ages of 19 and 49 need about 14.8mg a day, according to the NHS. 

For comparison, ground beef contains about 5.8mg per 160g serving and lentils contains 4.9mg per 125g serving. 

Pulses, wholemeal bread, fortified breakfast cereal, leafy green vegetables, nuts and dried fruit are all good sources of iron, according to the NHS. 

Approximately 5million people in the UK are living with diabetes, of which an estimated 850,000 are unaware they have the condition. 

A recent report from Diabetes UK suggests there has been a staggering 39 per cent rise in type 2 diabetes in people under 40 in a trend that's been blamed on rising obesity levels.