New York, Mar 6 (IANS): Looking to try weight loss by following a 'keto' diet? You could be at twice the risk of suffering heart attack and stroke, warns a study.

Researchers from the University of British Columbia in Canada showed that the popular weight-loss dietary programme, which includes very low amounts of carbohydrates and high amounts of fats, is associated with higher blood levels of 'bad' cholesterol.

It is also linked with a two-fold heightened risk of cardiovascular events such as chest pain (angina), blocked arteries requiring stenting, heart attacks and strokes, they said while presenting the study at the American College of Cardiology's Annual Scientific Session.

"Our study found that regular consumption of a self-reported diet low in carbohydrates and high in fat was associated with increased levels of LDL cholesterol -- or 'bad' cholesterol --and a higher risk of heart disease," said lead author Iulia Iatan, from St. Paul's Hospital and University of British Columbia's Centre for Heart Lung Innovation in Vancouver, Canada.

For the study, Iatan and her team analysed 305 participants who were compared with 1,220 individuals eating a standard diet.

They defined a low in carbohydrates and high in fat diet as consisting of no more than 25 per cent of total daily energy or calories from carbohydrates and more than 45 per cent of total daily calories from fat.

Compared with participants on a standard diet, those on a keto-like diet had significantly higher levels of both LDL cholesterol and apolipoprotein B (apoB) -- a protein that helps carry fat and cholesterol through the human body.

Previous studies have shown that elevated apoB may be a better predictor than elevated LDL cholesterol for risk of cardiovascular disease, Iatan said.

After about 12 years of follow-up, the team found that people on the keto-like diet had more than two-times higher risk of having several major cardiovascular events, such as blockages in the arteries that needed to be opened with stenting procedures, heart attack, stroke and peripheral arterial disease.

In all, 9.8 per cent of participants on the keto-like diet experienced a new cardiac event, compared with 4.3 per cent of those on a standard diet, a doubling of risk for those on the keto-like diet.

Iatan cautioned people who are considering going on an LCHF diet.

"Before starting this dietary pattern, they should consult a healthcare provider. While on the diet, it is recommended they have their cholesterol levels monitored and should try to address other risk factors for heart disease or stroke, such as diabetes, high blood pressure, physical inactivity and smoking."

However, the researchers noted that their study "can only show an association between the diet and an increased risk for major cardiac events, not a causal relationship," because it was an observational study, but their findings are worth further study.