Cutting out meat causes people to lose around 4.2lbs (1.9kg) after three months, a study found.
Whereas following a Mediterranean diet, which is rich in olive oil, vegetables and fish, leads to people shedding 3.9lbs (1.8kg), the research adds.
The two diets are also thought to have comparable effects on the heart as both cause similar BMI and fat-mass changes, the research adds.
These similar outcomes may be due to both vegetarian and Mediterranean ways of eating limiting people's saturated fat intakes.
Study author Dr Francesco Sofi from the University of Florence and Careggi University Hospital, said: 'The take-home message of our study is that a low-calorie vegetarian diet can help patients reduce cardiovascular risk about the same as a low-calorie Mediterranean diet.
Near-identical weight loss between the diets
The findings did show that vegetarian diets lead to greater reductions in blood cholesterol levels.
Whereas Mediterranean ways of eating more effectively lower the amount of circulating fat in the blood.
Both of these have been linked to a reduced risk of heart disease.
Dr Cheryl Anderson, associate professor of preventive medicine at the University of California, San Diego, who was not involved in the study, said: 'The diets offer a possible solution to the ongoing challenges to prevent and manage obesity and cardiovascular diseases.
'Future research should compare the diets in patients at higher risk for heart disease and should also explore whether or not healthful versions of traditional diets around the world that emphasise fresh foods and limit sugars, saturated fats, and sodium can prevent and manage obesity and cardiovascular diseases.'
The findings were published in the journal Circulation.
How the research was carried out
The researchers analysed 107 overweight people with an average age of 51.
The study's participants had a low-to-moderate risk of heart disease.
They were assigned to follow either a low-calorie vegetarian or Mediterranean diet for three months.
All-natural pill turbocharges the Mediterranean diet
This comes after research released in December last year suggested scientists have found a way to turbocharge the health benefits of a Mediterranean diet.
Researchers from Cambridge University have created a supplement known as 'Ateronon Heart', which combines the heart-health benefits of a key component in tomatoes with milk; making the compound easier to absorb.
In a world first, they have been issued with a patent for the all-natural, over-the-counter product, which slows down the build-up of plaque in the arteries, preventing heart disease.
Previous studies show the supplement, which retails at £19.99 for 30 capsules, improves blood flow by 53 per cent.
Nick Sutcliffe, the Cambridge lawyer who steered the patenting process, said: 'There is increasing interest in natural ingredients.
'People are looking for cures and if they can find them in plants that is very much easier than developing synthetic drugs to treat disease.'
The Daily Mail
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