Low-carb slimming diets may clog¹ arteries² and increase the risk of heart attacks and strokes, a study suggests.

一项调查建议，低碳节食餐可能阻塞动脉，增加心脏病和中风危险。

Low-carb dieters base meals on meat dishes

Diets based on eating lots of meat, fish and cheese, while restricting carbohydrates³（碳水化合物，糖类） have grown in popularity in recent years.

But the Beth Israel Deaconess Medical Center found such eating habits caused artery⁴ damage in tests on mice.

The researchers and independent experts both agreed a balanced diet was the best option.

Low-carb diets have attracted a lot of attention and controversy⁵ after a surge（汹涌，澎湃） in interest in them in the 1990s.

The Israeli team decided⁶ to investigate their impact on the cardiovascular system（心血管系统） after hearing of reports of people on the diets suffering heart attacks.

They fed the mice three different diets - a standard mouse type, a western diet which was high in fat, and a low-carb, high-protein version, the journal Proceedings⁷ of the National Academy of Sciences reported.

The low-carb diet did not affect cholesterol⁸（胆固醇） levels, but there was a significant difference on the impact on atherosclerosis - the build-up of fatty plaque⁹（名牌，徽章） deposits in the arteries that can lead to heart attacks or strokes.

After 12 weeks, the mice eating the low-carb diet had gained less weight, but developed 15% more atherosclerosis than those on the standard mice food. For the western diet group there was 9% more atherosclerosis.

The team could not be certain why the effect was seen, but thought low-carb diets may affect the way bone marrow¹⁰ cells effectively clean arteries of fatty deposits.

Adverse¹¹ effects

Lead researcher Anthony Rosenzweig said the findings were so concerning to him that he decided to come off the low-carb diet he was following.

He added: "Our research suggests that, at least in animals, these diets could be having adverse cardiovascular effects.

"It appears that a moderate and balanced diet, coupled with regular exercise, is probably best for most people."

Joanne Murphy, from the Stroke Association, agreed following a balanced diet was the best advice.

"We know that foods such as red meat and diary products, which are high in protein, also contain high levels of saturated¹² fat（饱和脂肪）. These fats then cause the build up in the arteries."

But she added the research was still at an early stage and she wanted to see more work done on the subject.

Ellen Mason, from the British Heart Foundation, said it was difficult to apply the findings to humans.

But she added: "Low-carb, high-protein diets are not considered as healthy as eating a balanced diet, which is good for health because we get the different nutrients¹³ our body needs by eating from the different food groups every day."