A vegan lifestyle may be the key to a healthy heart, research suggests.
The pros and cons of cutting out animal products have long been debated. Some argue good-quality meat and dairy are a rich source of protein, iron and vitamin B12, while others warn steak, butter and cheese can contain high amounts of saturated fat.
To better understand the potential benefits of a vegan lifestyle, scientists from the University of Naples Federico II analysed the available evidence.
Results suggest that upping our intake of plant-based products – like whole grains, lentils, nuts, fruits and vegetables – reduces the risk of atherosclerosis.
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Atherosclerosis occurs when the arteries become clogged with plaque, causing them to harden and narrow. This then restricts blood flow to vital organs, raising the risk of a heart attack.
Heart disease causes around one in four deaths in the UK alone, killing someone every three minutes.
"Food choices" are said to be the most important factor "undermining health and wellbeing", accounting "for as much as almost 50% of all CVD [cardiovascular disease] deaths", the Naples scientists wrote in the journal Cardiovascular Research.
On a global scale, more than 9.1 million premature deaths that occur due to heart disease "are attributable to diet-related risks".
As well as increasing our intake of plant-based foods, the Naples results reinforce the advice to limit our salt consumption.
The NHS recommends adults eat no more than around one teaspoon of salt a day. A high intake can raise our blood pressure, putting us at risk of heart disease and strokes.
"The evidence is highly concordant in showing that, for the healthy adult population, low consumption of salt and foods of animal origin, and increased intake of plant-based foods – whole grains, fruits, vegetables, legumes, and nuts – are linked with reduced atherosclerosis risk," wrote the scientists.
"The same applies for the replacement of butter and other animal/tropical fats [like coconut or palm oil] with olive oil and other unsaturated-fat-rich oil."
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Despite the results, "some novelties emerge".
Red or processed meat – like salami, pâté and low-quality sausages – pose a greater heart disease risk than poultry, for example.
The scientists also question the advice to opt for low-fat dairy, arguing "both full-fat and low-fat dairies, in moderate amounts and in the context of a balanced diet are not associated with increased CVD risk".
Small amounts of cheese and "regular yoghurt consumption" may even have a "protective effect".
Fish has long been known to be a heart-healthy source of protein, which "is also supported by the latest evidence, although there might be sustainability concerns", wrote the scientists.
Perhaps surprisingly, the results support not only limiting alcohol, but also drinking tea and coffee in moderation. This somewhat contradicts recent research, which found coffee reduces the risk of an irregular heart beat and even heart failure.
Soft drinks, like soda, are also directly linked to an increased heart disease risk, the Naples results suggest.
Cutting back on your favourite foods may sound like a daunting prospect.
In light of the Naples study, dietitian Michelle Routhenstein told The Washington Post: "I highly recommend not to go from zero to 100."
Routhenstein, who lives in New York, advises people make just two or three changes at a time.
"I also find focusing on all the good things we can eat is easier in this transition," she added.
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