Eating oily fish like salmon and sardines twice a week may increase the risk of dying from cardiovascular disease by more than a fifth, a new study reveals.
Canadian researchers at McMaster University have previously collected four studies to look at data from more than 190,000 people from 58 countries.
Sudden mortality and overall mortality rates fell 21 percent and 18 percent, respectively, among people with cardiovascular disease who ate at least 175g (six ounces) of oily fish per week – about two distributions.
They were also 16 percent less likely to suffer a heart attack or stroke over the next decade.
Although the benefit has not been seen in people with normal health, the omega-3 fatty acids in fish are known to be good for the human heart in general.
Two servings of fish a week could help prevent people with heart disease from having a heart attack or major stroke, according to the study
Researchers say eating fish can help fight cardiovascular disease, or CVD – a common term for conditions that affect the heart or blood vessels, including pressure. -blood, stroke and viral depression.
The combined form of all forms of CVD makes it the leading cause of death worldwide, an estimated 17.9 million lives each year, according to the World Health Organization (WHO).
Heart and circulatory diseases cause more than a quarter of deaths in the UK – more than 160,000 each year.
‘Dietary guidelines generally encourage the consumption of a variety of fish, preferably oily varieties – for example salmon, sardines, tuna and mackerel – at least twice a week for CVD prevention,’ said the study’s author. Dr. Andrew Mente at McMaster University, Ontario.
‘In our study, the risk of CVD was lowest with a moderate amount of fish – that is, at least 175 g a week (6oz) or around two distributions.’
Oily fish is believed to be good for human health in a number of ways, with potential benefits for the heart, eyes and brain, and for those with arthritis or depression.
Seafood such as salmon, trout, sardines and mackerel are high in omega-3 fats that reduce inflammation throughout the body.
Cardiovascular disease is the term for all types of disease that affect the heart or blood vessels, including coronary heart disease (clogged artery), which can cause heart attack, stroke, congenital heart defects and peripheral artery disease
One type of omega-3 acid, DHA, is essential for brain growth and development in infants and necessary for maintaining normal brain function in adults.
The human brain contains nearly 60 percent fat and about 40 percent of this is DHA.
The American Heart Association says people need to replace meat, which is high in saturated fat, for oily fish that provide essential omega-3 fats.
They have anti-inflammatory effects that can counteract the narrowing of arteries that can cause a heart attack or stroke.
For this new study, data were combined from studies involving 191,558 participants worldwide – approximately 51,000 of whom had CVD.
Consumption of fish was recorded using valid food frequency questionnaires. Participants were then tracked for more than nine years.
The team found that there was a lower risk of primary CVD and overall mortality associated with higher fish intake of at least 175g per week among high-risk people or patients with vascular disease, but not in numbers. general
Interestingly, the analysis found no additional protection from more than two distributions.
‘On this basis, two distributions of fish per week may be the minimum amount of fish required for maximum benefit – a sum which is consistent with current prevention proposals. CVD, ‘said Dr Mente.
”[There was] little additional benefit with higher inclusion among patients with vascular disease. ‘
Sardines (pictured) are oily fish, such as herring, pilchards, salmon, sprats, trout and mackerel.
British Heart Foundation dietitian Victoria Taylor, who was not involved in the study, said we should all eat at least two portions of fish a week including at least one oily fish.
‘Oily fish gives us a type of omega-3 that we don’t get from other foods and this can help keep your heart healthy,’ Taylor said.
‘Oily fish usually have oily or dark flesh – omit skin color. Think salmon, trout, pilchards or sardines.
This could be sardines on toast, mackerel salad or baked salmon with peas and potatoes. Fresh, frozen or tinned counts. ‘
A recent study by Public Health England found that tuna does not contain high levels of polyunataturated fat in other oily fish. It is now considered a white fish like cod.
‘Whether it’s oily or white, fish is a good source of protein and has a range of vitamins and minerals,’ said Taylor.
Eating more fish can help you cut down on red and processed meat. ‘
Oily fish is also part of the Mediterranean-style diet, which is also made up of vegetables, fruits, legumes, nuts, beans, grains, grains and unsaturated fats such as olive oil.
Research on this way of eating has shown that there is a lower risk of developing problems such as type 2 diabetes, high blood pressure and elevated cholesterol, all of which are risk factors for heart disease.
Researchers have also found that people who follow a traditional Mediterranean-style diet are more likely to have a longer life and are also less likely to be obese.
The study was published in JAMA Internal Medicine.