What you eat has been proven to influence your risk of heart disease, yet confusion still reigns around which foods help to lower blood pressure and cholesterol. In the latest of two papers published in the Journal of the American College of Cardiology, cardiologist Andrew Freeman and a team of experts revealed exactly how to eat to improve your heart health. Some of the results may surprise you.
Three to five cups a day
Good news for coffee drinkers; Freeman and his team concluded that coffee consumption is linked to a lower risk of cardiovascular death, and that there is no association between coffee and raised blood pressure. There is so much more to coffee than caffeine, and it is the heart-healthy antioxidants it contains that hold the benefits. In July, researchers reported in the JAMA Internal Medicine journal that coffee drinkers were at an eight percent lower risk of dying early even if they consumed only one cup a day. The benefits rose to 12 percent if people drank two to five cups a day, while those consuming a regular six or seven cups were a staggering 16 percent less likely to die from any disease during the duration of the study. It was suggested that coffee’s ability to improve insulin sensitivity and blood-sugar control was, in part, responsible for some heart protection. Another trial involving 25,138 men and women at Samsung International Hospital in South Korea found that those who drank three to five cups of coffee a day had the least risk of coronary calcium clogging their arteries, reducing the risk of a heart attack.
The British Heart Foundation (BHF) says that, while caffeine doesn’t cause irregular heart patterns, some people are more sensitive to it and find it causes palpitations. If this applies to you, limit your caffeine intake, but otherwise four or five cups a day won’t damage your heart. “What you add to your coffee is more damaging,” says Victoria Taylor, a dietician at the BHF. “Avoid sugar and syrups, cream, and toppings.”
Daily serving of peas, beans, or lentils
“We should be incorporating more beans and bean dishes, like hummus, into our diets to promote heart health,” writes Freeman. Chickpeas, from which hummus is made, contain significant amounts of fibre, which helps to lower cholesterol in the blood. All legumes, says Freeman, “are affordable and a rich source of protein”. In 2014, researchers at the Clinical Nutrition and Risk Factor Modification Centre at St Michael’s Hospital in Toronto recommended eating one serving a day of beans, peas, chickpeas, or lentils after their research showed it reduced “bad cholesterol” by five percent, lowering the risk of cardiovascular disease (CVD) by five to six percent.
Linda Main, a dietetic adviser to Heart UK, a cholesterol advice charity, says that chickpeas and other pulses have a low glycemic index (GI), “meaning they hit the bloodstream more slowly than some foods”. They also tend to replace animal protein in a meal. “Beans, peas, and lentils are good alternatives to meat because they’re lower in fat and higher in fibre,” Taylor says.
Strawberries and Blueberries
More than three servings a week
All berries are a good addition to a heart-healthy diet, but strawberries and blueberries top the lot, according to Freeman’s paper, thanks to their ability to “induce protective antioxidants”. As part of the Nurses’ Health Study, a key US research program involving 93,600 women, researchers from the Harvard School of Public Health showed that those who ate the most of these particular summer fruits — and consumed them at least three times a week — were at 32 percent lower risk of a heart attack than those consuming the berries once a month or less. So potent were the effects that even if they had eaten a lot of other fruits and vegetables, the female subjects were more likely to suffer heart attacks if they avoided strawberries and blueberries.
It’s thought that the high levels of flavonoids — antioxidant compounds found in many plants — that are present in strawberries and blueberries help to combat blocked arteries. Although the Harvard study involved only women, its findings apply equally to men, says Taylor. “There’s some very interesting work being done by some researchers who specifically recommend berries for improving vascular circulation,” she says. “Remember that they should be eaten all year round and that frozen berries are just as good for you as fresh.”
Maximum of 30g a day
“Nuts are one of the few foods that have medical backing as a health aid,” says Helen Bond, a dietician and a spokeswoman for the British Dietetic Association. “Even the World Health Organization says that we should try to consume more to reduce cardiovascular disease.” Nuts, including cashews and pistachios, are rich in nutrients such as vitamin E, minerals, good fats, and dietary fibre. They are also known to have a prebiotic effect, meaning that they selectively feed our good gut bacteria.
Last year, a large study from the Harvard School of Public Health suggested that a handful of hazelnuts, cashews, pistachios, or Brazil nuts five times a week can cut the risk of heart disease by up to a quarter. At Penn State University, scientists showed how eating almonds daily boosted levels of “good” high-density lipoprotein cholesterol, while improving the way it removes cholesterol from the body. The downside is that nuts are high in calories, so Freeman and his colleagues advise no more than 30g a day and to choose raw nuts (preferably with the skin on for a fibre bonus).
Kefir, Tempeh, and Kombucha Tea
Four to five times a week
According to Freeman’s team, the benefits of these fashionable fermented foods is due to the effect they have on our microbiome, the vast ecosystem of bacteria, yeasts, and fungi that inhabit our gut. “There’s a huge amount of very positive research looking at the impact of a healthy microbiome and how that affects cholesterol levels and cardiovascular health,” says Main. “There appear to be benefits from eating more of low-salt fermented foods like kefir.”
This year, research from King’s College London and the University of Nottingham’s school of medicine, published in the European Heart Journal, concluded that the greater the diversity of “good bacteria” in our digestive systems, the lower the risk of hardened arteries and cardiovascular disease. Make sure you select foods fermented with bacteria, not vinegar, for their gut-friendly effects and avoid those with too much added salt.
One or two times a week
It’s nutritious, filling, and considered worthy of mention as a possible addition to your diet because of the “emerging data for CVD and risk-factor improvement”, say Freeman and his team. One way it appears to help is through weight control. Scientists have confirmed that different types of seaweed contain varying amounts of compounds that are an enemy to the expanding waistline. Among these are fucoxanthin found in wakame seaweed that has been shown, in small studies, to burn fatty tissue, and alginates, a type of dietary fibre found in seaweed that blocks the action of the digestive enzyme pancreatic lipase, whose job is to break down fat.
Three times a week
According to the new paper, mushrooms “have an anti-inflammatory effect and antioxidant benefits” and we should be eating more for the good of our heart. Trials by Robert Beelman, a professor of food science and the director of the Center for Plant and Mushroom Foods for Health at Penn State College of Agricultural Sciences, published recently in the Food Chemistry journal, showed that mushrooms contain unusually high levels of two antioxidants — ergothioneine and glutathione — and these have a powerful effect in controlling the production of free radicals in the body. At high levels, free radicals have been linked to illnesses associated with ageing, including coronary heart disease. Beelman’s results show that all mushrooms contain the nutrients, with porcini mushrooms having the highest levels, but, he says, even button mushrooms have “over ten times more than any other known food”.
One to two daily servings
Leafy green vegetables are a rich source of nitrates — compounds that are converted by the body to nitrite and then nitric oxide, a molecule that relaxes and widens blood vessels. A growing body of evidence supports the ability of nitrates to help the heart. In one study, funded by the BHF and conducted at the universities of Cambridge and Southampton, it was shown that the nitrates in spinach and kale, as well as in beetroot, help to thin blood and assist oxygen to get where it is needed in the body. “We know that the more fruit and vegetables we eat, the better news it is for our hearts,” says Taylor. “And leafy green vegetables, with their particular benefits, should be a very important part of the diet.”