Berries in general are good for health and raspberries and cranberries are currently the popular berries in the consumer market for heart health. Not only are they sweet, they are also filled with vitamins and minerals. In terms of heart health, raspberry contributes its potent antioxidants; alpha- and beta-carotene, lutein, zeaxanthin and cholin. Raspberries are also rich in polyphenols such as anthocyanin (ACN), flavonols and ellagitannins, all of which reduce oxidative damage from free radicals help promote a healthy heart.
Special attention needs to be given to ACNs, a flavonoid that has been shown to suppress the inflammation that may lead to cardiovascular disease. Aedin Cassidy led an 18-year study tracking 93,600 women aged 25 to 42. She stated that their study showed that the regular sustained intake of anthocyanins from berries can reduce the risk of a heart attack by 32 percent in young and middle-aged women.
Many may argue that the study cannot prove that ACNs cause the observed effects, as these foods contain many other potentially bioactive components apart from ACNs. In 2015, researchers used genetically modified ‘purple tomatoes’ packed with high levels of ACNs, and equivalent ACN-free red tomatoes to feed mice. The results showed that the consumption of tomato anthocyanins significantly reduces atherosclerosis.
Cranberry is a rich source of phytonutrients, including proanthocyanidins, anthocyanins and phenolic acid. It is popular as a prevention for urinary tract infection, but is also gaining recognition for its cardiovascular benefits.
In a recently published study, researchers uncovered a potent, dose-dependent relationship between cranberry juice and improved vascular function.
In a randomised, controlled crossover trial, researchers gave 10 healthy male subjects, between the ages of 18- 40 years, 450 ml of sweetened cranberry juice made from concentrate. The cranberry concentrate was prepared with water to concentrations ranging from 0 to 117 percent. Non-invasive measurements of vascular function including flow-mediated vasodilation (FMD), blood pressure and arterial stiffness were performed at baseline and at one, two, four, six and eight hours post-consumption.
Blood and urine samples were collected for 24 hours following consumption to detect changes in plasma and urinary cranberry-derived polyphenols. Across the board, all of the cranberry juices benefited FMD. The highest concentration of cranberry-polyphenol juice also showed improvements in systolic blood pressure.
“Our results lay the groundwork to better understand the array of potential vascular and cardiovascular health benefits of cranberry polyphenols,” noted Dr Rodriguez-Mateos, principal author of the paper. “Significant improvements in vascular function from drinking two cups of cranberry juice suggest an important role for cranberries in a heart-healthy diet.”
The downside of raspberries and cranberries are that although they are relatively common in Europe and US, they are not common in Asia, making them slightly expensive. However, other berries are available such as strawberries, blueberries and blackberries, which also have similar health benefits.
The avocado originated in Mexico, Central or South America and was fi rst cultivated in Mexico as early as 500 BC.
The fruit is rich in oleic acid, which helps to lower the blood concentration of low-density lipoproteins cholesterol by up to 22 percent, raise the amount of high-density lipoproteins cholesterol by 11 percent, and reduce blood triglycerides by up to 20 percent. It has also been suggested that oleic acid has beneficial effects on genes linked to cancer.
Avocado oil consists of 71 percent monounsaturated fatty acids, 13 percent polyunsaturated fatty acids, and 16 percent saturated fatty acids, which helps to promote healthy blood lipid profiles.
This gives the avocado the ability to reduce the ‘bad’ cholesterol in your body while increasing the ‘good’ ones, and also potentially reduces the risk of cancer.
Currently, there are eight preliminary clinical studies showing that avocado consumption helps to support cardiovascular health, and exploratory studies suggest that avocados may support weight management and healthy ageing as well.
There was a time when consumers were discouraged from eating nuts as they are fatty and high in calories; this is no longer the case.
Tree nuts such as walnuts, pecans and almonds are especially prized for their good taste, high content of monounsaturated fatty acids and vegetable-omega-3s, and protein. To reduce the risk of heart disease by 50 percent, it is recommended that 30 g of nuts should be consumed at least five times a week. The disadvantage of tree nuts is that they can be quite expensive, and may not be easily accessible to some consumers.
Just a few years ago, the health benefits of peanuts were greeted with much scepticism in the nutritional industry as peanuts are not nuts. They are in fact legumes.
A study published in JAMA Internal Medicine showed that the peanut is just as potent as true nuts in terms of health benefits. The team found that in more than 200,000 people, from Savannah to Shanghai, those who regularly ate peanuts and other nuts were substantially less likely to have died of any cause—particularly heart disease—over the study period than those who rarely ate nuts.
In a Dutch study published in June 2015, researchers found that eating half a handful of peanuts each day could prevent early death, not just from cardiovascular disease, but also from respiratory diseases, dementia, diabetes and cancer.
Professor van den Brandt, an author of the study, said that peanuts contain various compounds such as, monounsaturated and polyunsaturated fatty acids, various vitamins, fibre, antioxidants, and other compounds, that may contribute to the lower death rates. However, peanut butter has no effect on mortality rates. This is likely due to the salt and trans-fatty acids contained in peanut butter inhibiting the protective effects of the peanuts themselves.
Over the past two decades, soy foods have been the subject of a vast amount of research, primarily because they are uniquely rich sources of isoflavones. Although isoflavones are classified as both phytoestrogens (plant hormone) and selective oestrogen receptor modulators, they are said to have the potential to improve risk factors for cardiovascular disease.
Soy bean is low in saturated fat and a source of essential fatty acids—the omega-6 fatty acid linoleic acid and the omega-3 fatty acid alpha-linolenic acid. In addition, soy protein has been shown to directly lower blood low-density lipoprotein (LDL) cholesterol concentrations, while isoflavones improve endothelial function and possibly slow the progression of subclinical atherosclerosis.
However, in 2006 the American Heart Association Science Advisory assessed 22 randomised trials and found that isolated soy protein with isoflavones, as compared with milk or other proteins, had the lowest decreased LDL cholesterol concentrations—the average effect was 0.3 percent. This reduction is very small relative to the large amount of soy protein tested in these studies, averaging 50 g, which is about half the usual total daily protein intake.
No significant effects on HDL cholesterol, triglycerides, lipoprotein(a), or blood pressure were evident. Among 19 studies of soy isoflavones, the average effect on LDL cholesterol and other lipid risk factors was minimal.
More recently in 2015, a team in Singapore published their studies in the Journal of Nutrition on the analysis of the presumed cardiovascular benefits of long-term intake of soy food by middle-aged Chinese adults. They concluded that soy protein intake was not significantly associated with cardiovascular disease mortality. In fact, their results indicated the possibility of a slightly increased risk associated with high soy protein intake in men, though this needs further investigation.
While the effects of soy is minimal on cardiovascular health, there are currently promising studies for the beneficial intake of soy in menopausal women.
Salmon is a saltwater fish and is one of the top foods when it comes to cardiovascular health. It is a good source of protein and is rich in unsaturated fats known as omega-3.
Omega-3s have an anti-clotting effect and the ability to lower triglycerides. Studies have also shown that it reduces the risk of irregular heartbeat which may lead to sudden death, inflammation, stroke and heart failure.
To make the salmon even more attractive to the city dwellers, apart from heart health, a 2012 American study found that fish oil also offers protection against adverse cardiac effects associated with air pollution exposure. Fish oil is now the third most widely used dietary supplement in the US, according to the National Institutes of Health in the US.
The American Heart Association advises at least two servings per week; each serving should be 3.5 ounces (99.2 g). This will provide close to the recommended 250 mg of DHA and EPA which in return helps reduce risk of death from a heart attack by up to one-third.
Other alternatives to salmon are tuna, sardines or mackerel. Not all fishes are heart friendly though. For example, tilapia and catfish do not seem to be as heart-friendly, as they contain higher levels of unhealthy fatty acids.
There are many versions of olive oil, including virgin oil, refined olive oil, pomace, extra-virgin olive oil. The difference between each version of olive oil is in the ways that the oil is processed.
In short, virgin olive oil and extra-virgin olive oil are produced by mechanically pressing ripe olives. They both contain multiple bioactive and antioxidant components such as polyphenols, phytosterol and vitamin E. The difference between the two is that the virgin olive oil has an acidity of less than 1.5 percent. The extra-virgin olive oil, known as the best quality of the range, has the most intense taste and its acidity is less than one percent.
Common olive oil is obtained from a mixture of virgin and refined oil (usually more than 80 percent is refined) and so has fewer antioxidant and anti-inflammatory compounds. The refined oil loses phytochemicals during the refining process, therefore it is mixed with virgin olive oil to enhance the flavour, constituting the common olive oil.
All olive oil provides the full amount of monounsaturated fats, which, like salmon, decrease the amount of ‘bad’ fats and increase the amount of ‘good’ fats in the body.
A study from Spain followed 7,216 Mediterranean men and women at high cardiovascular risk for a median period of 4.8 years. Participants who consumed the highest total olive oil and extra-virgin olive oil had a cardiovascular disease risk reduction of 35 and 39 percent respectively. The association between cardiovascular events and extra-virgin olive oil intake were significant in the Mediterranean diet (diets that were supplemented with nuts and extra-virgin olive oil) intervention groups but not in the control group (controlled low-fat diet).
Studies have shown that olive oil also contributes to a variety of other health benefits, including protection against rheumatoid arthritis, providing a source antioxidants, and enhancing insulin levels and blood sugar control.
The extra-virgin olive oil contributes the most significant nutritional value to human health and is also the most costly amongst the spectrum.
Green tea was first introduced to the Western world in the 17th century when a ship of the Dutch East India Company brought it from China to Amsterdam.
There is currently an abundance of scientific literature that claims green tea is ‘one of the healthiest beverages on the planet’ as green tea is rich in antioxidants and nutrients that have positive effects on not just cardiovascular health, but on overall health such as anti-ageing, anti-diabetic and anti-inflammatory.
Evidence is accumulating that catechins and theaflavins, which are the main polyphenolic compounds of green and black tea, respectively, are responsible for most of the physiological effects of tea. Various studies suggest that the polyphenolic compounds present in green and black tea are associated with beneficial effects in the prevention of cardiovascular diseases, particularly of atherosclerosis and coronary heart disease.
A study in China found that of patients who underwent coronary arteriography for the first time found that when comparing patients who consumed green tea to those who did not, the patients who drank tea showed a reduced risk of coronary artery disease. The results though, applied to only male patients. There was no inverse association found between green tea consumption and coronary artery disease in female patients.
Additionally, in a 2006 Japanese meta-analysis study, data from nine studies involving 4,378 strokes among 194,965 individuals was pooled. Individuals consuming more than or equal to three cups of tea per day had a 21 percent lower risk of stroke than those consuming less than one cup per day.
The most notable finding from this study was the reduction of cardiovascular death in those who consumed the most amount of green tea. Women and men who consumed five or more cups of green tea has a reduced risk of dying from cardiovascular disease by 31 percent and 22 percent, respectively. The research also showed that women who drank five cups or more of green tea had a 42 percent lower risk of stroke, compared to those who drank less than a cup per day.
Although the studies show very positive results, many of them have limitations, and thus do not conclude decisively that green tea is indeed good for the heart. One reason for this is very simple. In May 2006, the US Food and Drug Administration (FDA) rejected a petition from tea makers to allow tea labels to claim that green tea reduces the risk of heart disease, saying that there is no credible evidence to support that claim.