Legumes, Nuts, Fruits, Whole Grains and Functional Botanicals Pump Up Heart-Health Appeal
Teasing out the nutrition factors that influence heart health is challenging, because the task is complicated by the modern trend toward obesity and sedentary lifestyle
According to the Centers for Disease Control, about one in four deaths in the US is attributable to heart disease. That’s more than 600,000 people every year. But even if the results aren’t initially fatal, heart disease is life changing. Nearly three- quarters of a million people per year have a heart attack due to coronary heart disease (CHD), the most dominant form of heart ailment.
CHD results from a narrowing of the arteries that feed the heart due to a buildup of atherosclerotic plaque. Plaque buildup is sinister, beginning without symptoms. Its progression continues until an individual experiences a noticeable decrease in performance capacity due to fatigue, as well as pain resulting from a reduction of blood flow to the heart.
A narrowed artery is susceptible to blockage by a clot that can cut off circulation to a portion of the heart muscle. This is a heart attack. If circulation is not restored to the affected portion of the heart within approximately 20 minutes, the tissue dies and is replaced by scar tissue.
Preventing the buildup of atherosclerotic plaque, and thus maintaining dynamic circulation to the heart, is at the core of all strategies to reduce the risk of heart disease. Lifestyle and risk of cardiovascular disease are closely linked.
A large number of population studies have amply demonstrated a dramatic decrease in cardiovascular event incidence for people following a routine of regular physical activity, healthy dietary pattern, normal BMI, moderate (or no) alcohol intake, and no smoking.
In general, the greater the adherence to such a healthy lifestyle, the greater the reduction in cardiovascular event incidence. The specifics, however, are more complex.
Teasing out the nutrition factors that influence heart health is challenging, because the task is complicated by the modern trend toward obesity and sedentary lifestyle. In addition, the incredibly wide variety of differences in individuals involving genetics, metabolism, and stress can counterbalance a healthful diet.
Many of the nutritional factors that reduce the risk for heart disease are essential parts of well-known dietary staples. At least, staples for some. Many such foods and ingredients are not necessarily staples in the modern Western diet.
When developing food and beverage products to help people reduce the risk of vascular and heart disease, several basics still apply. Observations over the past few decades have firmly established that vegetarians generally have lower blood pressures than the overall omnivorous population.
Studies also have demonstrated time and again that a diet high in fruits, vegetables, whole grains, legumes, and nuts—as well as dairy, fish, and poultry—correlates to reduced disease risk. Most of this approach is incorporated into the famous Dietary Approaches to Stop Hypertension (DASH) diet.
In 2012, a cross-sectional study (one that looks at an entire population as opposed to a select group) of more than 6,800 adults without cardiovascular disease (CVD) and of all ethnicities showed that the greater the adherence to the principles of the DASH diet, the more favorable the parameters associated with healthy heart function. These parameters included end-diastolic volume, stroke volume, and ejection fraction. In other words, the heart worked more efficiently with each beat.
Subsequent prospective studies (studies that follow a select group for an outcome) also showed that greater adherence to DASH principles was associated with significantly reduced risk of heart failure for both men and women (22% reduction and fr37% reduction, respectively). In 2013, a meta-analysis of more than 144,000 adults showed that adherence to a “DASH-like” diet resulted in about a 20% reduction in both CHD and stroke.
Approaching heart-health nutrition from a “good” vs. “bad” ingredients can lead to confusion. The best example is the demonization of ingredients such as carbohydrates, sugar, fat, and salt. Carbohydrates stand out because the category is so broad, containing everything from fruits and vegetables to sweets and pastries.
Protein is another example. While the past few decades have seen a greater public understanding of such healthful macro-ingredients as monounsaturated fats and functional flours, many consumers are still in the dark about protein’s role in health beyond simple tissue building and structure. This is partly because it still is a highly active area of study.
For example, one landmark study published in the Journal of Cardiovascular Nursing tested different levels of protein in low-calorie diets on obese subjects with mild to moderate heart failure and diabetes. The three diets tested during a 12-week period were high-protein/low-calorie, standard protein/low-calorie, and the standard American Heart Assn. diet.
The higher protein diet produced greater decreases in body weight, body fat, total and LDL cholesterol, and triglycerides. In addition, subjects on that diet showed greater improvements in HDL, exercise capacity, quality of life, and increased muscle mass.
It should be noted that the subjects in the high-protein group were encouraged to increase their intake of plant proteins at the expense of animal proteins. This was a short-term study on restricted calories, but the increase in plant-derived foods overall added more phytochemicals to the mix. This makes conclusions valuing the activity of the protein itself hard to confirm.
Last June, results of the “Intake of Different Dietary Proteins and Risk of Heart Failure in Men: The Kuopio Ischaemic Heart Disease Risk Factor Study” were published in the journal Circulation. The study examined the associations of proteins from different food sources with risk of heart failure in 2,441 men aged 42 to 60 years from baselines taken between 1984 and 1989. The subjects were followed for 22.2 years.
In that time, 334 incident heart failure cases were reported. Higher intake of total protein resulted in a trend toward increased risk of heart failure in this population. The specific effect of individual proteins was not conclusive and needs further study, but the overall trend contradicted the popular narrative that simply increasing protein at the expense of healthy carbohydrates is desirable, especially with respect to heart health.
In fact, most healthy carbohydrate sources are also good sources of plant proteins. All protein foods in moderation have their own benefits. Dairy proteins are rich in branched-chain amino acids. Fish are rich in long-chain omega-3 fatty acids, specifically EPA and DHA, which have anti-inflammatory properties and act as blood thinners.
The takeaway from all the studies, however, is that protein is absolutely essential to heart health and health in general. The caution is that protein should not be a primary source of calories. That’s because unlike carbohydrates and fats, protein contains nitrogen, which, while essential to protein synthesis, is also toxic in high amounts.
According to the National Institutes of Health, overloading the diet with protein can pose a metabolic burden on the bones and organs. A May, 2018, American Heart Assn. report revealed that middle-aged men on a high-protein diet from all protein sources showed a 33% higher risk of developing heart failure.
Vitamins and minerals play important roles in heart health as well. Thiamin (vitamin B1) deficiency, for example, causes the disease beri beri, which leads to congestive heart failure. In addition to vitamins and minerals, thousands of chemicals in plants (phytochemicals) have been shown to act as antioxidants, anti-inflammatories, and anti-cancer agents.
Vitamins, especially the lipid-soluble vitamins A, D, and E, all have a role to play in supporting healthy cardiovascular structure and function. Vitamin E is known as a powerful antioxidant, with its tocotrienol form exhibiting that capacity at several hundred times that of its tocopherol form.
Selenium is a mineral that functions as an endogenous antioxidant. It is necessary for proper function of thyroid gland and critical to the structure of the antioxidant glutathione peroxidase, which protects membranes.
Too much selenium is toxic, however. Selenium is a soil-dependent trace mineral. Often the amount in the body is dependent on the soil content, which determines the amount of selenium in food. In the US, selenium deficiency is rare, but in Europe, the soil is not so rich in selenium, so a deficiency can occur.
Copper and zinc are both minerals that helpcounteract dangerous oxygen radicals that result from normal cellular respiration. And iron, of course, is critical to overall oxygenation of the cells. Overall, vitamins and minerals have demonstrated—and continue to demonstrate—positive benefits to heart health and overall health in a number of clinical studies.
Members of a group of phytochemical compounds called flavonoids have been particularly closely associated with heart health. One of these, quercetin, is found in a number of vegetables and fruits, including apples, dark berries, cherries, peppers, spinach, kale and others. A study published in the June 2018 issue of the European Journal of Medicinal Chemistry, “Therapeutic potential of quercetin as a cardiovascular agent,” supported the cardioprotective effects of this unique plant compound.
Epidemiological evidence also suggests that foods rich in quercetin have positive health benefits, especially for the heart. Quercetin is believed to inhibit the oxidation of low-density lipoproteins (LDL cholesterol, high blood concentrations of which are a key factor in the creation of atherosclerotic plaque and have been linked to increased risk of heart and vascular disease).
Quercetin also has shown a capacity to reduce the risk of endothelium-independent vasodilation, lower adhesion molecules and other inflammatory markers, and reduce platelet aggregation. All of these can lead to blood clots.
Another class of phytochemicals well studied for potential heart benefits is polyphenols. This is a large group of more than 500 chemicals found in a vast number of foods. Many polyphenols have exhibited powerful antioxidant properties.
Last year, an article in Oxidative Medicine and Cellular Longevity reviewed some of the potential actions of polyphenols and polyphenol-rich diets. Lab studies reveal that polyphenols exhibit antioxidative and anti-inflammation effects. They reduce the reactive oxygen species (dangerous oxygen compounds that injure tissues and damage DNA) and inhibit the oxidation of LDL cholesterol.
Flavonoids and polyphenols and their potential cardioprotective effects could be why we see reduction of cardiovascular risk factors with increased use of fruits and vegetables, herbs and spices.
Polyphenol-rich foods include berries, leafy greens, nuts, chocolate, teas, potatoes, onions, shallots, and beans, as well as spices such as anise and cloves. Since oxidative stress is linked to a variety of cardiovascular disease risk factors, such as atherosclerosis, hypertension, diabetes, high cholesterol levels, and obesity, studies continue to help elucidate the potential role of various polyphenols as cardioprotective agents.
In many cases, the best way to add these compounds is through incorporation of whole foods, such as fruits and vegetables and other macroingredients, into a formulation. Inclusion of fruits or nuts can add flavor and texture to a product and provide the healthy components consumers seek.
The use of herbs and spices in the prevention and treatment of heart disease goes back thousands of years. Many heart disease medications have their roots in herbal medicine. The drug digitoxin, for example, long used to treat congestive heart failure, was derived from Digitalis purpurea (foxglove), a member of the plantain family.
Statin drugs that lower plasma cholesterol by inhibiting liver cholesterol synthesis have their origins in certain types of mushroom. In fact, mushrooms have been used as medicinal foods for several millennia. Many varieties are rich in anti-inflammatory components, including polyphenols, plus other phytochemicals such as indoles, mycosteroids, and carotenoids.
According to a review of the anti-inflammatory properties of edible mushrooms published last March in the journal Food Chemistry, mushrooms of the Basidiomycota family display antioxidant, anticancer, and anti-inflammatory properties. Many mushrooms also contain the antioxidant mineral selenium.
Of all the botanicals, tea (Camellia sinensis) has one of the strongest associations with health, especially cardiovascular health. A recent study in the Journal of the American Heart Assn. (JAHA) reaffirms this. The study looked at the long-term effects of tea consumption and its influence on cardiovascular disease, especially regarding serum levels of high-density lipoprotein (HDL) cholesterol. HDL is one of a family of lipoproteins that move fats and cholesterol through the blood.
Lipoproteins are spheroidal with an outer layer of phospholipids, the fats that also make up membranes. Inside these spheres is a hydrophobic core that carries all fat-soluble substances, from cholesterol and triglycerides (fats) to fat-soluble vitamins and phytochemicals.
Higher levels of HDL cholesterol are generally associated with lower risk of CVD. With age, HDL cholesterol tends to decrease, thereby increasing the risk of a cardiovascular event. The JAHA study showed that tea consumption was associated with a lower age-related decrease in HDL and an 8% reduction in CVD risk.
Anti-inflammatory properties and health-protective benefits in ginger, turmeric, and garlic have been identified and studied for decades. Their medicinal use goes back thousands of years to the Egyptians, Babylonians, Greeks, Romans, and as an integral component of Indian Ayurveda and Traditional Chinese Medicine (commonly referred to as TCM).
Garlic is rich in sulphur compounds, responsible both for its pungent odor and many of its purported medicinal effects. It also contains the mineral selenium. Garlic is one of the most studied botanicals: Investigations of the health properties attributed to it have generated hundreds of publications in the last decade alone. In fact, a number of epidemiologic studies have linked garlic consumption specifically to reduced incidence of CVD.
Some of the mechanisms by which garlic works include lowering total cholesterol, altering the ratio of HDL to LDL cholesterol, and reducing the oxidation of LDLs, a risk factor in atherosclerosis. Some reports demonstrate a mild reduction in blood pressure and a decrease in platelet aggregation that can lead to dangerous clots.
Other medicinal plants reported to have antioxidant activity include hawthorn (Crataegus oxyacantha L.), grapes, blueberries, blackberries, cherries, elderberries, aronia berries, black currants, mulberries, and tea—all rich sources of procyanidins and anthocyanins.
Coenzyme Q10 (CoQ10) is a component found in every cell in the body. It is an essential part of the electron transport chain, the vital series of complexes imbedded in the inner mitochondrial membrane.
Mitochondria are like batteries for the cell, responsible for final stages of converting the food we eat into the energy that powers all of the body’s actions, both mental and physical. Cardiac muscles, which use a great deal of energy during their endless contractions, are rich in mitochondria, and thus in CoQ10.
Providing energy to hard-working cardiac muscles and their supporting tissues is only part of the heart benefits of CoQ10. It is also a powerful antioxidant that aids other antioxidants in their task of neutralizing tissue- and DNA-damaging compounds. CoQ10 helps to regenerate vitamin E so that it can continue its work.
CoQ10 is not considered an essential nutrient because the human body can make more CoQ10 than is needed to run the electron transport chain. However, age and battles with oxidizing agents tend to reduce CoQ10 production, causing a gradual decline in levels of the nutrient from about the mid-30s.
In addition, the cholesterol-lowering medications called “statins,” which work by inhibiting cholesterol synthesis, also inhibit the production of an important component of CoQ10. This can hinder the energy output of muscles, including heart muscles.
A four-year Swedish study conducted on 443 elderly subjects looked at the effects of supplementation with CoQ10 and selenium. The results showed a significantly reduced CVD mortality rate and improved cardiac function. Moreover, the effects seemed to persist long after the study had concluded.
After 12 years, significantly reduced CVD mortality could be seen in the supplemented individuals: Mortality was 28.1% in the active treatment group vs. 38.7% in the placebo group.
Reducing the risk of heart disease is in some ways a game of numbers, where several behaviors converge to either increase or decrease the odds of staying healthy. But while no single factor can provide an iron-clad guarantee, it is clear that proper nutrition from good foods and beverages tip the balance in the right direction.
Originally appeared in the November, 2018 issue of Prepared Foods as Take Heart.