Abstract
It should be noted that among the most common diseases we have nowadays, issues on cardiovascular diseases concern us the most. These diseases are directly interconnected with other health problems such as obesity, high blood pressure, heart failure, etc. And with this, it is important to reiterate the importance of maintaining a good and proper diet coupled with a healthy lifestyle.
There is an increasing rate of cardiovascular diseases affected people in the UK. Reports revealed that this prevalence is caused by inappropriate diet and sedentary lifestyle that the UK people now have. This paper provides an insight into how important proper diet and nutrition are in the prevention of cardiovascular disease. Specific nutritional requirements of the body are highlighted and how it assists the body systems and organs. Some of the most highlighted diet-related information highlighted in this paper is the roles played by the dietary fats (saturated fat, MUFA, PUFA, trans-fat, carbohydrates, dietary Fibres, anti-oxidants, and much more in the prevention of the onset of diseases such as CVD.
Introduction
Background
Cardiovascular disease is the major cause of death and disability in today’s society. In the year 1997 alone, nearly 1 million people are pronounced dying year of heart disease and stroke in the United States, and an estimated $150 billion will be spent on the care of these patients (American Heart Association, 1996).
More so, research reveals that cardiovascular diseases are prevalent in the aging population and are the main cause of death even in the UK countries, e.g. in Finland cardiovascular diseases cause nearly half of all deaths (Statistics, Finland, 2002). Moreover, they still belong to the most common reasons for disability pension after mental and musculoskeletal disorders. The primary cardiovascular risk factors, such as hypertension, high cholesterol levels, diabetes, overweight, smoking, and physical inactivity have been well studied and recognized (Renaud, 2001).
The reason for the appearance
But, despite these frightening statistics related to cardiovascular diseases, physicians and other medical health providers are firmed in saying that cardiovascular disease, i.e., primarily coronary heart disease, stroke, and peripheral vascular disease, are potentially preventable diseases. After many years of epidemiological, animal experimental, and clinical trials, the primary determinants of cardiovascular disease have been identified, as well as the efficacy of specific interventions.
Cardiovascular diseases are now increasing in less urbanized, developed populations across the world, as their lifestyles change to a so-called “western-style”, with increasing consumption of dietary saturated fat and cholesterol, cigarette smoking, salt, decreased physical activity and obesity, and the rise in risk factors that lead to cardiovascular disease (Renaud, 2001).
UK Statistics
As stated above, the prevalence of cardiovascular disease in the UK is frightening. There are hundreds of credible reports providing new information on the prevalence of cardiovascular disease and its risk factors: alcohol consumption; smoking; poor diet; lack of physical exercise; obesity and high blood pressure. Some of the worth noting numbers include (Colhoun H and Prescott-Clarke, 1996):
- The overall prevalence of cardiovascular disease in the UK decreased between 1993 and 1994 and increased again in 1998 with an overall prevalence of IHD or stroke increased between 1994 and 1998. In men, it rose from 7.1 to 8.5% of the total population, while the increase for women was from 5.2 to 6.2%.
- There is an equal proportion of men vs. women with cardiovascular disease (CVD) conditions (angina, heart attack, stroke, heart murmur, and abnormal heart rhythm, other heart trouble, diabetes, or high blood pressure). Excluding those with high blood pressure, because men tend to be affected more by this illness than women.
- It also evident that in the UK, there was a socio-economic slope in the prevalence of CVD and IHD. The age-standardized prevalence of IHD was lower in men in lower social class compared to higher social status and the same thing goes to women.
- In both sexes, the prevalence of high fat and low fiber intake was higher in manual social classes and in is lower-income households.
- There was a marked decline in men’s physical activity with increasing age and further probing reveals that women’s activity levels were much lower than men’s in the younger age groups
- The age-standardized proportion of men meeting the guidelines for physical activity was considerably higher in manual than non-manual social classes
The Role of Diet
As it is important to be vigilant against cardiovascular diseases that can kill most of us, it is also very necessary to know more about how can the upsurge of cardiovascular diseases be prevented. And with this came the idea of diet and nutrition.
Today most of us dwell in mechanized urban settings, leading largely sedentary lives and eating a highly processed synthetic diet. As a result, two-thirds of Americans are overweight or obese. The lifetime incidence of hypertension is an astounding 90%, and the metabolic syndrome is present in up to 40% of middle-aged American adults. Cardiovascular disease remains the number 1 cause of death, accounting for 41% of all fatalities, and the prevalence of heart disease in the United States is projected to double during the next 50 years (Macaulay, et. al., 1999). Despite remarkable pharmacological and technological advances, the pandemic of cardiovascular disease continues.
At least for today, the genes we are born with are those that we will live and die with. Thus, the most practical solution for reducing the incidence of cardiovascular diseases such as atherosclerosis is to realign our current maladaptive diet and lifestyle to simulate the milieu for which we are genetically designed (Flegal, et. al, 2002).
Living organisms thrive best in the milieu and on the diet to which they were evolutionarily adapted; this is a fundamental axiom of biology. All of the food consumed daily by our ancient ancestors had to be foraged or hunted by wild plants and animals in their natural world. In many respects, that Paleolithic world is gone forever, but insights gained from a wide array of disciplines are providing a clear picture of the ideal diet and lifestyle for humans. The hunter-gatherer mode of life became extinct in its purely non-westernized form in the 20th century (Macaulay, et. al., 1999). At the beginning of the 21st century, we are the first generation to have the genetic and scientific understanding to allow us to reconstruct the essence of this lifestyle and the means to afford it (Flegal, et. al, 2002).
Historical and archaeological evidence shows hunter-gatherers generally to be lean, fit, and largely free from signs and symptoms of chronic diseases. When hunter-gatherer societies transitioned to an agricultural grain-based diet, their general health deteriorated. Average adult height was substantially shorter for both men and women who consumed cereals and starches compared with their hunter-gatherer ancestors who consumed lean meats, fruits, and vegetables (Ford, et. al., 2002).
Furthermore, studies of bones and teeth reveal that populations who changed to a grain-based diet had shorter life spans, higher childhood mortality, and a higher incidence of osteoporosis, rickets, and various other minerals- and vitamin deficiency diseases. When former hunter-gatherers adopt Western lifestyles, obesity, type 2 diabetes, atherosclerosis, and other diseases of civilization become commonplace (Daniel, et. al., 1999).
Perhaps no scientific topic has generated more controversy and confusion in recent times than the question of the ideal human diet. Medical experts espouse divergent views of human nutrition with evangelical zeal, each citing scientific data to validate their respective contradictory conclusions. This confusing dialogue is epitomized by the Atkins vs. Ornish debate. The Atkins diet includes high protein, high saturated fat, and avoidance of nearly all carbohydrates (Atkins, 1998). In contrast, the Ornish diet consists of 80% carbohydrates and minimized consumption of all animal protein fats (Ornish, 1990). Proponents of both diets insist theirs is the answer to the American epidemics of obesity and cardiovascular disease; however, the advice for these diets is mutually exclusive and opposed (Daniel, et. al., 1999).
In truth, the ideal diet is neither of these extremes nor what many medical professionals now promote. In a recently published large review of approximately 150 studies on the link between diet and cardiovascular health, the authors concluded that 3 major dietary approaches have emerged as the most effective in preventing cardiovascular events (Ford, et. al., 2002):
- replacing saturated and trans-fats with monounsaturated and polyunsaturated fats
- increasing consumption of omega-3 ([omega]-3) fats from either fish or plant sources such as nuts
- eating a diet high in various fruits, vegetables, nuts, and whole grains and avoiding foods with a high glycemic load (a large amount of quickly digestible carbohydrates).
Despite common misperceptions, it was found out that there is no strong evidence for a link between the risk of cardiovascular disease and intake of meat, cholesterol, or total fat.
These broad characteristics are consistent with the diet that Paleolithic humans evolved eating. This is the diet that our hunter-gatherer ancestors thrived on until the advent of the agricultural revolution. Through the millennia, our genome and physiology became adapted to this diet. Of course, this diet varied by paleontological period, geographic location, season, and culture, but many characteristics remained consistent until recent times (Daniel, et. al., 1999).
Throughout most of human history, food consumption (energy intake) was obligatorily linked to food acquisition (energy output). Accordingly, our ancient ancestors expended more energy finding and obtaining food calories than do typical sedentary, westernized citizens for whom there is virtually no connection between energy intake and energy expenditure (Daniel, et. al., 1999).
Our cravings for calorie-dense foods, such as fats, sweets, and starches, are legacies of our Paleolithic ancestors, who sought these foods because they conferred positive survival value in an environment in which these food types were scarce. These cravings betray us in our modern world, where calorie-dense foods are abundant and inexpensive, and most people die of caloric excess manifested as obesity, metabolic syndrome, hypertension, and cardiovascular disease (Daniel, et. al., 1999).
Compounding the issue is the fact that our genome became adapted to an environment in which caloric intake was often sporadic and sometimes inadequate. This promoted efficient energy use and storage commonly referred to as the thrifty gene hypothesis. Although this genetic adaptation (which results in the storage of excess calories as intra-abdominal fat) provides a survival advantage in an environment of scarcity, it becomes a liability in the setting of long-term excessive caloric intake (Joshipura, et. al., 2001).
Although the key to weight loss is simply the daily consumption of fewer calories than are expended, it is easier to moderate caloric intake in a diet that has adequate quantities of protein and fat because of superior satiety compared with a high-carbohydrate, low-fat diet. This strategy in part accounts for the success of the Atkins diet in inducing weight loss, but its high levels of saturated fat, low levels of antioxidants, and net metabolic acidosis, which may promote osteoporosis and atherosclerosis, make this a suboptimal eating style (Ford, et. al., 2002).
A growing consensus indicates that a diet containing moderate amounts of beneficial fat and protein in addition to carbohydrates consisting exclusively of low-glycemic-load foods (non-starchy vegetables and fruits) in conjunction with daily exercise is the most effective way to achieve and maintain ideal body weight and prevent cardiovascular disease. This approach was the eating pattern and lifestyle of prehistoric humans (Joshipura, et. al., 2001).
The polyunsaturated fats are classified as [omega]-6 (generally pro-inflammatory) and [omega]-3 (anti-inflammatory with several other inherent cardioprotective effects), [omega]-3 Fats were abundant in the diet of our Paleolithic ancestors. In the natural world, the broad base of the food chain is composed of ubiquitous algae in the sea and grasses and leaves on land.
The small amount of fat in algae, grasses, and leaves is rich in [omega]-3 fatty acids, which become more concentrated in larger animals up through both the land and marine food chains, especially in fish and larger grazing animals. Today, meat from domesticated animals is low in [omega]-3 fats because these animals are generally grain-fed or corn-fed rather than grass-fed. This and other issues have resulted in a much lower intake of [omega]-3 fats today compared with our remote ancestors (Ford, et. al., 2002).
The correction of this [omega]-3 deficiency in the modern diet is a key step to improving the cardiovascular risk in our population. Two randomized trials, the Lyon Diet Heart Study, which involved 600 post-infarction patients, and the Indo-Mediterranean Diet Heart Study, which involved 1000 coronary heart disease patients, evaluated a standard low-fat American Heart Association diet vs. the traditional Mediterranean. The patients on the Mediterranean diet rich in [omega]-3 and monounsaturated fats, fruits, vegetables, legumes, and nuts experienced 50% to 70% reductions in risk of cardiovascular events during long-term follow-up.
Monounsaturated Fats
Monounsaturated fats made up approximately half of the total fat in the diets of most hunter-gatherers. Monounsaturated fats reduce cardiovascular risk, especially when substituted for easily digestible starches and sugars. Nuts are a valuable source of monounsaturated fats and are cardio-protective in at least 6 epidemiological studies. Our hunter-gatherer ancestors relied on nuts as an easily accessible source of calorie-dense, highly nutritious food that was often available in non-summer months. The calories in nuts typically are 80% from fat, but most of this is in the form of healthy monounsaturated and polyunsaturated fatty acids.
Epidemiological studies show that frequent nut consumption (5 or more times per week) is associated with up to a 50% reduction in risk of myocardial infarction compared with the risk of people who rarely or never eat nuts. Other studies show that nut consumption reduces the risk of developing type 2 diabetes, lowers the atherogenic low-density lipoprotein (LDL) cholesterol level without lowering the high-density lipoprotein (HDL) level,40 and provides plant-based protein and other potentially cardioprotective nutrients such as vitamin E, folate, magnesium, copper, zinc, and selenium. Because of their high levels of fiber, protein, and fat, nuts also provide better and longer-lasting satiety compared with high-glycemic-load snack foods typically consumed today.
Oleic acid is the major monounsaturated fat in our diets and is found in meats, nuts, avocados, dark chocolate, and olive oil. Although some of these foods were not part of the ancient ancestral diet, they can improve the cardiovascular risk profile when substituted for sugar, starches, trans-fats, and saturated fats that are prevalent in the modern diet. Studies suggest that replacing saturated fat with monounsaturated fat would result in a 30% reduction in risk, or 3 times the risk reduction achieved by replacing saturated fat with carbohydrates.
Carbohydrates
Many current vegetarians would be more appropriately labeled “breatharians.” Modern vegetarian diets often rely heavily on processed carbohydrates such as white rice, potatoes, and white flour and sugars. The South Asian paradox refers to the relatively high prevalence of coronary heart disease despite low levels of LDL cholesterol and low prevalence of obesity in urban vegetarians from India who consume a diet high in refined carbohydrates.
In westernized societies, sugar intake has increased substantially during the past 2 centuries. A recent study showed that a high-glycemic-load diet is the most important dietary predictor of HDL level (as an inverse relationship). A high-glycemic-load diet predisposes a person to metabolic syndrome and cardiovascular disease and is one of the most atherogenic features of our modern eating pattern (Cordain 2002).
Meat
It should be noted that although increased meat consumption in Western diets has been associated with increased cardiovascular risk, hunter-gatherer societies were relatively free of the signs and symptoms of cardiovascular disease. The flesh of wild game is typically about 2% to 4% fat by weight and contains relatively high levels of monounsaturated and [omega]-3 fats compared with fatty grain-produced domestic meats, which can contain 20% to 25% fat by weight, much of it in the form of saturated fat (Cordain 2002).
Wild game meat is not widely accessible today, and many people do not prefer the “game” taste, which is at least in part conferred by a higher [omega]-3 content and by aromatic oils from plant foods consumed by the herbivore. The modern-day alternative is to choose animal protein sources that are low in saturated fat, such as skinless poultry, fish, eggs (especially high-[omega]-3 varieties), and lean cuts of red meat with visible fat trimmed (Renaud, 2001).
This generalized the idea that it is not the amount of meat eaten but rather the composition of the meat and cooking methods that determine the health effects of this food. Accumulating scientific evidence indicates that meat consumption is not a risk for cardiovascular disease, but instead, the risk is secondary to high levels of saturated fat typically found in the meat of most modern domesticated animals. Diets high in lean protein can improve lipid profiles and overall health, especially if care is taken to trim any visible fat from the meats and to allow the fat to drain when cooking (Renaud, 2001).
Lean animal protein eaten at regular intervals (with each meal) improves satiety levels, increases dietary thermogenesis, improves insulin sensitivity, and thereby facilitates weight loss while providing many essential nutrients. However, cooking red meats at high temperatures produces charring and high levels of heterocyclic amines, which have been implicated in the risk of gastrointestinal and prostate cancers. Highly salted and preserved meats may also contain carcinogens. Lean, fresh meat cooked appropriately is a healthy and beneficial component of a varied diet, especially in conjunction with a high intake of vegetables and fruits (Cordain 2002).
Trans-Fatty Acids
Trans-fatty acids are found in small quantities in the fat tissues of all ruminant animals. However, in recent decades, the intake of trans-fatty acids has increased markedly because of their ubiquitous presence in commercially prepared foods (Renaud, 2001). Trans-fatty acids are synthesized when hydrogen is applied to edible oils under high pressure and temperature in the presence of a catalyst.
Hydrogenation of the edible oils is typically done in the prepared food industry to prolong shelf-life in commercial baked goods such as cookies, crackers, donuts, croissants, and processed snack foods. Trans-fatty acids are also found in shortenings, most margarine, and deep-fried foods, and recently in many brands of commercially available canola oils.67 Trans-fats lower HDL levels, increase LDL levels, and increase the risk of both cardiovascular disease and cancer (Cordain 2002).
Studies indicate that replacing trans-faulty acids (typically 2% of total daily calories in the American diet) with the same amount of natural unsaturated fatty acids would result in a large (50%) decrease in the risk of coronary heart disease.
Fibers
Based on a series of studies, a conclusion has been made that fibers really help a lot in the prevention and even in some form of treatments of cardiovascular diseases. Pairing niacin or psyllium fiber with a statin can enhance the regimen’s ability to reduce a patient’s cardiovascular risk factors, according to the annual scientific sessions of the American Heart Association (Zoler, 2005). Such information resulted in a more positive conclusion that treatment with 3.6 g/day soluble fiber will have the same incremental impact on lowering LDL cholesterol as did doubling a patient’s dosage of simvastatin from 10 mg/day to 20 mg/day. In addition, the psyllium fiber dosage used was very well tolerated. In fact, most physicians who treat high cholesterol levels have heard of the benefits of using dietary fiber. These results document the effect.
Fruits, Vegetables, and Anti-Oxidants
Several studies have suggested that there is a strong link between dietary phytochemical intake and a reduced risk for cardiovascular disease. Dietary flavonoids have been inversely correlated with mortality from coronary artery disease, plasma total cholesterol, and low-density lipoprotein (LDL). Oxidized LDL has been proposed as an atherogenic factor in heart disease, promoting cholesterol ester accumulation and foam cell formation.
Dietary antioxidants from fruits and vegetables get incorporated into LDL and become oxidized themselves, thus preventing the oxidation of polyunsaturated fatty acids. Phyto-chemicals also reduce platelet aggregation, modulate cholesterol synthesis and absorption, and reduce blood pressure. Systemic inflammation may also be a critical factor in cardiovascular disease. C-reactive protein, an inflammatory marker, may be a stronger predictor of cardiovascular disease than LDL cholesterol, and the anti-inflammatory activity of phytochemicals may play an important role in the health of the heart (Sanchez, et.al., 2000).
Beverages
Recent data suggest that generous water intake, 5 or more glasses daily, is associated with a lower risk of coronary heart disease. This may be simply a function of the fact that water, when consumed frequently, displaces calorie-dense beverages such as sugared sodas from the diet. Or it may be that water provides adequate hydration and reduces blood viscosity better than other commonly ingested drinks. In any event, water is the beverage we are adapted to drink, and evidence suggests that it should remain the principal fluid we drink (Cordain 2002).
Sugared sodas are the predominant beverage consumed in America today. These are calorie-dense, nutritionally barren drinks that have contributed to the rise in obesity and insulin resistance. Generally, fruit juices are also high in sugar, and thus it is preferable to eat the whole fruit, which provides fiber and a lower glycemic load (Cordain 2002).
The Course of Action
With all facts and figures presented, it can be realized that in order to somewhat prevent today’s generation from the burden of cardiovascular diseases, it is the people’s responsibility to be conscious enough with the kinds of food to take and the kind of lifestyle to participate with.
It is strongly suggested to understand the importance of maintaining a good and proper diet coupled with a healthy lifestyle.
That is what all people must do in order to keep themselves away from various cardiovascular illnesses. And this is also what should be shared with other people, including friends and companions, in the hope that that they too shall pass this along so as to somehow help other people too.
Indeed maintaining proper diet and exercise will help a lot in preventing oneself from getting any cardiovascular illnesses. Nowadays, there is an increased prominence on healthy living. Living healthy is to achieve ideal body weight or figure through exercise and diet. Exercise and diet is an effective strategy for losing bodyweight than dieting alone. Most people think that dieting for a certain number of days would lose weight. However, losing weight for a short time would turn the body bingeing for more food.
Eating and exercise habits determine whether the body loses or gains weight. This uncovers how many calories take in and use up. To lose body weight, there is a need to control the number of calories through obtaining a balanced diet and increase the number of calories burned through exercise (Diet and Exercise, 1998). It is also recommended to consult the physician before starting any reduce-calorie diet and exercise program, especially for people who have a history of health problems such as cardiovascular disease or other unknown conditions, pregnant or lactating mothers (Diet and Exercise, 1998)
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