Mediterranean Diet and Cardiovascular Diseases
Cardiovascular diseases remain a leading cause of morbidity and mortality worldwide. These conditions, including heart disease and stroke, are often linked to lifestyle factors, with diet playing a crucial role.
One diet that has gained significant attention for its potential in preventing and managing cardiovascular diseases is the Mediterranean diet. This article explores the Mediterranean diet and its impact on cardiovascular diseases (CVD).
We know that the Mediterranean diet is not just a diet but a way of life. It is inspired by the traditional dietary patterns of countries bordering the Mediterranean Sea, such as Greece, Italy, Spain, and about 20 others. This diet emphasizes whole, natural foods and is characterized by abundant fruits and vegetables, healthy fats, lean proteins, whole grains, nuts and seeds, and wine in moderation.
How Does the Mediterranean Diet Help Reduce the Risk of Cardiovascular Diseases?
The Mediterranean diet helps reduce the risk of cardiovascular diseases by combining its specific dietary components and overall lifestyle. Here are some key ways in which this diet is beneficial for heart health:
Healthy Fats: The Mediterranean diet is rich in healthy fats, primarily from olive oil, which is a rich source of monounsaturated fats. Numerous studies have demonstrated that adherence to the Mediterranean diet is associated with a lower risk of heart disease. These monounsaturated fats can help improve cholesterol levels by increasing HDL (good) cholesterol and reducing LDL (bad) cholesterol. This, in turn, lowers the risk of atherosclerosis (hardening of the arteries), which is a key factor in heart disease.
Antioxidants: Fruits and vegetables, as well as extra virgin olive oil especially early harvest olive oil, are abundant sources of antioxidants, such as vitamins C and E. These antioxidants help reduce oxidative stress and inflammation, which are associated with the development of cardiovascular diseases.
Omega-3 Fatty Acids: Fish, particularly fatty fish like salmon and mackerel, is a key protein source in the Mediterranean diet. It is rich in omega-3 fatty acids, which have anti-inflammatory properties and can lower the risk of arrhythmias (irregular heartbeats) and reduce the likelihood of blood clots.
Whole Grains: The diet emphasizes whole grains like whole wheat, brown rice, and oats, which provide fiber and various nutrients. Whole grains are always encouraged over refined grains. The fiber in whole grains can help lower cholesterol levels and improve blood sugar control, reducing the risk of heart disease and type 2 diabetes.
Nuts and Seeds: Nuts and seeds, such as pistachios, hazelnuts, almonds, and walnuts, as well as chia seeds, pumpkin seeds, and sesame seeds are part of the Mediterranean diet and are sources of healthy fats, fiber, and antioxidants. They can contribute to improved cholesterol levels and overall heart health.
Low in Red Meat: Red meat consumption is limited in the Mediterranean diet, and when consumed, it is typically lean and in smaller quantities. Reducing red meat intake can lower saturated fat and dietary cholesterol consumption, both of which are linked to heart disease.
Lean proteins: Fish and poultry are preferred over red meat, and legumes are often included as protein sources. Also, very infrequent consumption of red meat improves lipid profiles. The Mediterranean diet has been shown to improve lipid profiles by increasing HDL (good) cholesterol levels.
Moderate Wine Consumption: While not necessary for everyone, moderate consumption of red wine is a feature of the Mediterranean diet and provides antioxidants like resveratrol which is beneficial for the heart and blood vessels because of anti-inflammatory effects, antiplatelet activity, cholesterol and blood sugar regulation and other factors (we’ll talk about this a little later).
Reduced Sodium Intake: The Mediterranean diet typically includes less salt and processed foods, which can help in managing blood pressure, a major risk factor for heart disease.
Physical Activity: While not a dietary factor, the Mediterranean lifestyle often includes regular physical activity, which is beneficial for heart health. Exercise complements the diet in reducing the risk of cardiovascular diseases.
In summary, the Mediterranean diet's emphasis on whole, nutrient-dense foods, healthy fats, and antioxidants, along with reduced intake of processed and red meats, contributes to improved cholesterol profiles, lower inflammation, and better blood pressure control. This combination of factors makes it an effective dietary approach for reducing the risk of cardiovascular diseases.
Studies Connected with the Mediterranean Diet and Cardiovascular Diseases
Here are some important studies and findings some of which we have already talked about in detail:
Lyon Diet Heart Study (1999): This pioneering study (do not confuse it with the so-called “lion diet”, charlatan obscurantism that destroys the health of naive, illiterate “lions”!) demonstrated the benefits of the Mediterranean diet for heart health. It found that participants who followed a Mediterranean-style diet rich in olive oil and nuts had a significantly lower rate of heart attacks and other cardiovascular events compared to a control group following a low-fat diet.
PREDIMED Trial (2013): The PREDIMED study was a large, long-term, randomized controlled trial conducted in Spain. It showed that individuals assigned to a Mediterranean diet supplemented with extra-virgin olive oil or nuts had a reduced risk of major cardiovascular events. This study highlighted the potential of specific components of the Mediterranean diet in reducing CVD risk.
Dietary Approaches to Stop Hypertension (DASH): While not a Mediterranean diet study per se, the DASH study emphasizes many principles of the Mediterranean diet, such as high fruit and vegetable intake, whole grains, lean proteins, and reduced sodium. The DASH diet has been shown to lower blood pressure, a major risk factor for heart disease.
The Nurses' Health Study and Health Professionals Follow-up Study: These long-term observational studies have provided insights into the relationship between dietary patterns, including adherence to the Mediterranean diet, and cardiovascular health. They have shown that diets rich in whole grains, fruits, and vegetables are associated with lower cardiovascular risk.
Cardiovascular Health Study (CHS): The study has explored the impact of various dietary patterns on cardiovascular outcomes in older adults. It found that diets with characteristics similar to the Mediterranean diet were associated with a lower risk of heart disease and stroke.
EPIC (European Prospective Investigation into Cancer and Nutrition): This extensive study, involving multiple countries, has produced evidence supporting the protective effects of a Mediterranean-style diet against cardiovascular diseases, particularly among individuals with high adherence to the diet.
Moli-sani Study: Conducted in Italy, this study has examined the Mediterranean diet's impact on heart health. It found that greater adherence to the Mediterranean diet was associated with a reduced risk of major cardiovascular events and stroke.
These studies collectively provide strong evidence for the cardiovascular benefits of the Mediterranean diet. They underscore the importance of a diet rich in fruits, vegetables, whole grains, healthy fats, and lean proteins, along with reduced intake of processed foods and saturated fats, in reducing the risk of cardiovascular diseases. Adherence to these dietary patterns can contribute to a healthier heart and a lower risk of heart disease and stroke.
The Ancel Keys Study: The First Attempt to Find Out How the Mediterranean Diet is Connected to Cardiovascular Diseases
Ancel Keys (1904 – 2004) was an influential American physiologist and nutritionist known for his research on dietary patterns, including the Seven Countries Study, which significantly contributed to the understanding of the Mediterranean diet's potential benefits for heart health.
The Seven Countries Study, launched by Ancel Keys and his colleagues in 1958, was a landmark investigation that examined the relationships between diet, lifestyle, and cardiovascular diseases in Greece, Italy, Yugoslavia, Spain, South Africa, Japan, and Finland. Although it wasn't exclusively focused on the Mediterranean diet, it laid the groundwork for later studies on this dietary pattern.
Key findings from the Seven Countries Study included:
- Dietary Patterns: The study highlighted the dietary habits of different regions, particularly the Mediterranean countries (e.g., Greece and Italy), where a traditional diet rich in fruits, vegetables, whole grains, olive oil, and fish was associated with lower rates of heart disease.
- Saturated Fat and Cholesterol: The study suggested that diets high in saturated fat and cholesterol, often found in Western countries, were linked to higher rates of heart disease. In contrast, Mediterranean diets, which were lower in saturated fat, appeared to be protective.
- Heart Disease Rates: The Seven Countries Study provided early evidence that heart disease rates were significantly lower in regions where people adhered to a Mediterranean-style diet. This finding raised awareness of the potential health benefits of this dietary pattern.
While the study did not directly define the Mediterranean diet as we know it today, it played a pivotal role in highlighting the significance of dietary patterns in cardiovascular health. Subsequent research, including the PREDIMED study and other investigations mentioned earlier, built upon these insights and further explored the Mediterranean diet's specific components and benefits.
Ancel Keys' work remains a foundational piece in the field of nutrition and cardiovascular health, and it contributed to the recognition of the Mediterranean diet as a heart-healthy dietary pattern.
Other Mediterranean Diet Benefits Reducing Risk of Cardiovascular Diseases
In addition to its direct effect on reducing the risk of cardiovascular diseases, the Mediterranean diet has two more important benefits (here we’ll go a little aside and dwell on these two points in more detail):
- Weight Management: The Mediterranean diet is associated with weight management and lower obesity rates due to its focus on whole, nutrient-dense foods. Maintaining a healthy weight is essential for heart health since obesity is a significant risk factor for cardiovascular diseases.
How Does Weight Management Help Prevent CVD?
Weight management plays a crucial role in preventing cardiovascular diseases (CVD). Maintaining a healthy weight contributes to heart health in several ways:
Blood Pressure Control: Excess body weight, especially when it leads to obesity, is a significant risk factor for high blood pressure (hypertension). High blood pressure puts extra strain on the heart and arteries, increasing the risk of atherosclerosis (hardening and narrowing of the arteries) and other heart-related problems. Managing weight can help reduce blood pressure and lower the risk of CVD.
Improved Cholesterol Profile: Weight management can lead to improvements in cholesterol levels. Losing excess weight, particularly abdominal fat, tends to lower levels of low-density lipoprotein (LDL or "bad" cholesterol) and triglycerides while increasing high-density lipoprotein (HDL or "good" cholesterol). A healthier cholesterol profile reduces the risk of atherosclerosis and related cardiovascular issues.
Better Blood Sugar Control: Maintaining a healthy weight helps regulate blood sugar levels. Obesity and excessive weight gain are major risk factors for type 2 diabetes, a condition that significantly increases the risk of CVD. By controlling weight and promoting insulin sensitivity, the risk of diabetes and related heart problems is reduced.
Reduced Inflammation: Obesity is associated with chronic inflammation, which can damage blood vessels and increase the risk of atherosclerosis. Weight management can help reduce inflammation markers and lower the overall inflammatory burden on the cardiovascular system.
Prevention of Atherosclerosis: Excess body fat, especially abdominal or visceral fat, is linked to the development of atherosclerosis. Losing weight can slow the progression of plaque buildup in the arteries and reduce the risk of heart attacks and strokes.
Reduced Strain on the Heart: Carrying excess weight puts extra strain on the heart, leading to conditions like heart failure. Weight management can alleviate this strain, improving heart function and reducing the risk of heart failure.
Sleep Apnea Prevention: Obesity is a major risk factor for sleep apnea, a condition characterized by disrupted breathing during sleep. Sleep apnea is associated with an increased risk of hypertension and other cardiovascular problems. Weight loss can alleviate or prevent sleep apnea, reducing related cardiovascular risks.
Enhanced Endothelial Function: Weight loss can improve the function of the endothelium, the inner lining of blood vessels. Healthy endothelial function is crucial for maintaining blood vessel flexibility and preventing endothelial dysfunction, which can lead to atherosclerosis and other cardiovascular issues.
The WHO (World Health Organization) acceleration plan to stop obesity is designed to stimulate and support multisectoral country-level action across the globe. Drawing on policies that are already tried and tested and based on implementation and delivery science, the plan offers the prospect of a step change in delivery and impact in the effort to tackle the growing crisis of obesity.
In summary, weight management is an essential component of cardiovascular disease prevention. It reduces the risk of hypertension, abnormal cholesterol levels, diabetes, atherosclerosis, inflammation, and other risk factors that can lead to heart disease. A balanced diet and regular physical activity are typically recommended for achieving and maintaining a healthy weight and overall heart health. Additionally, it's important to consult with healthcare professionals for personalized guidance on weight management and cardiovascular disease prevention.
- Diabetes Prevention: Lots of studies suggest that the Mediterranean diet may help in preventing type 2 diabetes.
Why is type 2 diabetes a significant risk factor for CVD?
Because it directly and indirectly contributes to the development and progression of heart and vascular problems. Here are several key reasons why type 2 diabetes is associated with an increased risk of CVD:
Insulin Resistance: In type 2 diabetes, the body's cells become resistant to the action of insulin, a hormone that helps regulate blood sugar (glucose) levels. As a result, the body needs more insulin to keep blood sugar in check. This insulin resistance is linked to a range of cardiovascular risk factors.
Hyperglycemia: Elevated blood sugar levels, known as hyperglycemia, are a hallmark of diabetes. Prolonged periods of high blood sugar can lead to damage of the blood vessels, which is a major contributor to atherosclerosis (narrowing and hardening of the arteries), a key risk factor for CVD.
Dyslipidemia: Type 2 diabetes is often associated with dyslipidemia, an abnormal lipid profile characterized by high levels of triglycerides, low levels of high-density lipoprotein (HDL or "good" cholesterol), and sometimes high levels of low-density lipoprotein (LDL or "bad" cholesterol). This lipid profile is a major risk factor for atherosclerosis and CVD.
Hypertension: High blood pressure is common in individuals with type 2 diabetes. Hypertension increases the workload on the heart and can lead to heart muscle thickening and heart failure, both of which are associated with an increased risk of CVD.
Obesity: Obesity is a significant risk factor for both type 2 diabetes and CVD. Excess body weight, particularly abdominal fat, can lead to insulin resistance, inflammation, and atherosclerosis.
Inflammation: Chronic inflammation is more common in individuals with diabetes. Inflammation can damage blood vessels, promoting the development of atherosclerosis and increasing the risk of heart attacks and strokes.
Prothrombotic State: Diabetes can create a prothrombotic (blood clot-promoting) state. This increases the risk of clot formation in the arteries, which can lead to coronary artery disease and stroke.
Microvascular Complications: Diabetes can lead to microvascular complications, affecting small blood vessels in organs like the eyes (diabetic retinopathy), kidneys (diabetic nephropathy), and nerves (diabetic neuropathy). These complications, while not directly related to the cardiovascular system, are associated with an increased risk of CVD.
Heart Muscle Dysfunction: Diabetes can affect the heart muscle, leading to a condition known as diabetic cardiomyopathy. This condition impairs the heart's ability to pump blood effectively and can result in heart failure.
Higher CVD Mortality: Individuals with diabetes are at higher risk of CVD-related mortality, meaning they are more likely to die from cardiovascular events such as heart attacks and strokes.
Unhealthy eating habits and sedentary lifestyles associated with urbanization are common factors contributing to the development of type 2 diabetes. There is overwhelming evidence from studies in the USA, Finland, China, India, and Japan that lifestyle changes (achieving a healthy body weight and moderate physical activity) can help prevent the development of type 2 diabetes in people at risk.
To mitigate the increased risk of CVD associated with type 2 diabetes, it is essential for individuals with diabetes to manage their blood sugar levels effectively, control their blood pressure, maintain a healthy weight, and address other cardiovascular risk factors through lifestyle changes and, in some cases, medication. Regular monitoring, close medical supervision, and adherence to a heart-healthy lifestyle are crucial in managing the intersection of type 2 diabetes and cardiovascular disease.
How Is Red Meat Connected with Cardiovascular Diseases?
Consumption of red meat, particularly when it's high in saturated fat, has been associated with an increased risk of CVD. Several factors contribute to this connection:
Saturated Fat: Red meat, especially fatty cuts like steak and processed meats (e.g., sausages and bacon), is a significant source of saturated fat. A diet high in saturated fat can raise levels of LDL (low-density lipoprotein) cholesterol, often referred to as "bad" cholesterol. Elevated LDL cholesterol is a known risk factor for atherosclerosis, which is the buildup of plaque in the arteries, narrowing them and increasing the risk of heart disease.
Heme Iron: Red meat contains heme iron, a type of iron that is more readily absorbed by the body compared to non-heme iron found in plant-based foods. Excessive iron intake, particularly from heme iron, has been associated with an increased risk of CVD because it can lead to oxidative stress, inflammation, and damage to blood vessels.
Advanced Glycation End Products (AGEs): Cooking red meat at high temperatures (e.g., grilling, frying) can lead to the formation of advanced glycation end products (AGEs). AGEs are compounds that have been linked to inflammation and oxidative stress, both of which can contribute to the development of cardiovascular diseases.
Processed Meats: Processed red meats, such as hot dogs, sausages, and deli meats, often contain high levels of sodium and preservatives. Excessive sodium intake can raise blood pressure, increasing the risk of hypertension, which is a significant risk factor for heart disease.
Pro-Inflammatory Compounds: Some compounds found in red meat, such as Neu5Gc, have been associated with an increased risk of inflammation. Chronic inflammation is believed to play a role in the development of atherosclerosis and other cardiovascular conditions.
It's important to note that not all studies have found a strong connection between red meat consumption and heart disease, and some research suggests that lean cuts of red meat may not carry the same risks as processed or fatty cuts. Additionally, individual factors, including genetics, overall dietary patterns, and lifestyle, can influence how red meat consumption affects an individual's cardiovascular risk.
In light of these associations, many health authorities recommend moderating red meat intake and opting for lean cuts when consumed. A heart-healthy diet often emphasizes lean protein sources like fish, poultry, legumes, and plant-based proteins, while reducing the consumption of red and processed meats high in saturated fat and sodium. A balanced diet that includes a variety of foods and emphasizes fruits, vegetables, whole grains, and healthy fats can help lower the risk of cardiovascular diseases.
How Moderate Wine Consumption Can Help Reduce Risk of Cardiovascular Diseases?
Well, for many of us, it was sad to learn that eating a lot of red meat prevents us from being healthy. So enough about the sad stuff, let's talk about wine. We know that wine contains an important component: resveratrol. What is it and why is it that important?
Resveratrol is a natural compound found in various plants, including grapes, red wine, and some berries, and it has gained attention for its potential benefits for heart health and blood vessels. While the exact mechanisms are still being studied, there are several reasons why resveratrol is considered beneficial for the heart and blood vessels:
Antioxidant Properties: Resveratrol is a potent antioxidant. Antioxidants help protect the body's cells, including those in the heart and blood vessels, from damage caused by free radicals and oxidative stress. By reducing oxidative stress, resveratrol can help prevent inflammation and damage to blood vessel walls, which are early steps in the development of cardiovascular diseases.
Anti-Inflammatory Effects: Resveratrol has anti-inflammatory properties. Chronic inflammation is linked to the development and progression of atherosclerosis (hardening and narrowing of the arteries), which is a primary cause of heart disease. By reducing inflammation, resveratrol may help maintain healthy blood vessels.
Improvement in Endothelial Function: The endothelium is the inner lining of blood vessels. Resveratrol has been shown to improve endothelial function by enhancing the production of nitric oxide, a molecule that helps relax and dilate blood vessels. This improved endothelial function can lead to better blood flow and lower blood pressure, reducing the risk of heart disease.
Antiplatelet Activity: Resveratrol may help prevent excessive blood clotting by inhibiting the activation of platelets. This can reduce the risk of clot formation in the arteries, which can lead to heart attacks and strokes.
Cholesterol Regulation: Some studies suggest that resveratrol can help regulate cholesterol levels, particularly by increasing high-density lipoprotein (HDL or "good" cholesterol) and reducing low-density lipoprotein (LDL or "bad" cholesterol). This balance is important for heart health.
Blood Sugar Regulation: Resveratrol may have a positive effect on blood sugar regulation and insulin sensitivity. Maintaining stable blood sugar levels is important in reducing the risk of type 2 diabetes, a significant risk factor for heart disease.
Anti-Aging Effects: While not directly related to cardiovascular health, resveratrol has been studied for its potential anti-aging effects. Some researchers believe that the compound's ability to combat age-related changes in cells and tissues may indirectly benefit heart and vascular health.
It's important to note that while studies have shown the potential benefits of resveratrol in animal and cell-based research, the effects in humans are still being explored. Moreover, the concentration of resveratrol in foods like red wine is relatively low, so it may not be practical to obtain therapeutic levels of resveratrol from dietary sources alone. As a result, resveratrol supplements have been developed, but their efficacy and safety are subjects of ongoing investigation. It's always advisable to consult with a healthcare professional before starting any supplementation regimen to ensure it's appropriate for your specific health needs.
The Mediterranean diet is not only a delicious way to eat but also a potent weapon against cardiovascular diseases. Its emphasis on whole, unprocessed foods, healthy fats, and abundant fruits and vegetables provides numerous health benefits, particularly in reducing the risk of heart disease.
Incorporating the principles of the Mediterranean diet into one's lifestyle may lead to better cardiovascular health and an overall healthier life. However, it's essential to remember that diet is just one component of heart health, and other lifestyle factors like regular physical activity and not smoking play vital roles as well.
One more thing about the Mediterranean diet and cardiovascular diseases: In general, guys, this is very serious. And the less we notice it, the more serious and dangerous it is. Cardiovascular diseases claim tens of millions of lives every year, and in most cases, people who died from the “silent killer” (as CVD is called) simply ignored it because there were no obvious symptoms.
Scientific research confirms that consistent adherence to the Mediterranean diet greatly reduces your risk of dying from CVD. This diet does not require Herculean efforts from you, so enjoy your Mediterranean lifestyle and take care of yourself!