Vegan Diets: Thinning Blood Or Health Myth?

A vegan diet is often associated with improved health outcomes, including lower blood pressure and reduced risk of heart disease. However, some people have raised concerns about the potential impact of a vegan diet on blood viscosity and clotting. There are reports of individuals experiencing increased bleeding after adopting a vegan diet, leading to questions about whether veganism can thin the blood. While a vegan diet may not directly thin the blood, it can affect certain factors that influence blood viscosity and clotting. For example, a vegan diet can lead to lower levels of vitamin K, which is involved in blood clotting. Additionally, certain supplements commonly used by vegans, such as omega-3 fatty acids, can act as blood thinners. Overall, while a vegan diet may not directly thin the blood, it can impact factors that influence blood viscosity and clotting, and it is important for individuals to be aware of these potential effects and consult with healthcare professionals to ensure their diet is meeting their individual needs.

A vegan diet may lower cholesterol and reduce heart disease risk

A vegan diet can be a healthy way to improve cardiovascular health and lower cholesterol levels. Research suggests that a plant-based diet can effectively lower both systolic and diastolic blood pressure. This is supported by numerous studies, including the Adventist Health Study-2, which found that vegans had significantly lower blood pressure and a lower prevalence of hypertension compared to non-vegetarians.

A vegan diet can also positively impact cholesterol levels. One individual who followed a vegan diet for 30 days reported a significant reduction in their total cholesterol to HDL ("good") cholesterol ratio, which lowered their risk of heart disease. This is supported by larger studies, such as the Coronary Artery Risk Development in Young Adults (CARDIA) study, which found an inverse relationship between plant-based food consumption and blood pressure.

In addition to lowering cholesterol and blood pressure, a vegan diet may also reduce the risk of other cardiovascular issues. For example, a study published in the Journal of the Academy of Nutrition and Dietetics found that a vegan diet increased metabolism and improved weight and body composition, which are also risk factors for heart disease.

However, it is important to note that a vegan diet may be lacking in certain key nutrients, such as iron, zinc, vitamin B12, and omega-3 fatty acids. Therefore, it is important for vegans to ensure they are getting adequate amounts of these nutrients through supplements or fortified foods.

Vegan diets can be low in nutrients like iron, zinc, B12, and omega-3s

A vegan diet can be low in nutrients like iron, zinc, B12, and omega-3s. While a balanced vegetarian diet can provide enough protein, this isn't always the case when it comes to fat and fatty acids.

Iron is important for the body as it helps carry oxygen in the blood and transport it throughout the body. Zinc is a nutrient that people need for their immune system to function optimally. It plays a vital role in protein synthesis and helps heal wounds. Vitamin B12 is necessary for maintaining healthy nerve cells and blood cells. Omega-3 fatty acids are essential for brain function and heart health.

Vegans tend to have elevated blood levels of homocysteine and decreased levels of HDL, the "good" form of cholesterol. Both are risk factors for heart disease.

To ensure adequate intake of these nutrients on a vegan diet, it is important to include a variety of plant-based sources in the diet. For example, good sources of iron include lentils, chickpeas, and spinach. Zinc can be found in foods such as cashews, pumpkin seeds, and tofu. B12 can be obtained from fortified plant-based milk and nutritional yeast. Omega-3 fatty acids are present in walnuts, flaxseeds, and chia seeds.

Additionally, supplements can be taken to ensure adequate intake of these nutrients. It is always recommended to consult a healthcare professional or a registered dietitian to ensure that nutritional requirements are being met, especially when following a restricted diet like veganism.

Plant-based diets can help prevent and treat hypertension

Hypertension, or high blood pressure, is a global epidemic and a risk factor for many adverse outcomes, including cardiovascular disease, kidney disease, and death. Lifestyle plays a significant role in the development and maintenance of hypertension, and guidelines from several organizations recommend lifestyle modifications as a first-line intervention for hypertensive patients.

Data supporting the use of plant-based diets in the treatment of hypertension goes back almost a century. Clinical trial data, including randomized controlled trials, have established plant-based diets as an effective lifestyle intervention for high blood pressure.

Observational Evidence

Some of the earliest evidence documenting the lack of hypertension in older adults eating primarily plant-based foods comes from aboriginal societies in Kenya, Western China, the Solomon Islands, and Australia. In modern societies, studies have found that vegetarians and vegans tend to have lower blood pressure than meat-eaters.

Cross-sectional Data

In 1930, it was reported that German monks who ate vegetarian diets had lower blood pressure than those eating meat. Two later studies examining American populations of different religious practices with similar geographic and demographic characteristics provided further insight. The first study compared the blood pressure of vegetarian Seventh-Day Adventists with that of omnivorous Mormons and found lower blood pressure in the Adventists consuming a vegetarian diet. The second study compared vegetarian Adventists to omnivorous Adventists and Mormons and also showed lower rates of hypertension and lower blood pressure among those eating vegetarian diets.

Prospective Cohort Data

Several prospective cohort studies have examined the effects of dietary patterns on blood pressure. The Coronary Artery Risk Development in Young Adults (CARDIA) study followed 4304 young black and white men and women for more than 15 years and found a dose-dependent relationship between plant food intake and a decreasing incidence of elevated blood pressure. In contrast, red and processed meat intake was directly associated with a higher incidence of elevated blood pressure.

Nonrandomized Experimental Evidence

Some of the earliest experimental evidence showing that plant-based diets reduced blood pressure dates back to the 1920s and 1930s. In 1926, a case series of five vegetarian college students found that they had higher blood pressure after including meat in their diet. Ten years later, a study reported an average decline in blood pressure of 60/28 mm Hg in 14 severely hypertensive patients who were treated with a fruit and vegetable diet.

Randomized Experimental Evidence

In the 1980s, Australian researchers performed a pair of randomized controlled trials to test the effects of vegetarian diets on blood pressure. The first study found that consumption of a vegetarian diet lowered blood pressure in normotensive individuals. The second study tested participants on an ovolactovegetarian or omnivorous diet and found that those eating the ovolactovegetarian diet had a mean reduction of 3.5 mm Hg in systolic blood pressure.

The first major randomized controlled trial to evaluate the effects of a mostly plant-based diet on blood pressure was the Dietary Approach to Stop Hypertension (DASH) trial. The DASH diet was created to "have the blood pressure-lowering benefits of a vegetarian diet, yet contain enough animal products to make them palatable to nonvegetarians." The trial had three arms: a control diet representing the "standard" American diet, the DASH diet, and a "fruits and vegetables" diet that was an intermediate between the DASH and control diets. The DASH diet reduced blood pressure by a mean of 5.5/3.0 mm Hg when compared with a control diet.

Mechanisms of Blood Pressure Reduction

Plant-based diets can help facilitate weight loss by being high in fiber, low in fat, and having a reduced energy density. Losing weight and having a lower body weight are associated with lower blood pressure.

A surfeit of total body sodium has long been thought to contribute to hypertension. Vegans consuming a plant-based diet (including fruits, vegetables, legumes, and whole grains) typically consume less sodium than nonvegans. However, it is important to note that a vegan diet can be altered to be high in sodium, especially in the context of processed foods.

Higher potassium intake has also been shown to improve blood pressure. The current animal-heavy Western diet contains less potassium than diets traditionally consumed by humans. Plant-based diets tend to be higher in potassium, which can inhibit sodium reabsorption in the kidneys and lead to cellular hyperpolarization with enhanced net positivity, resulting in decreased cytosolic calcium concentration with resultant vasodilation.

Other Mechanisms

• Redox signaling: Plant-based diets contain polyphenols, which have been shown to act on nitric oxide (NO) signaling and metabolism, augment endothelial nitric oxide synthase expression, and reduce eNOS uncoupling.
• Microbiome: Experimental animal studies indicate an altered microbiome in hypertension, and human data suggest that plant-based diets can positively impact the gut microbiome and blood pressure.
• Epigenetics: Bioactive substances in plant-based foods may modulate blood pressure in an epigenetic fashion, although human data linking plants or plant bioactives to improved blood pressure via epigenetic mechanisms are lacking.
• Increased fiber: Plant-based diets tend to be higher in fiber, which has been associated with lower blood pressure.
• Decreased high-fructose corn syrup: Plant-based diets tend to be lower in high-fructose corn syrup, which has been linked to higher blood pressure.
• Downregulation of the renin-angiotensin and sympathetic nervous systems: Plant-based diets have been shown to downregulate these systems, which play a role in blood pressure regulation.

Plant-Based Diets for Children

Hypertension affects children, and longitudinal studies show that high blood pressure in childhood tracks with high blood pressure as an adult and increases the risk of end-stage renal disease. Plant-based diets have been shown to be beneficial in children. In a small randomized trial, a plant-based diet was found to significantly decrease systolic blood pressure in obese children with hypercholesterolemia.

In summary, plant-based diets have long been used in the management of hypertension, and the preponderance of the evidence suggests that they are a safe and effective way to manage high blood pressure without the side effects of antihypertensive medications.

Vegan diets may increase bleeding and lower blood pressure

A vegan diet may increase bleeding and lower blood pressure. While a vegan diet is associated with many health benefits, such as lower blood pressure and a reduced risk of heart disease, there are some potential drawbacks to be aware of.

Some people who adopt a vegan diet may experience an increase in bleeding. For example, one individual reported that they started "bleeding everywhere" after having an IV removed, which had never happened to them before becoming vegan. Another individual with an anxiety disorder that causes them to pick at the skin around their fingernails noticed that their blood did not coagulate and clot as quickly as it used to after going vegan.

There are a few possible explanations for this. One theory is that a vegan diet can be low in vitamin K, which is important for blood clotting. Additionally, a vegan diet may include higher levels of omega-3 fatty acids, which can act as a blood thinner. However, it is important to note that the impact of a vegan diet on bleeding is not consistent for everyone, and some people may not experience any changes in their blood clotting ability.

Vegan diets are also associated with lower blood pressure, which can be beneficial for heart health. A study comparing the blood pressure of sedentary vegans, endurance athletes consuming a Western diet, and sedentary subjects consuming a Western diet found that blood pressure was significantly lower in the vegan group. This finding suggests that a plant-based diet may be more effective at lowering blood pressure than exercise alone.

In summary, while a vegan diet can offer many health benefits, it is important to be aware of the potential risks as well. Some people may experience increased bleeding due to lower levels of vitamin K or higher levels of omega-3 fatty acids in their diet. Additionally, vegan diets are often associated with lower blood pressure, which can be beneficial for heart health. It is important to consult a healthcare professional before making any significant dietary changes to ensure that you are getting all the necessary nutrients and to monitor for any potential side effects.

A vegan diet can improve cardiovascular health

Veganism is a lifestyle and way of living that seeks to exclude all forms of animal cruelty and exploitation for food, clothing, or any other purpose. In dietary terms, it involves refraining from consuming all products derived wholly or partly from animals.

Lower risk of hypertension

A plant-based diet has been found to be an effective intervention for lowering blood pressure and preventing hypertension. Research has shown that vegans have significantly lower systolic and diastolic blood pressure and a lower prevalence of hypertension compared to meat-eaters, fish-eaters, and vegetarians. This may be due to improved vasodilation, greater antioxidant content, anti-inflammatory effects, improved insulin sensitivity, decreased blood viscosity, and modifications in the renin-angiotensin and sympathetic nervous systems.

Reduced risk of heart disease

A vegan diet can also reduce the risk of heart disease by lowering cholesterol levels. One individual who followed a vegan diet for two months reported a decrease in their total cholesterol to HDL ("good") cholesterol ratio from 6.4 to 3.6 and an increase in their HDL cholesterol level from 0.82 to 1.20, bringing it back to a healthy range.

Improved cardiovascular risk factors

Additionally, it is well-established that meat-eaters have a higher combination of cardiovascular risk factors than vegetarians. However, it is important for vegans to ensure adequate intake of certain nutrients, such as iron, zinc, vitamin B12, and omega-3 fatty acids, as deficiencies in these can increase the risk of heart disease.

Blood-thinning effects

Some individuals have reported experiencing thinner blood after adopting a vegan diet, which can lead to increased bleeding, such as during the removal of an IV. While this may be due to the blood-thinning properties of certain vegan foods or supplements, it is important to consult a healthcare professional for personalized advice.

In conclusion, a vegan diet has the potential to improve cardiovascular health by lowering blood pressure, reducing the risk of heart disease, and improving cardiovascular risk factors. However, it is crucial to ensure adequate nutrient intake to mitigate potential health risks associated with dietary deficiencies.

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