Plant-Based Diets: Superior To Meat-Based Ones?

A plant-based diet is often chosen for ethical, environmental, or health reasons. Research has shown that a vegetarian or vegan diet can be beneficial to health, with lower rates of heart disease, type 2 diabetes, and some cancers compared to diets high in meat and animal products. However, there are also some potential health risks associated with plant-based diets, including a higher risk of stroke and lower intakes of certain nutrients such as protein, vitamin B12, vitamin D, calcium, and iodine. Overall, a well-chosen vegan diet can provide adequate nutrition, and long-term health is generally similar to that of comparable meat-eaters.

Plant-based diets are linked to lower rates of heart disease

Plant-based diets are associated with lower rates of heart disease. Research has shown that a plant-based diet can prevent, manage, and even reverse heart disease. Plant-based diets are beneficial for heart health because they contain no dietary cholesterol, very little saturated fat, and an abundance of fibre.

The DASH (Dietary Approaches to Stop Hypertension) diet is a plant-based diet that has been associated with a decreased risk of heart failure. The DASH diet is rich in fruits, vegetables, whole grains, and nuts, with the addition of some fish, poultry, and low-fat dairy products, while minimising red meat, sugar, and processed foods. The Mediterranean diet is another plant-based diet that has been linked to a reduced risk of heart failure. This diet emphasises the consumption of vegetables, fruits, whole grains, and nuts, with a moderate intake of extra virgin olive oil and fish.

Multiple studies have found that a plant-based diet can lead to improvements in cardiovascular mortality and lower rates of ischaemic heart disease. Plant-based diets can also help improve risk factors for heart disease, such as high blood pressure, high cholesterol, inflammation, and excess weight.

However, it is important to note that the quality of the plant-based diet is essential. Consuming whole, unprocessed plant foods is associated with a lower risk of cardiovascular disease compared to consuming unhealthy plant-based foods, such as fried foods and processed foods.

Vegetarians and vegans have lower body mass index, serum low-density lipoprotein and blood pressure

Vegetarian and vegan diets are associated with lower body mass index (BMI), serum low-density lipoprotein (LDL) cholesterol, and blood pressure compared to diets that include meat. These differences in health markers are thought to be due to the lower intake of saturated fats and higher intake of dietary fibre in plant-based diets.

Body Mass Index

Vegetarians and vegans typically have a lower BMI than meat-eaters. For example, in the EPIC-Oxford study, the mean BMI of both male and female vegetarians and vegans was approximately 1-2 kg/m^2 lower than that of meat-eaters. This difference in BMI could be due to differences in protein, polyunsaturated fat, and fibre intake between the dietary groups.

Serum Low-Density Lipoprotein

Vegetarians and vegans also tend to have lower serum LDL cholesterol levels. In the EPIC-Oxford study, vegan men had 0.85 mmol/l lower LDL cholesterol than meat-eaters, while vegan women had 0.49 mmol/l lower LDL cholesterol. This difference may be due to the lower body mass index, replacement of saturated fats with polyunsaturated fats, and higher fibre intake in plant-based diets.

Blood Pressure

Plant-based diets are also associated with lower blood pressure. In the EPIC-Oxford study, vegans had significantly lower blood pressure than meat-eaters, and this difference was partly due to their lower BMI. Other factors that may contribute to lower blood pressure in vegetarians and vegans include higher consumption of potassium, lower consumption of sodium, and improvement of glucose tolerance.

Plant-based diets may increase the risk of stroke

A plant-based diet is often considered healthier than a meat-based diet. Research has linked plant-based diets to lower rates of heart disease, type 2 diabetes, and some cancers. However, a new study published in the medical journal *The BMJ* suggests that plant-based diets may have a previously unrecognized health risk: an increased risk of stroke.

The Study

The study, led by Tammy Tong, PhD, analysed the risk of stroke and other health problems over two decades among nearly 50,000 people based on their diets. The types of stroke were also analysed, including bleeding into the brain (haemorrhagic stroke) and non-bleeding stroke (ischemic stroke).

The Results

The results showed that compared to meat eaters:

• Pescatarians had 13% lower rates of heart disease.
• Vegetarians had 22% lower rates of heart disease.
• Vegetarians had a 20% higher risk of stroke, with the overall risk being three extra cases per 1,000 people over 10 years.
• The higher stroke risk among vegetarians was mostly due to haemorrhagic stroke.
• The higher stroke risk was not observed among pescatarians.

Limitations and Further Research

It's important to note that this study has some limitations. It was observational, meaning it simply observed the outcomes among different diet groups over time without accounting for all relevant factors. Additionally, the data regarding diet was self-reported, which may not always be reliable. Furthermore, the study was not large enough to reliably differentiate between the risks of stroke in vegans and vegetarians.

While the findings suggest a possible link between plant-based diets and an increased risk of stroke, more research is needed to confirm and understand this association fully. Future studies should aim to determine how a vegetarian diet may increase the risk of stroke and whether this risk is outweighed by the cardiac and other health benefits of plant-based diets.

Takeaway Messages

The data supporting a whole food plant-based diet for stroke prevention and treatment is not as strong as for ischaemic heart disease, partly due to less extensive research on this topic. However, some observations can be made. Firstly, those who eat more fruits and vegetables and less meat have a lower incidence of ischaemic stroke. Secondly, diet patterns that emphasize whole plant foods and minimize animal-derived foods, such as the DASH and Mediterranean diets, have been associated with a lower risk of stroke.

While the EPIC-Oxford and Adventist Health Studies did not consistently find an association between vegetarian or vegan diets and stroke risk, a 2019 update from EPIC-Oxford reported an increased risk of haemorrhagic stroke in vegetarians. However, this study also showed a reduced risk of ischaemic heart disease and ischaemic stroke in the vegetarian group. A meta-analysis and systematic review of prospective cohort studies from 2019 did not show any impact of a vegetarian diet on stroke risk when compared to non-vegetarian diets.

In contrast, a more recent study from a Taiwanese cohort found a significant reduction in ischaemic and haemorrhagic stroke in vegetarians, with approximately a 60% reduced risk of both types of strokes. This discrepancy may be due to differences in the cohorts, as the Taiwanese cohort did not include smokers or drinkers, and they consumed more soy foods.

A 2021 study examining the impact of a healthy versus unhealthy plant-based diet found that those most adherent to a healthy plant-based diet had a 10% reduced risk of developing a stroke. Additionally, an umbrella review of meta-analyses found that fruit and vegetable consumption reduced the risk of stroke, while red and processed meat increased the risk.

In conclusion, while there may be an increased risk of stroke associated with plant-based diets, particularly haemorrhagic stroke, the benefits to heart health and the reduced risk of ischaemic stroke far outweigh this potential risk. More data is needed to confirm the impact of vegetarian and vegan diets on stroke risk, but it is essential to stick to a healthy plant-based diet for overall health and minimize the consumption of processed, unhealthy plant-based foods.

Plant-based diets may be linked to a lower risk of certain cancers

Research has shown that a plant-based diet may be linked to a lower risk of certain cancers. A plant-based diet is one that is predominantly made up of fruits, vegetables, legumes, and little to no meat or other animal products. Vegans, who consume no animal products, have been found to have the lowest rates of cancer, followed by vegetarians, who avoid meat but may consume animal products such as milk or eggs.

Plant-based diets are rich in phytochemicals, which are chemical compounds that protect the body from damage and interrupt processes in the body that encourage cancer production. Plant-based diets are also high in fiber, which has been linked to a reduced risk of breast and colorectal cancer.

Phytochemicals are beneficial to the body in several ways. They contain antioxidants, which protect the body from damage caused by radiation, viruses, and exposure to other chemicals. They also decrease inflammation and interrupt processes in the body that encourage cancer production.

Two of the most beneficial phytochemicals are antioxidants and carotenoids. Antioxidants protect and restore cells in the body, while carotenoids are fat-soluble compounds that are linked to a reduced risk of heart disease, cancer, macular degeneration, and cataracts.

The combination of certain plant-based foods has also been found to be more effective at slowing tumor growth than individual foods alone. For example, a combination of tomatoes and broccoli was found to be more effective at slowing prostate cancer tumor growth than either food alone.

Plant-based diets are also high in natural fiber, which has been linked to a reduced risk of cancer and moderate insulin levels. Young women who consumed the most fiber-rich diets were found to be 25% less likely to develop breast cancer later in life. Additionally, each 10 grams of daily fiber was associated with a 10% lower risk of colorectal cancer.

Healthy bacteria in the digestive tract can also ferment fiber and starches, producing compounds that promote normal colon development and reduce inflammation. These bacteria also convert some phytochemicals into more active forms.

In summary, a plant-based diet may be linked to a lower risk of certain cancers due to the high content of phytochemicals and fiber. The combination of certain plant-based foods may also be more effective at cancer prevention than individual foods alone.

Plant-based diets may be linked to a higher risk of bone fractures

There is a growing trend of people adopting plant-based diets due to concerns for animal welfare, the environment, and health. While plant-based diets offer many health benefits, recent studies suggest that they may also be linked to an increased risk of bone fractures. This review aims to explore this potential link and provide detailed information on the topic.

Plant-Based Diets and Bone Health

Several studies have found an association between plant-based diets and bone health. A study published in the *British Medical Journal* (BMJ) found that vegetarians had a 20% higher risk of stroke, mainly due to a higher risk of hemorrhagic stroke. Another study, the EPIC-Oxford study, which included 65,000 participants, found that vegetarians had a higher risk of bone fractures, particularly hip fractures, compared to meat-eaters. Similarly, a cross-sectional study using data from the US National Health and Nutrition Examination Survey (NHANES) found that higher adherence to plant-based diets was associated with an increased risk of osteopenia and osteoporosis.

Potential Reasons for the Link

There are several potential reasons for the link between plant-based diets and bone fractures. One reason could be the lower intake of calcium and protein in vegans, which can lead to low bone mineral density. Additionally, vegetarians and vegans typically have a lower body mass index (BMI), which can be a protective factor against fall-related fractures. However, a higher BMI can also increase the risk of certain types of fractures, such as wrist and hip fractures.

Mitigating the Risk

It is important to note that the risk of bone fractures in those following plant-based diets can be mitigated by ensuring adequate intake of certain nutrients. Calcium is an important mineral for bone health, and it can be obtained from plant-based sources such as leafy greens, almonds, and fortified plant-based milk. Vitamin D also plays a crucial role in bone health, and it can be obtained through sun exposure or supplementation. Additionally, including protein-rich plant foods such as pulses, soy products, and nuts can help maintain bone health.

While plant-based diets offer many health benefits, there may be a link between these diets and an increased risk of bone fractures. However, this risk can be mitigated by ensuring adequate intake of calcium, vitamin D, and protein. More research is needed to fully understand the relationship between plant-based diets and bone health.

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