Plant-Based Diets: Who's On Board?

A plant-based diet is recommended by many physicians, dieticians, and health organisations. The Academy of Nutrition and Dietetics, the American Dietetic Association, the British National Health Service, and the British Dietetic Association all endorse plant-based diets. The World Health Organization has also stated that eating 50 grams of processed meat per day can increase the risk of colorectal cancer by up to 18%.

Plant-based diets are associated with a reduced risk of heart disease, type 2 diabetes, obesity, and other health conditions. They are also thought to be less expensive than omnivorous diets. Research shows that these diets are cost-effective, low-risk interventions that may lower body mass index, blood pressure, and cholesterol levels.

Lower risk of heart disease

A plant-based diet is recommended by many physicians and health organisations as a way to lower the risk of heart disease. Research has shown that a plant-based diet can not only prevent heart disease but also help manage and even reverse it.

The American Heart Association published two studies in the Journal of the American Heart Association, which found that eating a plant-based diet at any age may lower the risk for heart attacks and other types of cardiovascular disease. One study found that eating a plant-centred diet in young adulthood lowered the risk in middle age for heart attack, stroke, heart failure and several other cardiovascular conditions. The second study found that eating plant-based foods that lower cholesterol levels reduced the risk of heart disease in postmenopausal women.

The World Health Organization states that cardiovascular disease is the leading cause of death in the United States and around the world. Eating habits and other lifestyle factors play a key role in determining the risk of heart disease. A plant-based diet, combined with regular exercise and a healthy overall lifestyle, can prevent, delay, and even reverse heart disease and other cardiovascular events.

Plant-based diets benefit heart health because they contain no dietary cholesterol, very little saturated fat, and abundant fibre. Meat, cheese, and eggs, on the other hand, are packed with cholesterol and saturated fat, which cause plaque buildup in the arteries, eventually leading to heart disease.

The American Heart Association recommends that people can choose among plant foods that are as close to natural as possible, not highly processed. They suggest that individuals can include animal products in moderation from time to time, such as non-fried poultry, non-fried fish, eggs and low-fat dairy.

The Mediterranean diet, which has a foundation of plant-based foods, has been shown to reduce the risk of heart disease, metabolic syndrome, diabetes, certain cancers, depression, and, in older adults, the risk of frailty, along with better mental and physical function. Vegetarian diets have also been shown to support health, including a lower risk of developing coronary heart disease, high blood pressure, and diabetes.

A plant-based diet can also help improve several risk factors for heart disease, including high blood pressure, high cholesterol, inflammation, and excess weight.

Lower risk of type 2 diabetes

A plant-based diet is associated with a reduced risk of developing type 2 diabetes and is highly effective in its treatment. Plant-based diets improve glycemic control, body weight, plasma lipid concentrations, and blood pressure, while reducing the risk of cardiovascular and microvascular complications.

Benefits of a plant-based diet in preventing and treating type 2 diabetes

• Improved glycemic control: Plant-based diets, particularly vegan diets, improve glycemic control in individuals with type 2 diabetes. A meta-analysis of six randomised controlled trials (involving 255 participants) demonstrated that vegetarian diets were associated with a 0.4% greater reduction in glycated haemoglobin (HbA1c) when compared with other prescribed eating patterns for diabetes.
• Improved body weight: Weight management plays an important role in improving insulin sensitivity and glycemic control and reducing cardiovascular disease (CVD) risk factors. Individuals following vegetarian, especially vegan, diets have lower mean BMIs than non-vegetarians. Population studies have revealed that body weight increases progressively with increased meat consumption.
• Reduced risk of cardiovascular and microvascular complications: The effects of plant-based diets on glycemia, body weight, plasma lipids, and blood pressure collectively reduce the risk of CVD, the leading cause of morbidity and mortality in diabetes patients. Plant-based diets are also associated with reduced CVD risk and may help reverse atherosclerotic plaques.

Mechanisms by which plant-based diets improve insulin resistance and weight management

• Improved insulin sensitivity: Insulin resistance and subsequent impairment in β-cell function are the hallmarks of type 2 diabetes pathophysiology. Plant-based diets are beneficial for patients with diabetes by improving insulin sensitivity and improving body weight. High-fat diets downregulate the genes required for mitochondrial oxidative phosphorylation in skeletal muscle and appear to disrupt the normal intestinal barrier to bacterial endotoxins, which may disrupt glucose oxidation processes.
• Improved weight management: Weight management plays an important role in improving insulin sensitivity and glycemic control and reducing CVD risk factors. Excess body weight is associated with the risk of CVD and all-cause mortality among people with type 2 diabetes. Plant-based diets may prevent weight gain and are an effective weight management tool.

Plant-based diets and diabetes-related complications

• Cardiovascular disease and risk factors: Plant-based diets have been shown to improve glycemic control while also reducing key diabetes-related macrovascular and microvascular risks. Plant-based diets are associated with reduced CVD risk and may help reverse atherosclerotic plaques.
• Chronic kidney disease: Plant-based diets are associated with a lower risk of chronic kidney disease. A Western dietary pattern, characterised by a high consumption of red meat, fat, salt, and sugar, is a major contributor to metabolic disturbances leading to the progression of kidney disease.
• Diabetic neuropathy: Diabetic neuropathy is a microvascular complication of diabetes that can be debilitating. At least two small studies have shown that a plant-based diet can ameliorate diabetic neuropathic pain.

Lower risk of obesity

Plant-based diets are associated with a lower risk of obesity. Plant-based diets are typically lower in calorie density and fat content, which are beneficial for weight loss. Plant-based diets are also associated with improved gut microbiota, increased insulin sensitivity, and reduced trimethylamine-N-oxide (TMAO), which can help to reduce body weight.

Plant-based diets have been shown to be effective in the treatment of obesity. Plant-based diets can help to reduce body weight, improve cardiovascular health, lower blood pressure, and improve glucose metabolism.

Several studies have found that individuals consuming plant-based diets tend to have lower body mass indexes (BMIs) than those consuming non-plant-based diets. In addition, plant-based diets have been found to be beneficial in the treatment, prevention, and reversal of other illnesses, such as type 2 diabetes and hypertension.

Plant-based diets are a healthy and sustainable way to improve overall health, especially for those who are obese or overweight.

Lower risk of cancer

Research has shown that a plant-based diet may be one of the most powerful tools in cancer prevention. A plant-based diet is typically full of fruits, vegetables, legumes, whole grains, nuts, seeds, oils, and beans. It is associated with a significantly lower risk of cancer due to its high-fibre content and high levels of antioxidants and anti-inflammatory compounds.

Phytochemicals

Plant-based diets are full of phytochemicals, which are chemical compounds that protect the body from damage and interrupt processes in the body that encourage cancer production. Phytochemicals also decrease inflammation. Two of the most helpful phytochemicals are:

• Antioxidants: This type of phytochemical protects the body from damage. Antioxidants neutralise damage processes while protecting and restoring cells. Some foods that contain high levels of antioxidants include dark chocolate, apples with the peel, avocados, artichokes, red cabbage, tea, coffee, nuts, and grains.
• Carotenoids: These are fat-soluble compounds that are naturally present in many fruits, grains, oils, and vegetables such as carrots, sweet potatoes, squash, spinach, apricots, green peppers, and leafy greens. They are highly pigmented, so look for natural foods that are red, orange, yellow, and green. Carotenoids have been linked to reducing the risk of heart disease, cancer, macular degeneration, and cataracts.

Fibre

Plant-based diets are high in natural fibre, which has been shown to reduce cancer risk and moderate insulin levels. Young women who ate the most fibre-rich diets were 25% less likely to get breast cancer later in life. Other research finds that each 10 grams of daily fibre could lower the risk of colorectal cancer by 10%. Fibre also helps promote normal colon development and reduce inflammation.

Vitamins and Minerals

Vitamins and minerals found in plant-based foods have been shown to reduce the risk of several types of cancer. For example, eating 6 ounces of whole-grain foods each day may decrease your colorectal cancer risk by 21%.

Other Compounds

Other healthful compounds with potential anti-cancer activity include lignans and saponins, resistant starch, and antioxidants from flavonoids, inositol, sterols, and other phytochemicals.

Research

A large study in the International Journal of Cancer found that those who ate the most plant foods and the least animal foods reduced their risk of cancer by 15%. Another large Harvard study followed men and women for 34 years and found that just following a healthy diet reduced the risk of dying from cancer by 30%. Adhering to all five healthy lifestyle factors (never smoking, maintaining a healthy weight, regularly exercising, consuming alcohol only in moderation, and eating a healthy diet) reduced the risk of dying from cancer by 65%.

Lower risk of Alzheimer's disease

A plant-based diet is associated with a lower risk of Alzheimer's disease. Research shows that saturated and trans fats found in dairy products, meats, pastries, and fried foods can increase the risk of cognitive decline. In the Adventist Health Study comparing meat eaters and vegetarians, it was found that dementia is more common among meat eaters.

Populations that have higher intakes of plant-based foods have a reduced risk for Alzheimer's disease. In a study that tracked the intake of fruits and vegetables of women for 11 years, it was found that women who ate the most green leafy and cruciferous vegetables had less decline in brain function compared with women who ate these vegetables less frequently. These foods are high in both folate and antioxidants, two important nutrients for healthy brain function.

The Journal of Alzheimer's Disease has published a detailed study on the role of diets in modifying the risk of Alzheimer's disease. The findings show that regimes that include more vegetables, legumes, whole grains, and fruits reduce the chance of developing this terrible neurodegenerative disorder. According to the paper, more plant-based diets, like the Mediterranean and traditional diets in China, Japan, and India, have been demonstrated to reduce the risk of developing Alzheimer's disease, contrary to the Western diet.

The Mediterranean diet has been shown in both large population studies and randomized clinical trials to reduce the risk of heart disease, metabolic syndrome, diabetes, certain cancers, depression, and in older adults, a decreased risk of frailty, along with better mental and physical function. Vegetarian diets have also been shown to support health, including a lower risk of developing coronary heart disease, high blood pressure, and diabetes.

Plant-based diets offer all the necessary protein, fats, carbohydrates, vitamins, and minerals for optimal health, and are often higher in fiber and phytonutrients. However, some vegans may need to add a supplement (specifically vitamin B12) to ensure they receive all the nutrients required.

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