Plant-Based Diets: Healthy Choice Or Health Risk?

A plant-based diet is often regarded as the healthiest approach to eating, with benefits extending beyond weight loss. It can be defined as a general approach to eating, where one consumes more plant-based foods and fewer animal-based ones. Plant-based diets are associated with a reduced risk of heart disease, type 2 diabetes, certain cancers, and improved weight management. They are also environmentally friendly, reducing greenhouse gas emissions, water consumption, and land use. However, some argue that plant-based diets may not be suitable for everyone, as they can be challenging to ensure adequate protein, vitamin, and mineral intake.

Plant-based diets are associated with a reduced risk of heart disease

Plant-based diets are recommended for coronary heart disease prevention. However, not all plant foods are necessarily beneficial for health. Plant-based diets that emphasise healthy plant foods such as whole grains, fruits, vegetables, nuts, legumes, oils, tea and coffee are associated with a lower risk of coronary heart disease. On the other hand, plant-based diets that emphasise less healthy plant foods such as refined grains, sugar-sweetened beverages, juices, sweets and desserts are associated with a higher risk of coronary heart disease.

The Adventist Health Study 2 (AHS-2) found that vegetarians had a lower risk of all-cause mortality and increased life expectancy when compared to non-vegetarians. The European Prospective Investigation into Cancer and Nutrition-Oxford (EPIC-Oxford) study found that vegetarians were less likely to develop ischemic heart disease or have a stroke when compared to meat eaters. The ARIC (Atherosclerosis Risk in Communities) study found that diets higher in plant foods and lower in animal foods were associated with a lower risk of cardiovascular morbidity and mortality in a general population.

Plant-based diets are associated with a lower risk of heart disease due to their higher content of dietary fibre, antioxidants, unsaturated fat and micronutrients, and lower content of saturated fat and heme iron. Plant-based diets can also help to improve glycemic control and insulin regulation, enhance lipid profile, reduce blood pressure, improve vascular health and decrease inflammation.

However, it is important to note that not all studies have found a link between plant-based diets and a reduced risk of heart disease. The EPIC-Oxford study did not find a difference in all-cause mortality between vegetarians and non-vegetarians. Additionally, the EVADE CAD trial found no difference in lipid profiles between a vegan diet and the American Heart Association-recommended diet.

They can help prevent and manage type 2 diabetes

Plant-based diets are associated with a reduced risk of developing type 2 diabetes and are highly effective in its treatment. Diets that emphasise whole grains, vegetables, fruits, and legumes and exclude animal products improve blood glucose concentrations, body weight, plasma lipid concentrations, and blood pressure, and play an important role in reducing the risk of cardiovascular and microvascular complications.

Improving blood glucose control

A plant-based diet can help improve blood glucose control. A meta-analysis of six randomised controlled trials found that vegetarian diets were associated with a 0.4% greater reduction in glycated haemoglobin (HbA1c) when compared with other prescribed eating patterns for diabetes.

Improving insulin sensitivity

Plant-based diets, particularly vegan diets, can improve insulin sensitivity. A randomised trial assigned 75 participants who were overweight or obese to a low-fat plant-based diet or no diet changes for 16 weeks. Meal-stimulated insulin secretion markedly increased in the intervention group compared with controls. This study demonstrates the potential that a plant-based eating pattern can play a role in reversing beta-cell dysfunction and peripheral insulin resistance in patients with type 2 diabetes.

Improving weight management

Weight management plays an important role in improving insulin sensitivity and glycemic control and reducing cardiovascular disease (CVD) risk factors. Plant-based diets, especially vegan diets, have been associated with lower mean BMIs compared with non-vegetarians. Population studies have revealed that body weight increases progressively with increased meat consumption.

Reducing cardiovascular disease risk factors

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. A meta-analysis of nine randomised controlled trials in patients with type 2 diabetes, comparing vegetarian interventions with control diets, showed significant improvements in CVD risk factors, including lipids, blood pressure, glycemic control, body weight, and abdominal adiposity.

Reducing microvascular complications

Diabetic nephropathy is a microvascular complication of diabetes that can be debilitating. A 20-week randomised, controlled trial using a low-fat, vegan intervention demonstrated improved nerve function, as measured by electrochemical skin conductance in the foot, and reduced pain, compared with an untreated control group.

Plant-based diets focus on foods primarily from plants, including fruits, vegetables, nuts, seeds, oils, whole grains, legumes, and beans. It doesn't mean that you are vegetarian or vegan and never eat meat or dairy. Rather, you are proportionately choosing more of your foods from plant sources.

Plant-based diets can lead to weight loss

Plant-based diets are a powerful way to achieve good health and can lead to weight loss. Plant-based diets are mainly characterised by the elimination of all types of meat, including fish, and occasionally other animal products like eggs and dairy. Plant-based diets are full of fibre, rich in vitamins and minerals, free of cholesterol, and low in calories and saturated fat. Plant-based diets have been proven to prevent and reverse heart disease, improve cholesterol, and lower blood pressure. Plant-based diets also lead to weight loss, even without exercise or calorie counting. Replacing high-fat foods with fruits, vegetables, whole grains, and legumes naturally reduces calorie intake.

Plant-based diets can benefit both your health and your waistline. Studies show that plant-based diets have exploded in popularity, especially among dieters interested in cutting back on their consumption of animal products. Plant-based diets have a positive impact on the planet and reduce the risk of chronic disease. Plant-based diets may also lower cholesterol and blood pressure levels and reduce the risk of certain conditions like diabetes.

Weight loss is possible on a plant-based diet, but your results may vary depending on several factors, including which foods you eat, your activity level, and your health status. Research has turned up some promising results. One study found that following a whole-food, plant-based diet for three months led to an average weight loss of around 19 pounds, even without limiting portion sizes. After an entire year, participants lost a whopping 25 pounds on average while following a plant-based diet. Another study found that following a healthy plant-based diet for six weeks resulted in nearly 10 pounds of weight loss on average.

Types of plant-based diets

The term "plant-based diet" refers to any eating pattern that puts plant foods (like fruits and veggies) front and centre. Vegan and vegetarian diets are specific plant-based diets, and there are less restrictive approaches as well, like the flexitarian diet. How often you include animal products on a plant-based diet is up to you. Some plant-based diets allow you to enjoy animal products like meat, cheese, and eggs in moderation. There are no hard-and-fast rules — it just depends on what works best for you.

Pros and cons of plant-based diets

Plant-based diets can help you lose weight. They emphasise foods that are high in fibre yet low in calories, and they also limit many foods that are less nutritious. You’re kicking processed foods pretty much out of your diet, which tend to have empty calories. It’s worth noting that some foods marketed as being vegan or vegetarian are still highly processed. Those should also be limited or avoided.

Plant-based diets can also promote heart health. Eating a plant-based diet is a big deal in relation to heart health, and research confirms this. Plenty of research supports that it not only lowers your chances of developing heart disease, but also helps keep your blood pressure, blood sugar, and cholesterol levels in check. Plus, some individuals are able to take fewer medications as their medical conditions tend to improve.

Plant-based diets are also good for your gut. Because the plant-based diet encourages so many fibre-rich foods, it’s easy to fit enough fibre into your daily diet. This is good for supporting your gut health, which is linked to so many things like digestive regularity and fostering a diverse microbiota.

Plant-based diets may also give you longevity. You may live longer if you eat a plant-based diet. This is backed by a study that found that following a healthy plant-based diet was linked to a lower risk of death among adults in the United States.

However, there are also some cons to plant-based diets. Preparing healthy, plant-based meals at home can be time-consuming. Plant-based diets often require more cooking and meal prep, plus more frequent trips to the grocery store. Since the foods are fresher, they are also more perishable. Using frozen fruits and vegetables and canned beans will reduce the time you need to shop and cook.

There are also fewer options at restaurants. Eating out may be tricky or a touch boring, depending on the options you have around. The good news is that many restaurants now have plant-based options, and some restaurants do focus on plant-based meals.

Making the switch can be tough. Depending on your current diet, transitioning to a plant-based diet might be a bit challenging at first. You have to ditch the meat-at-every-meal mentality, which for some can be really hard or just really different. The key would be to find some delicious plant-based recipes to try, such as plant-based breakfasts.

Plant-based diets can also be confusing. Because there’s no clear-cut definition of what a plant-based diet should look like, you can follow it in many different ways. Some eat meat, some eat dairy, some are vegan, and some are vegetarian. The flexibility can be a pro or a con, really. When doing your own research, take note of the definition of plant-based so you can understand how to mimic the benefits you're reading about. To make it less confusing, start slowly. For example, you might want to try having meatless Mondays. From there, you can decide what type of plant-based eating plan could work for you.

They may reduce the risk of certain cancers

Plant-based diets are recommended due to their association with a reduced risk of certain cancers. Research has shown that eating a plant-based diet can lower the chances of developing specific types of cancer.

Plant-based diets are rich in nutrients, including vitamins, minerals, phytochemicals, and fibre, all of which contribute to cancer prevention. Phytochemicals are chemical compounds found in plant-based foods that protect the body from damage and interrupt processes that encourage cancer production. For example, antioxidants, a type of phytochemical, neutralise cell damage caused by radiation, viruses, and exposure to harmful chemicals, thus reducing the risk of cancerous cell division.

One specific cancer that has been linked to plant-based diets is colorectal cancer. Eating whole grains and legumes can significantly reduce the risk of developing this type of cancer. Research suggests that consuming 6 ounces of whole grains daily may decrease colorectal cancer risk by 21%. Additionally, young women who incorporate high-fibre diets are 25% less likely to develop breast cancer later in life.

Another way in which plant-based diets may reduce the risk of certain cancers is by helping to regulate insulin levels. Plant-based diets are often high in fibre, which has been shown to moderate insulin levels and lower the risk of cancer. This is particularly relevant for type 2 diabetes, as plant-based diets have been shown to prevent, manage, and even reverse this condition by improving insulin function and increasing the body's ability to regulate blood sugar.

Furthermore, plant-based diets are typically lower in saturated fat and trans fat, which are found in meat, dairy, and fried foods. These fats have been linked to an increased risk of Alzheimer's disease and other cognitive conditions. By avoiding these foods, plant-based diets may offer a protective effect against these conditions and potentially reduce the risk of associated cancers.

Plant-based diets are environmentally friendly

A plant-based diet is a powerful way to achieve good health. It consists of exclusively plant foods, including fruits, vegetables, grains, and legumes, and avoids meat, dairy, and eggs. Plant-based diets are environmentally friendly and may be associated with several health benefits.

Adopting a plant-based diet not only benefits your health but can also help protect the environment. People who follow plant-based diets may have smaller environmental footprints. Sustainable eating habits can help reduce greenhouse gas emissions, water consumption, and land use for factory farming, all of which are factors in global warming and environmental degradation.

A review of 63 studies showed that the largest environmental benefits were observed from diets containing the least amount of animal-based foods, such as vegan, vegetarian, and pescatarian diets. The study reported that a shift from Western diet patterns to more sustainable, plant-based dietary patterns could achieve a 70% reduction in greenhouse gas emissions and land use and a 50% reduction in water use.

Plant-based diets offer all the necessary protein, fats, carbohydrates, vitamins, and minerals for optimal health and are often higher in fiber and phytonutrients. Research has linked plant-based diets to lower rates of heart disease, type 2 diabetes, obesity, and certain types of cancer. Plant-based diets can also lead to weight loss, even without exercise or calorie counting, as they are lower in calories and saturated fat.

There are several interpretations of plant-based diets, including:

• Vegetarian: Excludes meat, poultry, and fish but may include dairy and eggs.
• Vegan: Excludes all animal products, including meat, dairy, eggs, and honey.
• Pescatarian: Includes eggs, dairy, fish, and seafood but excludes meat and poultry.
• Flexitarian: A flexible approach that cuts down on meat intake and primarily fills the diet with plants, with some animal products included.

Frequently asked questions