Exploring Varied Plant-Based Diets: A Comprehensive Guide

There are many different types of plant-based diets, and they are categorized based on the extent to which animal products are included. The most common types of plant-based diets are: semi-vegetarian or flexitarian, pescatarian, lacto-ovo vegetarian, vegan, and whole-food, plant-based. A semi-vegetarian or flexitarian diet is primarily vegetarian but includes a small amount of meat, poultry, fish, and seafood, as well as eggs and dairy. A pescatarian diet is also primarily vegetarian but includes shellfish and fish. A lacto-ovo vegetarian diet includes eggs and dairy products but excludes meat, fish, and poultry. A vegan diet is entirely plant-based, excluding all animal-derived products and ingredients, such as meat, fish, dairy, and eggs. A whole-food, plant-based diet, like a vegan diet, excludes all animal-derived products and ingredients, and focuses on whole and minimally refined plant-based foods.

Vegetarian diets

The first is the lacto-ovo vegetarian diet, which includes dairy products and eggs, but no meat, poultry, fish, or seafood. The next is the lacto-vegetarian diet, which includes dairy but excludes eggs and any animal products with them.

There are also semi-vegetarian or flexitarian diets, which are primarily vegetarian but include small amounts of meat, poultry, fish, and seafood, and may include dairy and eggs.

Vegetarians need to be mindful of getting enough nutrients, especially protein, iron, calcium, zinc, and vitamin B12, which are found in smaller amounts in vegetarian sources or are less easily absorbed by the body than those in meat or fish. For example, vegetarians can get protein from pulses (beans, peas, and lentils), eggs, and meat alternatives like tofu, nuts, and seeds. They should eat a variety of different protein sources to get the right mix of amino acids, which are used to build and repair the body's cells.

Iron and vitamin B12 are two nutrients that vegetarians can struggle to get enough of. Good vegetarian sources of iron include pulses, dried fruit, dark green vegetables, wholemeal bread and flour, and fortified cereals. Vitamin B12 is only found naturally in animal products, so vegetarians should eat eggs and dairy or include fortified foods like yeast extracts, breakfast cereals, and soya products in their diet.

Vegan diets

There are several types of vegan diets, each with its own specific focus and restrictions. Here are some of the most common types:

• Raw vegan diet: Raw vegans eat only raw plant foods, including uncooked fruits and vegetables, nuts, seeds, sprouted and soaked grains, cold-pressed oils, and fermented foods. This diet is based on the theory that cooking reduces the nutritional value of food. While it may provide more vitamins, minerals, fibre, and antioxidants, it can also lead to deficiencies in protein, vitamins D and B12, calcium, iron, and iodine.
• Vegan keto diet: This is a very low-carb, high-fat, and moderate-protein diet. On this diet, 75%-80% of calories come from fat, 10%-20% from protein, and 5%-10% from carbs. It involves eating high-fat vegan foods and restricting grains, starchy vegetables, beans, legumes, and high-sugar fruits. Like the raw vegan diet, it is very restrictive and may lead to nutrient deficiencies.
• Vegan diabetic diet: Diabetic diets are moderately low in carbohydrates, especially refined carbs that quickly raise blood sugar. A vegan diabetic diet focuses on whole grains, beans, legumes, and healthy fats to help control blood sugar and keep it stable.
• High-protein vegan diet: Protein is often lacking in a vegan diet, so this diet focuses on higher-protein plant foods, such as legumes, soy, and peas. It is popular among vegan athletes and bodybuilders who need more protein for muscle growth and repair.
• Alkaline vegan diet: This diet prioritises foods based on their pH value, with high-pH (alkaline) foods taking precedence. It is believed that eating less acidic foods can aid weight loss, increase energy, and prevent chronic illnesses, although these benefits are not proven. This diet restricts some major protein sources for vegans, such as lentils, tofu, and tempeh, so there is a risk of not getting enough protein.
• Vegan anti-inflammatory diet: Research shows that eating fewer animal products can reduce inflammation linked to diseases like type 2 diabetes, heart disease, and cancer. This diet focuses on fresh, whole foods and limits sugars and highly processed foods.
• Mediterranean vegan diet: This diet is similar to the Mediterranean diet, which is known to have health benefits, but without the fish, dairy, and eggs. It is rich in fruits, vegetables, grains, beans, nuts, seeds, and unsaturated oils.
• Low-carb vegan diet: This diet focuses on plant foods that are low in carbs, such as non-starchy vegetables, high-fat fruits, low-sugar fruits, and oils.

A well-planned vegan diet can provide all the nutrients needed to maintain a healthy body. However, it is important to be mindful of potential deficiencies, such as protein, calcium, omega-3 fatty acids, zinc, vitamin B12, and vitamin D.

In addition to health benefits, vegan diets are environmentally friendly. Research shows that producing a gram of protein from beef requires nearly 100 times as much land as producing the same amount from plant-based sources.

When transitioning to a vegan diet, it is recommended to focus on the foods you can enjoy and gradually replace animal products with plant-based alternatives. It is also important to ensure you are getting enough nutrients, either through a varied diet or by taking supplements.

Flexitarian diets

The flexitarian diet is a semi-vegetarian style of eating that encourages eating less meat and more plant-based foods. It is a flexible approach to vegetarianism, where one can eat animal products in moderation. This diet was popularised by dietitian Dawn Jackson Blatner, who created it to help people reap the benefits of vegetarian eating while still enjoying meat, fish, and dairy in moderation.

The flexitarian diet has no clear-cut rules or recommended numbers of calories and macronutrients. Instead, it is based on the following principles:

• Eat mostly fruits, vegetables, legumes, and whole grains.
• Focus on protein from plants instead of animals.
• Be flexible and incorporate meat and animal products from time to time.
• Eat the least processed, most natural forms of foods.
• Limit added sugar and sweets.

The flexitarian diet may aid weight loss and reduce the risk of heart disease, cancer, and type 2 diabetes. It may also be good for the environment, as it can help preserve natural resources by decreasing greenhouse gas emissions, land use, and water consumption.

However, planning flexitarian food choices carefully is important to prevent nutritional deficiencies. Possible nutrient deficiencies to be aware of include vitamin B12, iron, zinc, and calcium.

Some common reasons for adopting a flexitarian diet include religious restrictions, weight management, health consciousness, animal welfare, and environmental concerns.

Mediterranean diets

The Mediterranean diet is a plant-based dietary pattern inspired by the traditional eating habits of the countries bordering the Mediterranean Sea, such as Greece, Spain, and Italy. It is rich in vegetables, fruits, whole grains, legumes, nuts, and seeds, with moderate amounts of fish and poultry, and minimal amounts of red meat and processed foods.

The Mediterranean diet is highly nutritious and provides all the necessary protein, fats, carbohydrates, vitamins, and minerals for optimal health. It is particularly high in fiber and phytonutrients.

Health Benefits

The Mediterranean diet has been linked to numerous health benefits, including:

• Reduced risk of heart disease, metabolic syndrome, diabetes, certain cancers (specifically colon, breast, and prostate cancer), depression, and frailty in older adults.
• Improved mental and physical function in older adults.
• Improved cognitive function and better gut health.
• Longevity.

Environmental Benefits

In addition to the health benefits, adopting a Mediterranean diet can also positively impact the environment. By reducing the consumption of animal-based products, this dietary pattern can help:

• Lower greenhouse gas emissions.
• Conserve water and land resources.

Sample Meals

• Greek Briam – Baked Summer Vegetables: a vegetable and olive oil-based dish.
• Pasta with zucchini, sun-dried tomatoes, ricotta, and pine nuts.
• Bean burgers with garlic and sage.
• Lentil soup with olive oil and orange.
• Greek omelette with zucchini and mint.
• Avocado toast with caramelized balsamic onions.
• Chickpea and quinoa grain bowl.
• Tomato and artichoke gnocchi.
• Zucchini-chickpea veggie burgers with tahini ranch sauce.

Whole-food, plant-based diets

Principles of a Whole-Food, Plant-Based Diet:

• Whole Foods: Emphasises natural, unprocessed, or minimally processed foods.
• Plant-Based: Prioritises food from plants, limiting or excluding animal products like meat, milk, eggs, and honey.
• Flexibility: While similar to vegan diets, it allows for some animal products and is more focused on including whole foods rather than excluding specific items.

Food Groups:

• Fruits: All types of fruits, including apples, bananas, grapes, strawberries, citrus fruits, etc.
• Vegetables: A variety of veggies like peppers, spinach, kale, peas, carrots, broccoli, etc.
• Tubers: Starchy root vegetables such as potatoes, sweet potatoes, yams, and cassava.
• Whole Grains: Grains, cereals, and starches in whole form (e.g. quinoa, brown rice, oats, whole wheat).
• Legumes: All kinds of beans, lentils, and pulses.
• Nuts, Seeds, and Healthy Fats: Avocados, olive oil, nuts, nut butters, seeds (e.g. almonds, cashews, pumpkin seeds).
• Plant-Based Proteins: Tofu, tempeh, and plant-based protein sources or powders without added sugar or artificial ingredients.

Benefits of a Whole-Food, Plant-Based Diet:

• Weight Management: These diets tend to be lower in calories and higher in fibre, making it easier to lose weight and maintain a healthy weight.
• Disease Prevention and Management: Can help prevent, halt, or even reverse chronic diseases like heart disease, type 2 diabetes, arthritis, and improve liver and kidney function.
• Improved Health Outcomes: May lead to better skin, more energy, improved sports performance, and enhanced reproductive health.
• Environmental Benefits: Reduces environmental footprint, lowers resource use, and contributes to sustainability.
• Cost Savings: Whole and minimally processed plant-based foods tend to be more affordable, potentially reducing grocery bills.

Tips for Adopting a Whole-Food, Plant-Based Diet:

• Focus on including a variety of whole plant-based foods in your meals.
• Minimise or limit animal products, using them as a complement to your plant-based dishes.
• Choose quality animal products if you include them in your diet.
• Avoid highly processed foods, including processed vegan-friendly options like plant-based meats and cheeses.
• Base your meals on large servings of whole grains, starchy vegetables, and legumes.
• Include plenty of vegetables, especially cruciferous and leafy green varieties.
• Enjoy fresh fruit without restriction.
• Learn to cook without vegetable oils and margarines, even olive oil.
• Practice moderation with nuts and seeds due to their high-fat content.
• Drink plenty of water.

Frequently asked questions