Plant-based, vegetarian and vegan diets

There’s no debating the science. A diet packed with plant foods does wonders for your health. But what exactly is a plant-based diet and how does it compare to a vegan or vegetarian diet? Should we be ditching meat and dairy?

Fruit and vegetables laid out on a table with blueberries in a heart shape
‘Eat food, not too much, mostly plants’ – Michael Pollen

What is a plant-based diet?

A plant-based diet is a way of eating where the focus is on filling up your plate with plant foods.

Some examples of plant foods include:

  • Vegetables
  • Fruit
  • Legumes (like lentils and chickpeas)
  • Whole grains
  • Nuts
  • Seeds.

The closer these foods resemble how they’re found in nature (i.e. the less processing) and the more of them on your plate – the better for your body.

This way of eating isn’t about being restrictive. People who eat a mainly plant-based diet may still choose to eat small amounts of meat, poultry, fish, seafood and dairy (also known as semi-vegetarian, flexitarian or pescatarian). The beauty is that there is no ‘one-size fits all’ approach.

What’s the difference between a vegan and vegetarian diet?

Some people eating a plant-based diet may choose not to eat meat and animal products for various reasons. A vegan diet excludes all meat and animal products (meat, poultry, fish, seafood, dairy and eggs), whereas a vegetarian diet excludes meat, poultry, fish and seafood. However, there are a few variations of a vegetarian diet that depend on whether you eat or exclude eggs, dairy and fish (see table below).

Different styles of plant-based eating

Name of diet Description
Semi-vegetarian or flexitarian 

includes eggs and dairy

may include small amounts of meat, poultry, fish and seafood

Pescatarian

includes eggs, dairy, fish and seafood

excludes meat and poultry

Ovo-vegetarian

includes eggs

excludes meat, poultry, fish, seafood and dairy
Lacto-vegetarian

includes dairy

excludes meat, poultry, fish, seafood and eggs

Vegetarian

(a.k.a. lacto-ovo vegetarian)

includes eggs and dairy

excludes meat, poultry, fish and seafood

Vegan

excludes all meat, poultry, fish, seafood, eggs and dairy 

What are the benefits of a plant-based diet?

A diet centred on plenty of whole, minimally processed plant foods lowers your risk of heart disease and benefits your overall health1.

Vegetables, fruit, legumes, whole grains, nuts and seeds are low in saturated fat, contain heart-healthy fats and are an excellent source of fibre. They give our bodies vitamins, minerals, antioxidants and phytochemicals, which offer protection against disease2.

Our research on dietary patterns clearly shows that vegan and vegetarian diets are associated with a lower risk of heart disease3. People that follow a vegan or vegetarian diet generally have lower blood pressure and Low Density Lipoprotein (LDL) cholesterol than non-vegetarians3. Some studies have shown that well-planned vegan and vegetarian diets help people to control their blood sugar levels and may reduce inflammation in the body too2,4.

The key thing to note when looking at the evidence is that vegans and vegetarians tend to lead a healthier life overall, which explains some, but not all, of the lower risk seen in these groups. For example, people who follow a vegetarian diet may be more physically active and drink less alcohol.

Should I switch to a vegan diet?

To eat more plant foods, you don’t necessarily need to adopt a vegan or vegetarian diet. For many of us, just making an effort to eat less processed foods and more plant foods every day will do wonders for your health and risk of heart disease.

A high intake of vegetables and fruit (regardless of whether meat or dairy are eaten) is associated with a lower risk of heart disease and early death5-6.

Around the world, we see various ways of eating which include varying amounts of meat and dairy that support a long and healthy life. Well-known examples from the ‘Blue Zones’ include the traditional Mediterranean diet, the vegetarian diet of the Seventh-Day Adventists, and the largely plant-based diet of the Okinawans in Japan. One thing that all of these populations have in common is that their diet is primarily plant-based.

How can I eat more plant-based foods?

A good place to start is to think about an approach that is realistic for you and your family. Consider taking small steps towards getting more plant foods on your plate.

Here are some vegetable and legume recipe ideas to get you started.

Is a plant-based diet healthy?

A plant-based diet isn’t automatically healthy. Hot chips, biscuits and soft drinks can all be vegan/vegetarian foods. Too much saturated fat, sugar and salt from any source isn’t good for your health. An increasing number of processed plant foods are making their way onto supermarket shelves from vegetarian hotdogs to vegan sweet treats. Some of these foods may actually contain more salt and sugar than regular products.

Remember any foods that have been highly processed should be eaten mindfully – whether they are plant-based or not. Learn how to read food labels to help you to choose products that are right for you.

Nutrients for vegan and vegetarian diets

If you do choose to eat a vegan or vegetarian diet, be mindful that it can take careful planning to get all of the essential nutrients you need especially for pregnant/breastfeeding women, infants and young children. Alternative sources of protein (like tofu, tempeh, legumes, nuts and seeds), omega-3 fats, iron, zinc and calcium may be needed. You also need to consider vitamin B12 if you are excluding all animal products. Fortified foods or supplements may be needed (particularly for B12).

If you’re thinking about switching to a vegetarian or vegan diet then talk to your GP or practise nurse and get help from a dietitian or registered nutritionist.

What does the Heart Foundation recommend?

There are plenty of ways to eat for a healthy heart and a range of diets can be heart healthy – those with small amounts of meat, poultry, fish, seafood, eggs and dairy, and those without.

Whatever diet you choose, we recommend loading up your plate with plant foods like vegetables, fruit, whole grains, legumes, nuts and seeds and making them the hero of your meals and snacks.

What’s most important is the quality of your overall diet and getting the fundamentals of eating a healthy diet right. Most of us would benefit from eating more plant foods and less processed foods without having to avoid animal products altogether. A ‘flexitarian’ approach may be the most realistic and sustainable way for many of us to adopt a plant-based diet.

Get healthy eating tipsShould I switch to a plant-based diet?
Lily Henderson, NZRD

Lily Henderson, NZRD

National Nutrition Advisor

I am passionate about improving the health of all Kiwis from young through to old. I have enjoyed working in nutrition in the UK, Australia and New Zealand.

[1] Dinu M, Abbate R, Gensini GF et al. Vegetarian, vegan diets and multiple health outcomes: a systematic review with meta-analysis of observational studies. Critical Reviews in Food Science Nutrition. 2017;57(17):3640-3649.

[2] Melina V. Craig W, Levin S. Position of the Academy of Nutrition and Dietetics: Vegetarian Diets. Journal of the Academy of Nutrition and Dietetics. 2016;116(12):1970-1980

[3] Heart Foundation. Dietary Patterns and the Heart. Background paper. 2013.

[4] Eichelmann F, Schwingshackl L, Fedirko V et al. Effect of plant‐based diets on obesity‐related inflammatory profiles: a systematic review and meta‐analysis of intervention trials. Obesity Reviews. 2016;7(11):1067-1079.

[5] Wang X, Ouyang Y, Liu J et al. Fruit and vegetable consumption and mortality from all causes, cardiovascular disease, and cancer: systematic review and dose-response meta-analysis of prospective cohort studies. British Medical Journal. 2014;349:g4490.

[6] Aune D, Giovannucci E, Boffetta P et al. Fruit and vegetable intake and the risk of cardiovascular disease, total cancer and all-cause mortality - a systematic review and dose-response meta-analysis of prospective studies. International Journal of Epidemiology. 2017;46(3):1029-1056.