It’s no secret that eating fresh fruits and vegetables will benefit our health, however it is common for most of us to forget about our fruits and vegetables and consume large amounts of animal products such as meat. In fact, less than 4% of Australian adults and 0.5% of Australian kids are meeting the recommended serves of fruits, vegetables and legumes. Despite this, plant-based diets are one of the biggest food and health trends this year with more than 2 million Australians currently reporting their diet to be ‘almost all’ or ‘all’ vegetarian. Many people are now also self-proclaimed ‘flexitarians’ who incorporate vegan or vegetarian products into their overall diet instead of a complete diet overhaul. So what exactly is a plant-based diet and is there any benefit in switching to one?
What is a plant-based diet?
Plant-based diets don’t necessarily mean following a strict vegetarian or vegan diet and avoiding all foods that come from animals such as meat, eggs and cheese.
A vegan diet excludes all animal products, like meat, seafood, poultry, eggs and dairy products. A vegetarian diet generally excludes animal foods like meat and poultry, whereas foods like eggs, milk products and/or seafood may still be included.
A whole foods, plant-based diet is simply a diet rich in foods that come from plants such as fruits, vegetables, legumes, wholegrain breads and cereals and nuts and seed. Plant-based diets can still contain smaller amounts of lean meats, eggs, seafood and dairy products.
What are the benefits of following a plant-based diet?
1. Plant-based diets reduce your risk of chronic lifestyle diseases
The most important benefit of following a plant-based diet is that they help protect against many of the chronic lifestyle diseases and health concerns that we face today.
A 2017 study which followed two groups of people with various chronic health conditions got half of the study participants to follow a plant-based diet, and the other half to follow their regular diet. After just 6 months, researchers found that those following the plant-based diet decreased their total cholesterol, dropped their medication use by 29%, reduced their HbA1c (a marker of type 2 diabetes), reduced their BMI and lost an average of 12.1kg of weight. These improvements continued when researchers did a follow up 12 months after the study finished. The participants who followed their normal diet had no significant reductions in BMI or weight, their total cholesterol reduced only marginally and their medication use increased by 8%.
This is only one of the many studies that show the benefits of following a plant-based diet, emphasising how it is an effective option for improving various conditions such as type two diabetes, heart disease, high blood pressure, high cholesterol and cancer.
In 2015, the International Agency for Research on Cancer looked at more than 800 studies researching the link between red meat, processed meat and cancer. They declared red meat as “probably carcinogenic” (has the potential to cause cancer) and linked it to colorectal, pancreatic and prostate cancer. Processed meat (e.g. ham, sausages) was declared as “carcinogenic to humans”, based on evidence that eating processed meats causes colorectal cancer. The researchers stated that although red meat has some nutritional benefits, it is best to limit intake to promote good health.
2. Plant-based diets are associated with lower levels of anxiety and depression
Mental disorders, especially depression, account for the highest burden of global disability, meaning years of quality life lost. Almost 1 in 2 Australians will experience a mental health condition in their lifetime. There is a strong link between the quality of people’s diets and their risk of mental disorders. Better quality diets are consistently associated with a reduced risk for depression. Unhealthy dietary patterns high in processed foods, red meat, processed meat, added sugars, sugar-sweetened beverages, trans fat and sodium and low in fruits, vegetables, wholegrains, nuts, seeds, fibre, omega-3 fatty acids and polyunsaturated fatty acids are associated with an increased risk for depression and often also anxiety. Many people argue that this link exists because many people with poor mental health turn to poor quality comfort foods such as chocolate and takeaway food but research shows that these foods cause depression in the first place.
Neurotransmitters or brain chemicals are produced in our brain from the nutrients that come directly from the foods we eat. The quality of your diet can either impair or enhance the production of neurotransmitters. Variety in the diet is key as diets with a higher variety of fruits and vegetables have been shown to be more effective for improving mood. Eating more plant-based foods can have a positive effect on mood and mental health by calming down inflammation, clearing up oxidative stress and improving our gut microbiota which play a role in mood regulation and stress hormones. In fact a 2017 study called the SMILES trial showed that a modified Mediterranean diet- a plant-based diet that contains smaller amounts of meat and dairy- could improve or even reverse depression in a small sample of people.
3. Plant-based diets are better for our gut health
Plant-based diets are richer in fibre, the edible parts of plants which our body is unable to digest resulting in partial or complete fermentation in the large intestine by our gut bacteria. Fibre improves our health because when our gut bacteria ferment or break down fibre they produce compounds called short-chain fatty acids (SCFAs) which have multiple health benefits. SCFA’s help fuel and nourish other healthy gut bacteria, strengthen the bowel lining protecting it against harmful bacteria and reduce inflammation in the body.
People with healthier guts have lower rates of heart disease, bowel cancer and inflammatory bowel disease, better immune systems, lower levels of inflammation in the body, and are more likely to achieve a healthy weight and prevent excessive weight gain.In fact, eating three serves of wholegrain or high-fibre plant-based foods per day reduces a person’s bowel cancer risk by approximately 17%
Typical western diets that are high in red meat, animal protein, salt and added sugar, and low in fruits, vegetables and wholegrains not only cause imbalances in our gut bacteria but also increase our risk of early death, cancer, weight gain and chronic lifestyle diseases such as heart disease and type two diabetes.
4. Plant-based diets contain more nutrients
It is no secret that fruits and vegetables are high in nutrients. Plant-based foods (including wholegrain breads and cereals and legumes) are high in a number of nutrients including a special group of antioxidants called phytochemicals and fibre. These are both some of the most health-promoting and disease-fighting nutrients which can only be found in plant foods. Plants contain thousands of phytochemicals which all have many beneficial roles in the body, including:
- Anti-oxidation: a process which protects the body’s cells from damage
- Lowering cancer activity by preventing tumour growth, detoxifying cancer causing substances and preventing the growth of bad cells
- Improved immunity
- Protecting against some diseases like osteoporosis, some cancers, cardiovascular disease, macular degeneration and cataracts
- Improving cholesterol levels
5. Plant-based diets are less expensive
Not only do plant-based diets give you the many health benefits we have discussed above, they can also be easier on the pocket. A 2015 study found that an every-day meat-containing diet cost an extra $14.40 USD per week (equivalent to $18.50 AUD per week).When you think about how much you currently spend weekly on meat and other animal-based products, it really does add up. Using the average calculation of an extra $18.50 per week for meat products, this adds up to an additional $962 a year spent on meat products. Better yet, buying fruit and vegetables that are seasonal and locally grown can save you lots of money too.
Take home message
Increasing our intake of plant-based foods and reducing our intake of meat and animal products can truly benefit our health, food budget and the environment. Plant-based diets don’t need to be followed strictly or involve cutting out all animal products in order to be beneficial. Simply striving for a diet that contains plenty of fruit and vegetables, legumes, wholegrains, nuts and seed is what count. Our favourite way to do this is by making the vegetables or salad the hero of your dish or simply incorporating one or two meat-free meals per week. If you are considering transitioning to a strict vegetarian or vegan diet, or simply want some easy ideas of how to incorporate more plant-based foods, book in a consult with one of our dietitians who can ensure you are consuming all of the essential nutrients and are not missing out on any key nutrients such as protein, iron, zinc, B12 and folate.
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