Content Updated March 2014
Last week I was grateful to be asked to speak at a local Yoga Retreat run by my friend and yoga teacher, Alexa Nether. The retreat was held at the beautiful Clarendon Forest Retreat just a 30-minute drive inland from Forster. There was a big focus on relaxation and restoring energy levels and aside from two daily yoga sessions and a nightly yoga nidra, there was delicious vegetarian fare prepared by a local legend.
Health Benefits of a Plant-Based Diet
The Conscious Dietitian and A Plant-Based Diet
I decided to give my talk on the health and environmental benefits of a plant-based diet. I wanted to focus on how a plant-based diet doesn’t mean we have to give up eggs, dairy, meat or fish, but rather can help us be more conscious about our intake of animal foods and make efforts to reduce it.
Aside from discussing how to ensure nutritional adequacy on a plant-based diet we also talked about how small changes can have a big effect on our carbon footprint. An outline of our discussion is outlined below.
Plant-Based Diet and Disease Prevention
Vegetarians have been known to have one of the longest life expectancies, and a balanced plant-based diet can offer many health benefits including protection against;
- Heart disease
- Many types of cancer
- Hypertension (high blood pressure) and stroke
- Overweight and obesity
- Type 2 diabetes
- Diverticular disease
How Does A Plant-Based Diet Promote Disease Prevention
The health benefits of a plant-based may not only be due to the absence of meat but also due to the increased consumption of plant foods. A plant-based diet is generally lower in saturated fat, higher in dietary fibre, low in cholesterol, contains more fruit, vegetables, nuts, legumes and is higher in antioxidants and phytochemicals.
What Are Phytochemicals?
Phytochemicals Protect Plants From Disease
Phytochemicals are chemical compounds produced by plants including fruits and vegetables, which help them thrive or fight off predators, or pathogens.
Plants Are Rich In Phytochemicals
Phytochemicals are not essential to human survival but provide us with numerous health benefits including reducing the risk of chronic disease and helping us to fight existing disease. There may be as many as 100, 000 different kinds of phytochemicals, and often a hundred or more in a single plant. For more information see my post What Are Antioxidants Good For – Protection From Free Radicals and Oxidative Stress.
Are Organic Foods Higher In Phytochemicals?
Plants produce phytochemicals for their own survival and protection. Plants that do not rely on herbicides and pesticides will naturally grow to be stronger as they need to develop their own defences. This leads to the assumption that organic foods are richer in phytochemicals when compared to non-organic food.
Do Vegetarians Have A Higher Intake of Phytochemicals?
Vegetarians often have a higher intake of beans and legumes which are great sources of polyphenols and saponins, as well as whole grains which are high in phenols. This high intake of phytochemicals may attribute to why vegetarians enjoy a lower risk of certain diseases.
What Other Foods Are High In Phytochemicals?
Dark green vegetables such as collards, kale, and spinach, cruciferous vegetables such as broccoli, brussels sprouts, and cabbage, purple/blue fruits such as blueberries and blackberries, as well as tomatoes, citrus fruits, garlic, flaxseeds, and soybeans are some of the superstars of phytochemical-rich foods and are often rich in vegetarian or plant-based diets.
Nutrition On A Plant-Based Diet
How Much Protein Do I Need On A Plant-Based Diet?
Protein is important for growth and repair. A well-balanced plant-based diet with adequate calories will contain a sufficient amount of protein. Good protein sources include legumes, nuts, quinoa, nuts and nut butters, seeds, whole-grains, and tofu. Vegetarians might also enjoy eggs and dairy as good protein sources.
Getting Enough Iron On A Plant-Based Diet
Iron transports oxygen around the body and is important for growth and repair. Plant-based sources of iron include legumes, nuts, seeds, whole grains and green leafy vegetables; they contain non-haem iron which is absorbed much less by the body compared to haem iron from animals.
To enhance the absorption of plant-based non-haem iron;
- Add a source of vitamin C to a meal such as citrus, red peppers or kiwis
- Be mindful of iron inhibitors – phytates in legumes (see my post How To Cook Lentils + 5 Reasons Why We Should Eat Lentils) and unprocessed bran, tannins in tea and coffee, calcium in dairy, and calcium supplements can interfere with absorption.
Getting Enough Vitamin B12 On A Plant-Based Diet
Vitamin B12 is important for the formation of red blood cells and the maintenance of the nervous system. Animal products are the only reliable source of vitamin B-12, so if you are excluding eggs and dairy from your diet, the best sources may be vitamin B-12 fortified milk alternatives or other fortified foods
Tempeh, miso and sea vegetables do not have reliable sources of vitamin B12. These foods often contain an inactive form of vitamin B-12 which may interfere with the absorption of active vitamin B-12.
Getting Enough Omega-3 Fatty Acids On A Plant-Based Diet
Omega-3 Fatty Acids including DHA and EPA provide numerous health benefits and are associated with the omega-3 fatty acids found in seafood. Vegetarian sources of omega-3’s only contain ALA which can be converted to EPA and DHA but at a low conversion rate (~10%) and there are numerous inhibitory factors.
Vegetarian sources of ALA omega-3 fatty acid include flaxseed seeds (and flaxseed oil), chia seeds, walnuts, canola oil, soy products. To increase the conversion of ALA to DHA and EPA;
- Limit intake of omega-6 fatty acids such as sunflower, safflower, corn, soybean oil, as well as trans-fatty acids, and alcohol,
- Supplement with DHA microalgae supplements if you are pregnant or lactating,
- See my post How To Get Your Omega-3s For Vegetarians and Vegans.
Getting Enough Calcium On A Plant-Based Diet
It is a common misconception that calcium comes only from cows. The recommendations are set at 3 to 4 servings of dairy products per day to meet the Recommended Dietary Intake (RDI) for calcium. There are other sources of calcium including Asian greens such as guy choy and choy sum, kale and to a lesser extent broccoli and bok choy. Calcium-fortified milk alternatives are also available, and tofu is often pressed with calcium-salts. To ensure adequate calcium absorption;
- Minimize your intake of calcium inhibitors with your calcium-rich foods which include foods high in iron or phytates (such as bran and un-soaked legumes),
- Ensure adequate vitamin D which may mean supplementing in the winter (see my post Vitamin D Foods For Vegetarians),
- Limit salt and caffeine intake as they can increase calcium excretion.
Getting Enough Vitamin D On A Plant-Based Diet
Vitamin D is important for bone health and our main source is from the sun, but we can get some through our diet. The only vegetarian sources are eggs (minimal) and fortified foods such as fortified milk alternatives. Vitamin D deficiency risk increases with age due to reduced skin thickness. See my post Vitamin D Foods For Vegetarians for more information.
Getting Enough Zinc On A Plant-Based Diet
The availability of zinc in plant foods tends to be lower than in animal foods. Zinc is important for numerous functions including growth and development, reproduction, night vision, appetite, taste sensation, immune function healthy skin and wound healing. Plant-based foods that are high in zinc include legumes, whole grains, soy, nuts, seeds, eggs and cheese. To increase absorption of zinc;
- Soak legumes before cooking to removed phytates,
- Sprout grains, nuts and seeds (How To Make Sprouts and Health Benefits of Sprouts)
- See my post How To Get Enough Zinc for Vegans and Vegetarians.
The Environmental Impacts of Eating Meat
Livestock and Fed Production
The production of meat has the environmental costs of both meat and plant food production. Most animals are fed on grains and legumes- approximately 40% of the world’s grain harvest is currently fed to animals (including genetically modified corn and soy).
Animal Production and Greenhouse Gas Emissions
Food production is the second highest contributor to Australia’s greenhouse gas emissions. Approximately 70% of these emissions come from animal production.
Livestock and Damage To The Environment
In Australia, hard-hoofed animals are responsible for erosion, damage to waterways, damage to ecosystems, deforestation, depletion of non-renewable aquifers (underground water), contamination of streams and lakes, and pollution through pesticide dipping, hormone and antibiotic treatments and other medications.
Livestock and Water Usage
A 500g steak needs 4,660 litres of water, mainly through the production of feed and pasture irrigation. In Australia, the water used for the pastures of grazing animals is more than the water used in the production of vegetables, fruit, sugar and rice combined.
The Sustainability of Eating A Plant-Based Diet
Plant-Based Protein Versus Animal Protein
On average plant protein production requires 10 times less land that the production of meat protein.
Plant Proteins Use Fewer Fertilizers Compared to Animal Protein
Plant production uses much fewer phosphate fertilizers that meat production. The world’s supply of phosphate fertilizers is depleting and the price are increasing. Phosphate emissions can pollute non-agriculture soil and waterways.
Plant-Based Proteins and Water Usage
Production of plant food uses 2-5 times less water than animal foods. Animal foods are highly water-intensive due to the need to grow feed for the animal to eat.
Plant-Based Proteins Use Fewer Fossil Fuels
Depending on the type of farming, plant food production can use 6-20 times fewer fossil fuels than animal food production.
Steps to a Healthier You and Healthier Environment
A worldwide campaign to reduce chronic disease risk associated with over-consumption of meat. See my previous blog post here for more information.
If you eat fish, ask about how it was caught and the sustainability of the species. If you love red meat, think about more sustainably species such as kangaroo. Form your own opinion on if you want Genetically Modified foods in your household.
Everyone needs to set goals, but we rarely sit down and write them down. If you want to adopt a more plant-based diet, aim small and write your goals down. Try starting with one new legume recipe a week and pretty soon you will have a great repertoire of healthy legume recipes that are not only healthy and delicious but also cost-effective.
References for Health and Environmental Benefits of a Plant-Based Diet
Website: Alexa Nether- Yogic
Website: Dietitians Association of Australia
Website: Meatless Monday
Website: Livable Future Blog
Book: Ethical Eating – Angela Crocombe
Book: The Choice Guide to Food – Rosemary Stanton
Book: The Conscious Cook – Giselle Wilkinson
Rachel Dickens, The Conscious Dietitian, is a Registered Dietitian and Certified Diabetes Educator. She graduated with her Masters in Nutrition and Dietetics in 2010 from Griffith University. She strives to provide evidence-based nutrition information with a focus on plant-based nutrition and share some of her favourite seasonal recipes and sustainable eating tips.