Frequently Asked Questions

This page answers the most frequent questions we hear from both healthcare professionals and the wider community about plant-based nutrition and health.

The largest professional body representing dieticians and nutritionists in the world (the Academy of Nutrition and Dietetics), state clearly that well designed plant based diets are nutritionally complete, and puts one at reduced risk of most chronic lifestyle related conditions including, coronary heart disease, T2DM, certain types of cancer and obesity. They also reiterate it can be eaten at every stage in life.

The abstract states: “Vegetarians and vegans are at reduced risk of IHD, T2DM, hypertension, certain types of cancer, and obesity. Low intake of saturated fat and high intake of rich fibre and phytochemicals… lower total and LDL cholesterol and better serum glucose control.” [1]

However, nutritional needs vary from one life stage to another. Read more about nutrition across life stages.

View key references.

The topic of diet can be addressed in relation to a condition, concern or as part of preventative healthcare.

A simple structure to follow during a consultation to open a conversation about diet is:

  1. Raise how the concern or condition could relate to diet: “There is a link with (insert condition) and (diet or salt etc) intake, I need to explore that further.”
  2. Gently, but directly, ask/invite: “Often our eating habits are playing a larger role in our health than we realise. Can you share a snapshot of what you have eaten in the last 24 hours?”
  3. Non-judgemental: Dietary intake is often the sum of many habits, some of which a patient may have struggled with or have no idea about the consequences. ‘Now’ is always a good time to start improving at a rate they can manage

The RACGP SNAP Guidelines provide useful guidance to assist general practitioners (GPs) and practice staff to work with patients on lifestyle risk factors, including nutrition.

Learn more about speaking to patients about diet by watching a presentation from Advisory Council member Dr Alyce Churchill. Or download our free ‘Plant-based nutrition and health guide‘ and accompanying tools to include nutritional approaches to disease prevention and care.

In 2017–18, 2 in 3 (67%) Australians aged 18 and over were overweight or obese, up 10% from 1995. [1]

Although genetic factors contribute to obesity, the increased prevalence of this condition during the last century (particularly in the last 3 decades) confirms that environmental factors play a major role.[2] The Western diet, which provides highly palatable, energy-dense foods rich in fat and sugar, is conducive to weight gain.[3] These foods activate reward systems in the brain, up-regulate the expression of hunger signals, and blunt the response to satiety signals, promoting overconsumption.[4]

Randomized trials show that low-fat vegan diets promote greater weight loss than typical low-fat diets, and improve plasma lipids, insulin sensitivity, and other measures.[5],[6] A study of a near-vegan diet in heart patients, used in combination with exercise and stress management, showed sustained weight loss over a 5-year period.[7]

The effect of a low-fat vegan diet on body weight is mainly attributable to its low energy density. That is, because the diet is very low in fat (which is energy-dense) and high in fiber (which has essentially no calories), energy intake falls without a person needing to intentionally cut calories or even to be aware of the change. A secondary contributor to weight loss is the tendency of a low-fat vegan diet to increase postprandial energy expenditure. In the after-meal period, as foods are digested and their nutrients are absorbed, energy expenditure rises—an effect called the thermic effect of food. This effect can be larger or smaller depending on the foods consumed during a specific meal and also depending on the habitual diet. Transitioning to a low-fat vegan diet causes the thermic effect of food to increase by roughly 15%.[8]

Low-fat vegan diets are much more effective for weight control, compared with Mediterranean diets. In a randomized cross-over trial including overweight participants, a low-fat vegan diet led to a weight loss of 6.0 kg over 16 weeks, compared with no net weight loss on a Mediterranean diet.[9]

Time to introduce your patients to WFPB nutrition? Share our ‘General public‘ portal, filled with plenty of easy-to-understand  resources, tools and recipes.

View key references.

The only supplement that is always required for people following a plant-exclusive diet is vitamin B12. Vitamin B12 is necessary for normal red blood cell formation, tissue and cell repair, nerve health, and DNA synthesis. A B12 deficiency can lead to permanent nervous system problems.

Because Vitamin B12 is made by a microorganism found in soil and water which is then consumed by animals, it is effectively only found in food of animal origin. However, owing to modern farming practices, even the animals are routinely supplemented. The upshot is that B12 supplementation is essential for anyone following a plant-based diet. Supplementation of 50-500 micrograms of cyanocobalamin per day is best practice. This is preferable to relying on fortified foods, which may not meet daily needs without careful planning to ensure correct doses at regular intervals during the day.

Approximately 10-30% of older adults in Australia are commonly affected by atrophic gastritis, which can interfere with absorption of vitamin B12 [1]. Consequently, regardless of diet adults over age 50 should consider receiving the majority of their vitamin B12 from a supplement.

As with any eating pattern, nutrient status should be considered on a case by case basis, with testing, supplementation and/or incorporation of fortified foods considered if required. For example, when it is hard to get enough sunlight for adequate vitamin D production a supplement is advisable, and this is always important to consider for people with darker skin tones on any diet.

Learn more about other nutrients of note.

View key references.

Nearly 1 in 2 (46%) Australians aged 16–85 had experienced a mental disorder during their lifetime. [1]

A diet pattern rich in whole plant foods is associated with better mental health, whereas western-style diet, characterized by a high consumption of red and/or processed meat, refined grains, sweets, high-fat dairy products, butter, potatoes and high-fat gravy, and low intakes of fruits and vegetables, may increase the risk of depression. [2]

Studies have shown that diets rich in neuro-protective vitamins and minerals such as B vitamins, Omega 3 DHA, iron, magnesium, and zinc are beneficial to our brain and mental health. [3]

Hydration also has a significant impact on mental health. Regularly and adequately hydrating with water and other healthful options, such as herbal tea, can improve focus, increase performance, reduce fatigue, and best support psychological wellbeing.

Listen to this podcast from Physicians Committee for Responsible Medicine to learn more about the connection between food and mood.

View key references.

Almost 1 in 5 Australians live with at least 1 chronic condition, such as heart disease, stroke, dementia, cancer, or diabetes.[1] It is well documented that people with chronic conditions can also be more vulnerable to the effects of certain communicable diseases, including Influenza and COVID-19.

A dietary pattern characterised by healthy plant-based foods has been associated with lower risk and severity of COVID-19.[2] Multiple studies continue to support the benefits of a plant-based diet, a healthy gut microbiome and adequate vitamin D.

Further explore some of the recent studies emphasising these findings at Plant-Based Health Professionals UK, lead by our International Advisor Dr Shireen Kassam.

View key references.

Is a plant-based diet suitable for all life stages?
[1] Melina V, Craig W, Levin S. Position of the Academy of Nutrition and Dietetics: Vegetarian Diets. J Acad Nutr Diet. 2016;116(12):1970-1980. doi:10.1016/j.jand.2016.09.025

What diet is best for weight control?
[1] Overweight and obesity. Australian Institute of Health and Welfare. https://www.aihw.gov.au/reports/australias-health/overweight-and-obesity
[2] Tremblay A, Pérusse L, Bouchard C. Energy balance and body-weight stability: impact of gene-environment interactions. Br J Nutr. 2004;92 Suppl 1:S63-6. doi: 10.1079/bjn20041144
[3] Lindberg MA, Dementieva Y, Cavender J. Why Has the BMI gone up so drastically in the last 35 years? J Addict Med. 2011;5(4):272-8. doi: 10.1097/ADM.0b013e3182118d41
[4] de Macedo IC, de Freitas JS, da Silva Torres IL. The Influence of Palatable Diets in Reward System Activation: A Mini Review. Adv Pharmacol Sci. 2016;2016:7238679. doi: 10.1155/2016/7238679
[5] Barnard ND, Scialli AR, Turner-McGrievy G, et al. The effects of a low-fat, plant-based dietary intervention on body weight, metabolism, and insulin sensitivity. Am J Med. 2005;118(9):991-7. [PMID:16164885]
[6] Huang RY, Huang CC, Hu FB, et al. Vegetarian Diets and Weight Reduction: a Meta-Analysis of Randomized Controlled Trials. J Gen Intern Med. 2016;31(1):109-16. doi: 10.1016/j.amjmed.2005.03.039
[7] Ornish D, Scherwitz LW, Billings JH, et al. Intensive lifestyle changes for reversal of coronary heart disease. JAMA. 1998;280(23):2001-7. doi: 10.1001/jama.280.23.2001
[8] Kahleova H, Petersen KF, Shulman GI, et al. Effect of a Low-Fat Vegan Diet on Body Weight, Insulin Sensitivity, Postprandial Metabolism, and Intramyocellular and Hepatocellular Lipid Levels in Overweight Adults: A Randomized Clinical Trial. JAMA Netw Open. 2020;3(11):e2025454. doi: 10.1001/jamanetworkopen.2020.25454
[9] Barnard ND, Alwarith J, Rembert E, et al. A Mediterranean Diet and Low-Fat Vegan Diet to Improve Body Weight and Cardiometabolic Risk Factors: A Randomized, Cross-over Trial. J Am Coll Nutr. 2021. doi: 10.1080/07315724.2020.1869625

Does WFPB nutrition mean supplements become necessary?
[1] Vitamin B12. National Health and medical Research Council. https://www.nrv.gov.au/nutrients/vitamin-b12

Can nutrition impact mental health?
[1] Mental Health. Australian Institute of Health and Welfare. https://www.aihw.gov.au/reports/mental-health-services/mental-health
[2] Li Y, Lv MR, Wei YJ, et al. Dietary patterns and depression risk: A meta-analysis. Psychiatry Res. 2017;253:373-382. doi: 10.1016/j.psychres.2017.04.020
[3] Gómez-Pinilla F. Brain foods: the effects of nutrients on brain function. Nat Rev Neurosci. 2008;9(7):568-578. doi:10.1038/nrn2421

Can a WFBD reduce the impact of COVID-19?
[1] Australia’s Health 2022 in Brief. Australian Institute of Health and Welfare. https://www.aihw.gov.au/reports/australias-health/australias-health-2022-in-brief/summary
[2] Kim H, Rebholz CM, Hegde S, et al. Plant-based diets, pescatarian diets and COVID-19 severity: a population-based case–control study in six countries. 

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