Dr Renae Thomas | Contributors - Nourish plant-based living

Dr Renae Thomas

Dr Renae Thomas is a family, preventive and lifestyle medicine physician with a passion for the role of nutrition, physical activity, social connections and stress reduction in disease prevention and reversal. After obtaining her medical degree at Monash University in Australia, Renae relocated to California, where she completed her residency and Public Health masters at Loma Linda University. Renae serves on the International Advisory Council of the Australian health-promotion charity, Doctors For Nutrition.


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Getting started with a wholefoods approach

Wholefoods may just save your life, and at the very least, they will deliver a host of health benefits. Here’s what you need to know to get started.

There are many ways to approach a plant-based diet; but from a medical perspective, the gold standard is wholefood plant-based nutrition, often simply called WFPB. This eating pattern includes an abundance of fruits, vegetables, intact wholegrains, legumes, nuts, seeds, herbs, and spices while excluding all animal products, including red and white meat, seafood, eggs, and dairy products. It eliminates fast foods, fried foods, refined and processed foods (including flour, oil, and refined sugars), and highly processed foods like chips, lollies, and chocolate – even if they are vegan. Salt, caffeine, alcohol, and artificial sweeteners are also avoided. We might think of this way of eating as a nutrition prescription for wellness.

The evidence-backed benefits of WFPB nutrition include:

  • reduced overall mortality (dying from any cause)
  • lower risk for many types of cancer
  • lower chance of developing type 2 diabetes mellitus
  • significantly less cardiovascular disease, such as heart attack or stroke
  • lower blood pressure
  • lower cholesterol
  • healthier body weight.

We might think of this way of eating as a nutrition prescription for wellness.

For those struggling with diet-related chronic disease, switching to a WFPB pattern of eating can often significantly improve or even reverse the disease process. In fact, a report prepared by the EAT-Lancet Commission, consisting of 37 world-leading scientists, suggested shifting to a plant-based diet could save 11 million lives per year. It’s the number one eating pattern with the potential to save lives!

CUT THE CALORIE COUNTING

Calorie counting and weighing or measuring foods is largely unnecessary for health; however, if you are transitioning from a refined, calorie-dense, standard Western diet to a WFPB nutritional pattern, understanding calorie density in order to thrive is important. Typically the majority of foods eaten on a WFPB nutritional plan are lower in calorie density, which simply means that larger portions need to be eaten to make up the same amount of calories. For example, one tablespoon of oil (high calorie density) contains 120 calories, whereas you’d need to eat four cups of broccoli (low calorie density) to consume the same calories. Likewise, 85 grams of steak has the same calories as an entire cup of lentils.

As a very general guide, when looking at your average day of eating on a plate, fill half your plate with vegetables and fruits and the other half with wholegrains, starchy vegetables (such as potato, sweet potato, pumpkin, and peas), and legumes (such as lentils, beans, and chickpeas). Nuts, seeds, herbs, and spices can be used in smaller quantities for additional flavour and texture. Switching from more refined and calorie-dense foods to whole plant foods often leads to effortless and hunger-free weight loss. However, if you feel more tired, hungry, or potentially start losing weight you don’t want to, it can be helpful to increase portions of healthy, more calorie-dense plant foods, such as legumes, wholegrains, nuts, and seeds.

SMART SWITCHES

Let’s consider the healthiest plant-based alternatives for a few common items you’ll be looking to replace.

MILK

Choose a plant milk with minimal ingredients, ideally containing just the main ingredient and water, free from added sugars, oils, additives, preservatives, or synthetic vitamins and minerals.

CHEESE

Blitzing nuts, seeds, or even oats can substitute for parmesan, especially if you add in some herbs and spices. Nut and seed butters, such as cashew or sunflower, can substitute for soft cheeses in recipes when thinned out with water. Just remember, nuts and seeds are high in fat, so be mindful of portion sizes. Home-made hummus, blended beans, and sauces made with potato, carrot, pumpkin, or cauliflower can also make delicious cheese-like sauces.

ICE CREAM

Try frozen banana, mango, and other fruit blends to make a sweet dairy-free dessert.

MEAT

Some vegetables can provide the chewy, meat-like texture many people are used to – mushrooms are a great example, especially shredded oyster or king oyster. Beans and other legumes work well to provide the ‘filling factor’ that meat often contributes to meals. This works perfectly for many family favourites, including bolognese, tacos, and burger patties. Grains such as quinoa, buckwheat, and oats can also be a substitute for minced meat.

SEAFOOD

Artichoke hearts, jackfruit, and banana blossom can provide the ‘flaky’ texture in seafood dishes, while adding a small amount of dried celery, seaweed, lemon, or dill can give the right flavour boost.

NUTRIENT KNOW-HOW


You might have questions or even preconceptions about meeting your nutritional needs when switching to a WFPB nutritional pattern. The reality is, calorie for calorie, those eating animal-free diets typically get higher intakes of nearly every nutrient – fibre; vitamins A, C, E, and B; folate; potassium; and minerals like calcium, magnesium, and iron. WFPB eating also comes with dramatically less sodium and saturated fat, and no dietary cholesterol. A well-designed plant-based nutritional plan is
appropriate for all ages and all stages, including children, athletes, the elderly, and during pregnancy. Despite this, common myths remain. Let’s debunk a few.

PROTEIN

Protein is the number one nutrient of concern for many, and typically of the least concern for medical professionals skilled in WFPB nutrition. Plant-based dietary patterns, especially wholefood plant-based dietary patterns, easily contain more than sufficient protein, and also come packed with other health-promoting nutrients. For example, one cup of cooked lentils comes with 22 grams of protein, 2 milligrams of iron, and 18 grams of fibre. On the other hand, a 100 gram serve of beef has a similar
amount of protein and iron, zero fibre, and also comes with 12 grams of saturated fat. The common myth that plant foods need to be combined or complemented to meet our protein and amino acid requirements has long been disproven. We can easily meet the requirements needed for optimal health without considering percentages or types of amino acids, protein quality, availability, or digestibility. If you are eating enough calories, you’ll most likely get all the protein you need, and well above the recommended daily requirement.

IRON

While iron deficiency and anaemia can be a real medical concern, there is no evidence that plant-based nutritional patterns increase the risk for iron deficiency, anaemia, or iron store depletion. In fact, many people consuming omnivorous diets still get much of their dietary iron from nonheme iron (or plant-derived iron sources). Too much iron, especially too much heme iron (from animal flesh), actually translates to an increased cancer risk, so the optimal goal is adequate iron, not excess. Guidelines suggest men and postmenopausal women require approximately 8 milligrams of iron per day, menstruating women require approximately 18 milligrams per day, and pregnant women have the highest requirements at around 27 milligrams per day. To put this in context, a breakfast of one cup of oats, lunch of a baked potato topped with one cup of beans and with leafy greens, dinner of a lentil and kale soup, and a snack of a half cup of raisins and nuts would provide over 30 milligrams of iron. To optimise absorption, consume iron-rich foods with a source of vitamin C, such as citrus, strawberries, capsicums, or tomatoes.

CALCIUM

Dairy consumption is not associated with stronger bones, despite the high levels of calcium it contains. Only about 30 percent of the calcium listed on the label for cows’ milk will actually be absorbed and used by our bodies, compared to 50 percent of the calcium in a plant food like bok choy. The recommended daily intake for calcium in most Western countries is 1,000–1,300 milligrams per day. However, the World Health Organization recommends a much lower intake of 400–500 milligrams, noting that calcium needs increase with increased intakes of animal protein and sodium. Therefore, calcium recommendations in Australia are likely excessive for those enjoying a healthy wholefood plant-based diet. Regardless, there are plenty of nutritious plant sources of calcium to ensure sufficient intake – oranges, almonds, beans, greens, tahini, and chia seeds.

WHAT ABOUT SUPPLEMENTS?


Besides vitamin B12, there are no specific supplements necessary for those following a WFPB nutritional pattern beyond those recommended for the general population. However, standard nutrients of consideration (such as iron and vitamin D) should be tested and included via supplementation if they cannot be gained through diet and lifestyle alone. Supplementation with vitamin B12 (also known as cobalamin) is recommended for people following a plant-based diet. It is required for normal blood function and neurological health, and deficiency can be serious. B12 deficiency is relatively common in the general population, not just in those following plant-based nutritional patterns. Fortunately, we can all safely maintain adequate B12 levels by supplementing and
having our levels checked annually by an MMA blood or urine test (as opposed to a serum vitamin B12 blood test). Nutritional needs can vary throughout our lifespan, such as during childhood, pregnancy, or later in life. It is always best to discuss nutritional needs and supplementation recommendations with your healthcare provider, regardless of your dietary habits. WFPB nutrition is a simple way of eating that can certainly be delicious and will definitely deliver health benefits. Over time, you will be happy to skip the processed foods and head straight for the fresh produce. Give it a try and feel the difference!

This story was published in Nourish plant based-living magazine, Issue 74, with the title: Foods with benefits


This story featured in Nourish plant-based living Issue 74 • View magazine
Dr Renae Thomas
Dr Renae Thomas

Dr Renae Thomas is a family, preventive and lifestyle medicine physician with a passion for the role of nutrition, physical activity, social connections and stress reduction in disease prevention and reversal.

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The cancer consensus

Is cancer part of a genetic lottery or can prevention really begin on our plate? Dr Renae Thomas explores the role of healthy whole food plant-based nutrition as part of the cancer prevention toolkit.

When I was four years old, my father was diagnosed with metastatic cancer. This type of cancer is one that spreads from where it started in the body to other areas. Despite the fear, pain and suffering, thankfully, he has been cancer-free and healthy for 25 years since. I can now reflect on the positives that came out of this challenging time for our family, which ended up being my introduction to nutritional medicine.

I will never forget many of the awful experiences my father went through: the seemingly endless vomiting, the weight loss, losing his hair, and the pallor of his skin. He became a shell of himself from total exhaustion. But equally, I remember more amusing events, such as his lips and hands stained orange from juicing, the playful arguments we had over dinners of pureed vegetables (again!), and – much to the horror of almost everyone at that time – our transition to a plant-based diet.

I will never know for sure whether my father’s lifestyle changes contributed to his cancer recovery, subsequent remission, and relapse prevention. However, he was always very conscious of basing his choices on the best scientific evidence available. The emerging research that continues to be published remains founded on the same principles – that preventing many of the chronic diseases that still plague us today has a strong relationship with nutrition.

What are the chances?

Cancer has become a deep-rooted fear for much of the world’s population. This is not without reason, given cancer is the second leading cause of death globally. Every year, approximately 17.5 million people receive a new diagnosis of cancer, a figure predicted to increase by about 70 percent by the year 2030.

And, it’s not simply a lottery of genetics. The American Institute for Cancer Research estimates that around 40 percent of cancer cases are preventable. This means about seven million cases of cancer could be prevented every year by optimising controllable cancer risk factors – including nutrition.

It is estimated that one in every three cancers may be directly associated with sub-optimal dietary intake. What we eat represents a multiple-times-per-day environmental exposure that varies greatly between individuals. This is why dietary differences and their relationship to cancer have been extensively studied.

Nutrition research has been broadly divided into two categories: dietary exposures related to increased cancer risk and dietary exposures that may have a protective effect against the development of cancer.

The bad news first

Much of the evidence we currently have suggests that diets high in animal products and low in plant-based foods increase the risk for cancer development, recurrence, and risk of dying from cancer. This evidence is consistent with results generated by numerous meta-analyses and systematic reviews as well as with large research studies of various populations worldwide. Here is what the research tells us about cancer and animal products.

High intakes of animal protein have been associated with increased risk of cancer mortality. Many known (class-1) and probable (class-2) carcinogens can become concentrated in animal products, especially those higher in fat. Consumption of these increases exposure to many environmental toxins and pollutants, including pesticides, herbicides, insecticides and heavy metals.

The World Cancer Research Fund states that both unprocessed and processed red meats can increase inflammation and cellular stress, and increase exposure to compounds such as nitrites. For example, every 50 grams of processed meat consumed per day (such as one hotdog or two slices of ham) is associated with an eight percent increase in the risk of dying from cancer.

‘Meat-cooking-related mutagens’ (Heterocyclic Amines and Polycyclic Aromatic Hydrocarbons) are classed as known carcinogens. These are found in well-cooked meat, poultry and fish products, in pan drippings, and in any meat surface that is browned or chargrilled.

Eating seafood and white meats is also associated with increased exposure to many known carcinogens, including heavy metals, added hormones, antibiotics, and plastics.

High intakes of dietary fat and cholesterol are associated with increased risk for cancer. Animal products contribute to much of this in the standard Western diet. Just half an egg, one and a half serves of dairy, and 125 grams of meat, poultry or seafood per day exceeds the maximum recommended intake of dietary cholesterol.

It’s also important to understand that some typically plant-based foods can also increase cancer risk. These include ultra-processed foods, alcohol, carbonated beverages, and excess refined carbohydrates.

So, what’s the good news?

There are specific foods associated with decreased cancer risk, and the ones with the most consistent evidence are plant-derived. Let’s look at the benefits of plant foods according to the research.

  • Plant foods are high in substances known as phytochemicals, which have antioxidant properties that reduce stress on DNA and can protect cells from turning into cancer.

  • Plant foods are the only source of fibre in human diets, with numerous large studies providing evidence that higher fibre intake is associated with reduced risks for many types of cancer.

  • Wholegrains contain a vast variety of substances that can be protective against cancer formation, including fibre, vitamins and minerals, healthy plant chemicals, nutritious plant fats, and antioxidants. These can support cell, gene and hormonal functions, while reducing inflammation, cholesterol and cellular stress.

  • Fruits and vegetables similarly contain many health-promoting compounds, such as fibre and antioxidants, which help protect and detox DNA, cells and enzymes from stress and damage. Cruciferous vegetables (such as broccoli, cauliflower, cabbage and kale) are particularly powerful for cancer prevention.

  • The anti-cancer properties of nuts and seeds include many compounds that have been found to support healthy cell function and growth, and also suppress many cell functions that may lead to cancer. Nuts and seeds are also high in fibre, vitamins and minerals, anti- inflammatory substances, and healthy fats – many of which have been associated with a decreased cancer risk.

  • Numerous studies have documented the antioxidant, anti-inflammatory, and immune-boosting effects of herbs and spices. Research suggests they may enhance prevention and treatment of several cancers by supporting healthy cells and DNA, preventing the growth and spread of cancer cells, optimising hormones, and making cancers more responsive to treatments including radiotherapy and chemotherapy.

Healthy fruit and veg

What we eat matters

The general consensus of all scientific research is that the processes of cancer and its treatment, remission and recurrence are highly complex, with significant interaction between human genes and environmental exposures.

Excitingly, there is a growing body of high-quality evidence that suggests cancer risk reduction strategies can lie in the foods we eat each day. While there are no guarantees or absolutes, it does appear that for many (like my dad), a shift towards eating more plants and less animal products can have a protective effect against cancer development.

What we eat can even enhance treatment response, raise the chances of full remission, and help avert the likelihood of cancer recurrence. This information is incredibly empowering for the global fight against cancer. But it gets even better, as the science also shows eating more whole plant foods is protective against many other chronic diseases such as type 2 diabetes and cardiovascular disease. Much of this evidence exists on a spectrum, meaning it doesn’t have to be all or nothing. Every step in the right direction can be celebrated, because each healthy choice contributes towards improvements.

In no way do I suggest a plant-based diet is a substitute for medical care; there are no ‘miracle cures’. However, I am confident that the peer-reviewed scientific research that has fascinated me since childhood shows us nutrition plays a powerful role in health and disease prevention.

It brings me great satisfaction to have a nutrition prescription in my tool kit to help support my patients. This information can be applied in an attainable and sustainable way for those with a diagnosis as much as it can by those who wish to minimise risk. In short, my research and experiences have taught me to eat more plants… and that Dad is always right!


This article is an edited extract from Nourish plant-based living, V8 N5 • View magazine
Dr Renae Thomas
Dr Renae Thomas

Dr Renae Thomas is a family, preventive and lifestyle medicine physician with a passion for the role of nutrition, physical activity, social connections and stress reduction in disease prevention and reversal.

Enjoying our inspiring stories? We always love to hear from you with suggestions for the content you want more of. Suggest a topic here.

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YOUR INPUT