Author: Dr Renae Thomas, MD
The increasing media attention on plant-based nutrition means that there is a lot of conflicting advice out there. This can make simple concepts unnecessarily complex. We have invited Dr Renae Thomas, a Family and Preventive Medicine Resident who resides in the Blue Zone Loma Linda, California, to help clarify how we can all optimise our chances of achieving optimal health and longevity based on evidence-based research. Dr Renae’s impressive academic resume and passion for empowering people to make healthy lifestyle choices help her break things down in simple terms. In this article, she explains to us the meaning of Lifestyle Medicine, Blue Zones, the fascinating Loma Linda, how to make sense of Adventist Health Studies, and how best to adopt a whole-food, plant-based nutritional pattern. Are you ready to get the most out of your body?
What is a Blue Zone?
Popularized by Dan Buettner, a Blue Zone represents the areas in the world that are living the longest, with the greatest populations of centenarians, or those living to, and into, their hundreds. The most impressive part is that these populations are not only achieving a long life, but are living healthily and actively into old age, with minimal diseases or health problems. The five countries focused on are the Barbagia region of Sardinia, Ikaria in Greece, Nicoya Peninsula in Costa Rica, Okinawa in Japan, and Loma Linda in California.
Researches came together to found the power-9; nine characteristics shared between these places, suggested to contribute to their good health and longevity. These include moving naturally (walking, gardening and playing), living with purpose, having a sense of belonging, downshifting/stress management, connecting with loved ones, having the right tribe and eating predominantly plant-based (at least 95% nutrition from plants, and 5% or less from animal products).
The final two, drinking wine at 5pm and eating to 80% full, I personally disagree with. As alcohol is a class one carcinogen as per WHO and IARC monographs, it is known to cause cancer in humans. In terms of eating to a certain percentage, I believe that we should trust our body’s true hunger and satiety signals and try not to restrict food, especially when eating nutritious plant-based foods. Overall, however, the power-9 creates a great foundation for building optimal health similarly reflecting the principles of Lifestyle Medicine.
What is Lifestyle Medicine?
From the American College of Lifestyle Medicine, Lifestyle Medicine is described as “the use of evidence-based lifestyle therapeutic approaches, such as a plant-predominant dietary lifestyle, regular physical activity, adequate sleep, stress management, avoiding the use of risky substances and pursuing other non-drug modalities to treat, reverse and prevent chronic disease”.
The focus here is using scientific evidence collected from numerous peer-reviewed studies, to find trends and patterns in the way that people thrive all over the world in order to work towards a lifestyle for the individual that is easy and enjoyable, but also optimizes health and longevity. It is not necessarily a replacement for medicines and procedures in every case, but provides you with the best chance to live optimally and healthily.
What is special about Loma Linda?
Loma Linda, in California, is the only Blue Zone in the United States, and in fact, the only Blue Zone in the US, UK, NZ, and Australia combined! Loma Linda has been extensively studied as the population, predominantly Seventh Day Adventists, are considered a ‘health-conscious’ population. With the majority having strong faith and family values, long-lasting community connections, a physically active life, they also have minimal rates of tobacco smoking and alcohol consumption, a focus on stress reduction (including their Sabbath, where full rest and disconnection from technology and work is encouraged). Vegetarian nutrition is encouraged, yet even in those who do consume animal products, it is less than 5% of food intake for meat, and less than 10% for dairy products and eggs.
What can we learn from the Adventist Health Studies?
Whilst the majority of lifestyle factors above are followed by the majority of Adventists living in Loma Linda, the aspect that varies the most is the nutritional pattern, with about 50% consuming an omnivorous diet (including animal products, though still in relatively small amounts compared to the average American), about 25% consuming a vegetarian diet (with varying amounts of dairy and/or eggs included) and about 25% following a fully plant-based or ‘vegan’ nutritional pattern. As many typical confounding factors for health in studies, such as physical activity, smoking, alcohol consumption, economic status, culture and social support levels are relatively consistent through the population, it sets up a pseudo-controlled trial to study the impacts of different nutritional patterns.
What we see is that for almost every disease studied, including all-cause mortality, cancer, diabetes, high blood pressure, heart disease, obesity, inflammatory and auto-immune conditions, and degenerative conditions such as arthritis, there is usually a significant association and stepwise progression towards prevention of diseases, and optimization of health, as one moves closer and closer towards a plant-based nutritional pattern. In simple terms, the more plants one consumes, the less likely they are to develop diseases and disabilities, and the more likely to live longer in good health.
What is a Whole-food Plant-based Nutritional Pattern?
Whole-food Plant-based nutrition grew out of many of the large studies, such as EPIC-OXFORD, the Adventist Health Studies, and other large cohort studies on nurses and physicians, keeping track of what thousands of individuals ate over many years, and how their states of health were at various intervals. This created many patterns of evidence for nutritious food choices, and even inspired a few clinical trials to prevent and reverse diseases, such as Dr. Dean Ornish’s research in heart disease and prostate cancer, Dr. Caldwell Esselstyn’s work on cardiovascular disease, Dr. Neal Barnard’s work on diabetes, and Dr. Luke Wilson’s work on sustainable weight loss, to name a few.
A whole-food plant-based nutritional pattern, in its most simple form, is consuming an abundance of fruits, vegetables (including starchy vegetables such as potatoes), intact wholegrains (such as oats, quinoa, millet, whole-wheat, brown rice, and barley), and legumes (including chickpeas, split peas, lentils, and beans), herbs and spices, with moderate amounts of nuts, seeds, avocadoes, olives and other higher-fat plant foods. The whole-food plant-based nutritional pattern minimizes and preferably eliminates intakes of animal products including red and white meats, dairy products (milk, cheese, yoghurt, ice-cream, cream, butter etc.) and eggs.
The whole-foods plant-based nutritional patter is also ideally free from, or low in added salt, sugar, oils, artificial sweeteners and processed/refined foods. Whilst that may sound a little intimidating if it is drastically different compared to how you currently eat, just know that there is good evidence for taking just small steps, making 1-2 switches for healthier ingredients, or just adding one healthy choice in. The goal is to find a way of eating that is supported by scientific evidence, and incorporating it into your life in a way that is simple, enjoyable, low-stress and sustainable.
So, what does this even look like?
Whilst a quick google search these days yields thousands of recipes and an abundance of plant-based recipes found on Plantd, an example of a plant-based day follows:
- Breakfast: Oatmeal made with almond milk and topped with fruit and a sprinkle of seeds
- Lunch: Baked sweet potato topped with balsamic kale and beans, and a salsa-avocado mix
- Dinner: Brown rice bowl topped with favorite vegetables and a lemon-tahini-herb sauce
- Snacks: Fresh fruits, nut/seed mixes
*Dr Renae Thomas, MD, B-BMed (Nutrition and Exercise Physiology), MBBS (Honours), is an Australian-born, Family and Preventive Medicine Resident, in Blue Zone Loma Linda, California. Renae is completing a masters in Public Health (Population Medicine), is a published co-author on vegetarianism and cancer, an international speaker on nutrition and health, has completed an internship at True North Health Centre in 2016, is the co-Vice President of the American College of Lifestyle Medicine Trainees, is on the lifestyle track committee for the American College of Preventive Medicine, is a PCRM (Physicians Committee for Responsible Medicine) spokesperson, a McDougall Starch Solution and Dietary Therapy graduate, and a qualified yoga teacher.