After many have already adopted vegetarianism or veganism, it is the turn of the medical establishment. Studies from recent years prove not only that a plant-based diet does not cause nutritional deficiencies as thought, but it is also more effective in preventing heart disease and cancer and balancing high cholesterol and diabetes
At the end of 2017, the American “Vogue” crowned veganism as the hottest trend in the wedding industry for this year. “Without a doubt, we are seeing more brides and grooms choosing vegan options,” declared the article in the magazine, citing leading wedding planners in the United States. And they are not the only ones who think so.
Even before the year 2018 began, international catering and food delivery chains such as International Meal Delivery Service and Just Eat and food and restaurant consulting companies such as Baum Whiteman declared that the hottest megatrend expected for 2018 in the field of nutrition is veganism – Pure plant-based diet, without meat, fish, dairy products and eggs.
This trend, as “Vogue” well identified, was very hot already in 2017, with an increase in the availability of a variety of vegan foods and vegan versions of different foods on the shelves and vegan food options in restaurants. In fact, according to a report published by the British marketing research agency Mintel at the end of 2016, it started long before that, with an increase of 257%) in sales of vegan food products compared to the years 2010-2011
“In my opinion, it is more correct to call the growing preference for veganism a trend rather than a trend,” points out Orit Ofir, a clinical dietitian at Atid, the association of dietitians in Israel. “The word ‘trend’ has a connotation of something temporary and passing, and veganism is undoubtedly not a passing trend. It is clearly a trend that is consistently rising.” This is exactly what Mintel’s report states, according to which “the preference for a natural, simple and flexible diet will lead to a continued expansion of veganism, vegetarianism and plant-based combinations”.
Even in Israel, awareness and demand for vegan food products is growing rapidly. Although there is no systematic collection of data in Israel by official bodies that can indicate a change in trend in the field, but according to a survey conducted by the Panels Research Institute in 2014, more than 400 thousand Israelis (approximately 5%) defined themselves As vegans, more than 640 thousand (about eight percent) defined themselves as vegetarians, and more than a million (about 13%) said they were considering becoming vegetarians or vegans.
Also, 23% reported that they reduced their meat consumption in the past year, and about 18% reduced their consumption of dairy products. The data in the field also makes it clear that this is the case: since labeling vegan products in Israel began in 2012, there are now about 3,000 such products on the shelves. In fact, the trend with us has become so strong that it turns out that milk substitutes, such as soy and almond milk drinks, were one of the fastest growing categories in the milk market in 2017, and ironically it was this trend that saved Tnuva sales this year, when soy products and protein-enriched products helped for the company to grow stronger.
טבעונות. טרנד חם(צילום: shutterstock)
A difficult idea to digest
The two main factors driving the veganism trend are ideology and health. It seems that the ideological-moral angle is no longer required for proof, mainly due to the energetic activity of animal rights activists, led by the charismatic and provocative lecturer Gary Yurofsky .
His lecture at the Georgia Institute of Technology in 2010, in which he talked about what is happening in the meat, egg and dairy industries and described the abuse of animals, became the most watched lecture on the Internet in Israel. The lecture, and later Yurofsky’s visits to Israel in 2012 and 2013, motivated many to switch to a vegan diet or at least to reduce meat consumption.
Along with the humanitarian-moral consideration, the health factor is also a significant driver in the decision to switch to a plant-based diet, and the recent change in the medical community’s perception of veganism and vegetarianism can be defined as nothing less than a revolution, although this transformation was gradual and lasted for several decades.
For example, in a new research review published in the journal Critical Reviews in Food Science and Nutrition, a team of Italian researchers conducted complex statistical analyzes on the results of 86 cross-sectional studies in which they compared data at one point in time collected from 56,41 vegetarians, 8,421 vegans and 184,186 omnivores aged 18-81, as well as the results of ten longitudinal studies that followed 72,298 vegetarians for 4-21 years. The findings of the review show that compared to an omnivorous diet, a vegan and vegetarian diet leads to a significant decrease in BMI- and cholesterol and blood sugar levels, and also has a significant protective effect against morbidity and mortality from heart disease and cancer.
In the review, it was found that a vegetarian diet reduced the risk of incident and death from ischemic heart disease by 25% and the risk of cancer by 8%, and that a vegan diet is associated with a 15% reduction in the risk of cancer.
תזונה צמחונית הפחיתה ב-%25 את הסיכון להיארעות ותמותה ממחלות לב (צילום: shutterstock)
The idea that a vegan or vegetarian diet could help prevent disease and mortality was not easy for the scientific community to digest. In fact, when the first position paper of the American Academy of Nutrition and Dietetics (ADA) on the subject was published in 1996, its focus – as well as most of the studies conducted at that time – was on the question of whether a vegetarian diet, and certainly a vegan diet, is safe for consumption and meets the requirements the nutritional
But the many studies that have accumulated over the years that followed have consistently and persistently indicated that a plant-based diet is indeed safe and meets the nutritional requirements. “These studies helped dispel concerns about nutritional deficiencies, and as a result, the researchers moved to the next stage of research in the field – to check if a vegan and vegetarian diet also has health benefits,” Ofir explains. “Indeed, the studies conducted in the last 25 years provide impressive scientific evidence indicating that a vegetarian diet, and especially a vegan diet, has an advantage in preventing diseases of the age of abundance, such as diabetes , cardiovascular diseases, and also various types of cancer.”
One of the famous early studies that pointed to the benefits of a plant-based diet in preventing diseases of the Age of Plenty is the China Study, the comprehensive dietary survey conducted by Cornell University, the University of Oxford and the Chinese Academy of Preventive Medicine led by biochemist and nutritionist Colin Campbell. The study, described in Campbell and his son Thomas’s book “The China Study” (published in 2004), was conducted among 6,500 people in 65 provinces in China over two decades and found significant statistical correlations between lifestyle, diet and disease.
Along with the China study, many other scientific studies were presented in the book that also found a connection between animal nutrition and the occurrence of diseases. “Additional studies conducted later indicated that vegans and vegetarians are at a lower risk of developing diabetes, and some studies indicate a two-fold reduction in risk,” Ophir says. “It was also found that among vegans and vegetarians the rate of cancer is lower than in the general population, especially prostate cancer and colon cancer.”
Continuous perceptual change
Following these findings, the ADA published in 2009 a position paper which concluded that a properly planned plant-based diet, including a vegan diet, has been proven to be healthy, and that it meets the nutritional requirements, is suitable for all stages of life and can also be useful in preventing certain diseases. At the same time, other leading organizations also began to emphasize the importance of plant-based food in preventing disease.
Thus, in 2012 the American Cancer Society (ACS) published nutritional guidelines for cancer prevention recommending a “balanced diet, with an emphasis on plant foods” and reducing the consumption of processed meat and red meat. The association’s guidelines also clarified that the consumption of soy foods such as tofu can apparently reduce the risk of breast, prostate and endometrial cancer. This is a clarification that is a revolution in itself, since until the last few years soy was considered a controversial food that was suspected of being a factor that could actually accelerate hormonal cancers and cause negative effects on children’s growth. In this case too, what changed the picture were the many studies carried out in the last decade, which showed that there is no basis for this fear, and that in fact the opposite is true.
But the culmination of the change in the scientific community’s perception was marked by the latest position paper published by the American Academy of Nutrition and Dietetics in 2016. different,” says Ophir. “This is actually the third stage in the development of understanding in relation to a plant-based diet. If the first phase focused on the issue of meeting the nutritional requirements and the second on the question of whether this diet can help prevent diseases, then at the forefront of research today is the question of whether it may also have a therapeutic effect, that is, whether it can really help in treatment and healing.
For example, there are studies that have shown that beyond a vegan diet compared to an omnivorous diet, a vegan and vegetarian diet leads to a significant decrease in BMI and cholesterol and blood sugar levels, and also has a significant protective effect against morbidity and mortality from heart disease and cancer “The studies conducted in 25 – The last few years provide impressive scientific evidence indicating that a vegetarian diet, and especially a vegan diet, has an advantage in preventing diseases of the age of abundance, such as diabetes, cardiovascular diseases, and also various types of cancer,” Ophir says.
איזון רמות הסוכר באופן יעיל ובהורדת מינון התרופות(צילום: shutterstock)
Type 2 diabetics achieved better results in lowering sugar levels than a diet based on the guidelines of the American Diabetes Association, and it even made it possible to reduce the dosage of medications. It was also found that switching to a vegan diet achieved better results in lowering cholesterol levels compared to the diet recommended by the American Heart Association (AHA) and here, too, this was reflected in the possibility of reducing the dosage of medications.
Indeed, a research review published in the journal Cardiovascular Diagnosis and Therapy in 2014 that looked at six clinical studies found that a plant-based diet was associated with improved blood sugar control. In another study, published in 2011 in the journal Diabetes Medicine, it was found that consumption of a plant-based diet for 24 weeks led to an improvement in insulin sensitivity, a reduction in abdominal fat and a decrease in the levels of inflammatory markers compared to a menu based on the dietary guidelines for diabetics.
Another study published in the journal Diabetes Care found that switching to a low-fat vegan diet achieved better results compared to a diet based on the American Diabetes Association guidelines not only in improving sugar levels, but also in improving blood lipid levels and weight. “Compared to an omnivorous diet, and even to a vegetarian diet, the vegan diet contains greater amounts of folic acid, potassium, magnesium and dietary fiber,” Ophir explains.
“הסיבים התזונתיים מצויים אך ורק בעולם הצומח, והם ידועים בין היתר בכך שהם מקנים תחושת שובע ומסייעים באיזון רמות הסוכר והכולסטרול בדם. תזונה טבעונית גם אינה כוללת כולסטרול, המצוי רק במוצרים מהחי, והיא דלה בשומן רווי – גורם נוסף התורם לעליית רמת הכולסטרול בדם. בנוסף, היא עשירה יותר בנוגדי חמצון, בהם ויטמיני C ו-,E פלבונואידים וקרוטנואידים, שמסייעים להפחית את תהליכי החמצון המהווים גורם משמעותי בהתפתחות מחלות לב וכלי דם, סוכרת, סרטן ועוד. למשל, כיום ידוע שאחד הגורמים המרכזיים בהתפתחות טרשת עורקים הוא חמצון ה-LDL (הכולסטרול הרע). מזון מהחי מכיל כמות זניחה של נוגדי חמצון ומנגד כמות גבוהה של מחמצנים כמו ברזל”.
A diet rich in antioxidants (photo: shutterstock)
Does a vegan diet meet the nutritional needs? American Heart Association Review Highlights
Due to the concerns about nutritional deficiencies among vegetarians and vegans, and at the same time the research evidence indicating the effectiveness of this diet in the prevention and treatment of diseases, in the latest position paper of the American Heart Association, the ADA, central attention was devoted to examining the information and findings on the absorption and bioavailability of components various essentials in plant foods, such as iron, zinc, iodine, calcium, vitamin B12 and the essential omega-3 fatty acids of the EPA/DHA type
In general, these findings reinforce what has already been demonstrated in the association’s two previous position papers – that a plant-based diet does not cause deficiencies in most of the various essential components. However, some components, mainly vitamin B12 and iodine, do require supplementation through fortified foods or nutritional supplements. Here are the main points of the review: Iron: the findings indicate that our body knows how to regulate the absorption of iron from the plant according to its needs. Thus, in people with an iron deficiency, the absorption of iron from plants can be ten times higher than in people who have sufficient levels of iron. Zinc: It has been found that the levels of zinc in the blood of vegetarians are lower compared to omnivores, but are within the normal range and do not seem to lead to the attributed health problems To be deficient in zinc, apparently also in this case thanks to the body’s regulatory mechanisms. However, among pregnant and lactating women, the elderly and children, there is not enough research evidence to determine whether their zinc levels are lower compared to non-vegetarians. Calcium: Among vegetarians who eat dairy products, calcium intake often meets the dietary recommendations. However, among vegans there is great variation in calcium intake, and some are deficient in calcium. Iodine: A plant-based diet can be low in iodine, so it is important that vegans and vegetarians consume seaweed or iodine-enriched salt. Vitamin B12: This vitamin is not found in plant foods, although it is found In fermented foods such as tempeh and algae such as nori, spirulina and chlorella, these sources are insufficient. Therefore, to achieve normal levels of B12, vegans must consume foods fortified with the vitamin or its nutritional supplement.
Omega-3 fatty acids: EPA/DHA Animal foods, especially fish, contain the long-chain fatty acids EPA and DHA, while plant foods contain the fatty acid ALA, which the body converts to EPA and DHA. Since the conversion process of ALA to EPA and DHA is not considered very efficient, the concern arose that their deficiency in vegetarians and vegans could cause health damage.
However, studies show that vegetarian and vegan children do not likely experience damage to visual development or mental development, and that vegetarian and vegan adults actually experience a reduced risk of cardiovascular disease. Therefore, the conclusion of the position paper is that apparently the conversion of ALA in vegetarians and vegans to EPA and DHA is sufficient.
The explanation for this may be genetic, at least according to a new study conducted at Cornell University and recently published in the journal Nature Ecology and Evolution. According to the study, the specific genes we inherited from our ancestors have an effect on our ability to efficiently convert ALA to EPA and According to the researchers, the transition from a society of hunter-gatherers, who fed mainly on meat and fish to farmers who ate mainly plant foods 8,000 years ago, caused a change in a gene called FADS1, a gene that determines the efficiency of the conversion of ALA to EPA and DHA
Protein: the richest and highest quality source of protein in the plant world is the legume family (lentils, beans, chickpeas, soybeans, peas). Since the legumes are also an important source of iron, zinc and calcium, it is very important to make sure to consume them every day, and even more than in one meal.
In 2016, the British Ministry of Health published new nutritional guidelines in which it reversed the order of foods in the protein group to highlight legumes as an environmentally friendly protein source with health benefits – legumes now appear in first place, and only after them do fish, eggs, meat and other proteins appear.
Another source of protein is, of course, soy. The enriched soy drinks are equivalent to animal milk in their protein and calcium content, and in most cases also in their vitamin B12 content, in contrast to the other plant-based drinks (eg almonds, rice and oats) which are not a source of protein.
The author holds a doctorate (PHD.) in health communication and is a researcher at the University of Haifa
