In an era where dietary choices have far-reaching implications, Prof. Danit Shahar, of the Department of Epidemiology, Biostatistics, and Community Health Sciences at Ben-Gurion University of the Negev, aims to unravel the complex relationship between our food choices, overall well-being, and environmental impact, emphasizing the importance of healthy and sustainable diets.
"My research focuses on the association between diet and health in different age groups," she says. Prof. Shahar is pioneering new ways to assess diets, blending traditional methods with cutting-edge techniques. Her approach evaluates various food exposures, from dietary patterns and processed foods to pesticides, environmental impacts, and additives. Shahar explores how these factors influence health outcomes like obesity, diabetes, geriatric functionality, and overall nutritional status.
Prof. Shahar's research methods are holistic, assessing every part of the nutrition equation. "A high consumption of a certain product always comes at the expense of something else in the overall diet," she stresses. "And in our research, we try to put all the variables together."
Her research is breaking new ground by linking sustainable food choices with improved health outcomes. "We created a food library that covers environmental footprints based on data that was provided by one of my colleagues. Based on this work, we calculated the environmental impact of the Israeli diet and are now working on strategies for promoting a healthy and sustainable diet."
By meticulously evaluating the land use, water consumption, and greenhouse gas emissions associated with various foods, she highlights the substantial ecological footprint of our diets. "It turns out," she said, "that the Mediterranean diet, which is rich in fruits and vegetables, olive oil, and fish, and includes very little meat and dairy consumption, is extremely sustainable in terms of its emissions."
For example, Greek and Italian diets, which are based on home cooking, and are very rich in olive oil, are prime examples. "Although," she adds, "even these two cuisines also have other, less beneficial products."
One of the advantages of the Mediterranean diet is that it is low in animal products, which are characterized by very high greenhouse gas emissions. "If beef constitutes 100% on an emissions scale," she said "then the emissions related to hummus will only be 1%. This is how significant the gap is."
Israel is unique in this regard since its problem is not with meat, Prof. Shahar points out. "In Israel," she said, "the high consumption of milk and other dairy products results in substantial greenhouse gas emissions." Her goal is to find strategies to reduce these impacts without resorting to drastic measures: "We aim for gradual reductions rather than drastic measures, allowing us to observe the real impacts," she says. Her studies show that even modest dietary changes can significantly affect obesity, cognitive function in older adults, and concentration.
Prof. Shahar’s research also looks into the prevalence of ultra-processed foods in modern diets and their wide-ranging consequences, "Nutrition is simply fascinating," Prof. Shahar says. "It includes everything—after all, we all eat. It connects to everyone, and is very significant from a behavioral perspective."
"In public health," she adds, "real life is your teacher, and you are constantly learning. That is especially true in my research, where we not only study the entire field of nutrition in old age and how it affects cognitive and physical function but also every related aspect. For example, the field of ultra-processed food (UPF) was lately brought to the public's attention because of the diseases that it leads to, which are becoming ever more common."
Undergoing multiple industrial processes, ultra-processed foods are products that cannot be replicated in anyone's kitchen at home. They are often high in added sugars, unhealthy fats, and artificial additives such as preservatives, colorings, and flavor enhancers. For example, sugary drinks, packaged snacks, ready-to-eat meals, and reconstituted meat products.
Prof. Shahar is reluctant to even refer to them as 'food'. "In Hebrew," she says, "'food' is derived from the word 'feed,' evoking the idea of someone providing their body with nourishment. While UPF might replicate something that could be called 'food,' it is not nourishing in the slightest, as most of these products stray very far from real nutrition."
Not one to shy away from diving into the complexities of her field, Prof. Shahar’s foray into public health nutrition is driven by a deep curiosity about the interplay between diet, health, and the environment. "You often see that when people go on a diet, it's not just that they eat less," she explains, "but rather they change their whole way of eating—which is beneficial. They will notice how they sleep better and have more energy long before they mention anything about weight loss."
She laments the fact that more focus is placed on developing new products rather than improving the existing ones, jokingly adding that "the cucumber has no lobbyists."
"We're talking about the entire food system—starting with the sowing of the seeds, the growing of the cow, and the years until it becomes fruitful. The effect here includes everything, and even this is an underestimation because, for example, food waste is frequently omitted. The lack of knowledge has a very significant impact on the field."
"Consuming a meat substitute made from pea and beet protein will never be the same as eating the ingredients in their original form," she says. "If the factory had taken the vegetables, minced them, added a binding agent like egg or flaxseed, and fried them as they are, there would be no problem. The issue is making a product that needs to be kept in the freezer for a long time, so it must contain additional ingredients that compromise its nutritional quality."
Prof. Shahar hopes her research will have a significant impact on the broader community. By emphasizing the critical connections between diet, health, and the environment, she hopes to inspire community interventions that implement gradual changes in dietary habits, "so that everyone can know what they are eating, and not to see it as something non-consequential or elitist. It must come from a place of committing to ourselves as human beings."
Aiming to bridge the gap between dietary choices and their broader impacts, Prof. Shahar is particularly passionate about influencing young people’s eating habits as they will shape the future of our planet. "I believe in education," she concludes, "in really implementing these ideas and creating involvement and encouraging people to be proactive."
Despite the challenges, Prof. Shahar highlights her aspiration to work alongside the industry to create change—not necessarily go against it. "The goal is not to eliminate an industry; it is a part of our modern world," she exclaims. "The point is to understand what you eat so you can make informed choices. I aspire for the industry to be attentive, although these changes will inevitably cost more money, and for the public to demand that it make such changes so that the food is closer to the source."
This article was written in collaboration with Ben-Gurion University in the Negev.
The Environment and Climate Change portal is produced in cooperation with the Goldman Sonnenfeldt School of Sustainability and Climate Change at Ben-Gurion University of the Negev. The Jerusalem Post maintains all editorial decisions related to the content.