In an age when dietary choices have far-reaching consequences, Prof. Danit Shahar of the Department of Epidemiology, Biostatistics and Community Health Sciences at Ben-Gurion University of the Negev aims to uncover the complex relationship between our dietary choices, our overall well-being, and our environmental impact, emphasizing the importance of healthy and sustainable diets.
“My research focuses on the relationship between diet and health across age groups,” he says. Prof. Shahar is pioneering new ways to assess diets by blending traditional methods with cutting-edge techniques. His approach assesses a variety of food exposures, from dietary patterns and processed foods to pesticides, environmental exposures and additives. Shahar investigates how these factors impact health outcomes such as obesity, diabetes, geriatric functioning and overall nutritional status.
Prof. Shahar’s research methods are holistic and consider each part of the nutritional equation. “High consumption of a certain product always comes at the expense of something else in the overall diet,” he emphasizes. “And in our research, we try to bring all the variables together.”
Her research breaks new ground by linking sustainable food choices to improved health outcomes. “We created a food library covering environmental footprints based on data 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 to promote a healthy and sustainable diet.”
It rigorously assesses the land use, water consumption and greenhouse gas emissions associated with various foods, highlighting the significant ecological footprint of our diets. “The Mediterranean diet, rich in fruit and vegetables, olive oil and fish, and containing very little meat and dairy consumption, has been shown to be highly sustainable in terms of its emissions,” he said.
For example, the Greek and Italian diets, which are based on home cooking and are very rich in olive oil, are prime examples. “Yet,” he adds, “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 makes up 100% on the emissions scale,” he said, “then the emissions associated with hummus would only be 1%. That’s how significant the difference is.”
Prof. Shahar says Israel is unique in this regard because its problem is not meat. “In Israel,” he says, “high consumption of milk and other dairy products leads to significant greenhouse gas emissions.” His goal is to find strategies to reduce these effects without resorting to drastic measures: “We aim for gradual reductions rather than drastic measures, which allows us to observe real effects,” he says. His work shows that even modest dietary changes can significantly affect obesity, cognitive function and concentration in older adults.
Prof. Shahar’s research also examines the prevalence of ultra-processed foods in modern diets and their far-reaching consequences. “Nutrition is really fascinating,” says Prof. Shahar. “It includes everything; we all eat it. It connects with everyone and is very important from a behavioral perspective.”
“In public health,” he adds, “real life is your teacher and you are constantly learning. This is especially true in my research, where we examine not only the entire field of nutrition in old age and how it affects cognitive and physical function, but also all the related aspects. For example, the field of ultra-processed foods (UPF) has recently come to public attention because it is causing increasingly common diseases.”
Ultra-processed foods, which have gone through multiple industrial processes, are products that can’t be replicated in anyone’s home kitchen. They’re often high in added sugar, unhealthy fats, and artificial additives like preservatives, colors, and flavor enhancers. For example, sugary drinks, packaged snacks, ready-made meals, and reconstituted meat products.
Prof. Shahar hesitates to even call them ‘food.’ “In Hebrew,” he says, “‘food’ is derived from the word ‘nourishment,’ which conjures up the idea of providing nourishment to one’s body. While UPF mimics something that could be called ‘food,’ most of these products are so far removed from real nutrition that they provide not the slightest bit of nutrition.”
Not one to shy away from delving into the complexities of his field, Prof. Shahar’s foray into public health nutrition stems from a deep curiosity about the interaction between diet, health, and the environment. “When people go on a diet, it doesn’t just mean eating less,” he explains, “but instead you find that they change their entire way of eating, which is beneficial. They’ll notice that they sleep better and have more energy long before they’ll say anything about weight loss.”
He laments the greater focus on developing new products rather than improving existing ones, and humorously notes that “cucumbers have no lobby.”
“We’re talking about the entire food system, from the seeds being planted to the years it takes to raise the cow and produce fruit. The impact is all-encompassing, and even that’s an underestimation because food waste, for example, is often overlooked. Lack of information has a huge impact on the field.”
“Eating a meat substitute made from pea and beet protein will never be the same as eating the ingredients in their original form,” he says. “If the factory took the vegetables, chopped them up, added a binding agent like egg or flaxseed and fried them as is, there would be no problem. The problem is making a product that has to be stored in the freezer for a long time, so it has to contain additional ingredients that compromise its nutritional quality.”
Prof. Shahar hopes his research will have a significant impact on the broader community. By highlighting the critical connections between diet, health and the environment, he hopes to inspire community interventions that implement gradual changes in eating habits, “so that everyone knows what they’re eating and doesn’t see it as something unimportant or elitist. It has to come from a sense of connectedness to ourselves as human beings.”
Aiming to bridge the gap between dietary choices and their wider impact, Prof. Shahar is particularly passionate about influencing the eating habits of young people, as they will shape the future of our planet. “I believe in education,” he concludes, “in actually putting these ideas into practice and creating participation and encouraging people to be proactive.”
Despite the challenges, Prof. Shahar stresses his desire to work with the industry to create change, not necessarily against it. “The goal is not to eliminate an industry; it’s part of our modern world,” he exclaims. “The important thing is to understand what you’re eating so you can make informed choices. I want the industry to be careful, but these changes will inevitably cost more money, and I want the public to demand these kinds of changes so that food is closer to the source.”
This article was written in collaboration with Ben-Gurion University of 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 retains all editorial decisions regarding content.