Discovering healthy food with Walter Willett

Discovering healthy food with Walter Willett

October 26, 2018

Discovering healthy food with Walter Willett

With the support of science, and in perfect harmony with the BCFN experts, the epidemiologist sheds light on present and future scenarios, and on the inseparable link between human health and that of the planet 

How can we feed the 9.8 billion people who will live on the planet in 2050 with a healthy diet, and a sustainable diet in particular? The standard answer is to increase food production, grains in particular, by 70%, but this is wrong. “This road would take us towards certain failure, linked to environment degradation, accelerated climate change and increased obesity, without resolving the problem of malnutrition” claimed Walter Willett in his speech at the International Forum on Food and Nutrition organized by BCFN in New York. Willett, who is Professor of Epidemiology and Nutrition at the  Harvard T.H. Chan School of Public Health in Boston, has been researching the link between health and food, and between food and pathology development in particular, and in his role as a member of the  EAT/Lancet Commission on Food, Planet Health, he helped the audience at the meeting understand how a healthy diet for mankind can also have an impact on the health of the planet, thus strengthening the concepts behind the Double Pyramid graphic created by BCFN.  


We often talk about a “healthy diet”, but what does it mean in practice? 

A diet is a mix of different foods. Starting from the scientific data available, we can create standard categories of foods, indicating which are most important for our health and thus identifying a healthy diet. It is essential to use terms and concepts that are as close as possible to what people really put on their plates: better to talk about chicken or beans than mentioning the single components of foods. 

In short, what is the impact of a diet and its single elements on human health? 

Today we have an incredible amount of scientific data on the issue, indicating not only which foods impact our health, but also in which direction the impact goes and how strong is its effect. For example, we know that if we substitute a source of protein with another, we can significantly influence the risk of coronary disease, with a stronger risk reduction when we substitute red meat with pulses. Fruits and vegetables are the essential components of a healthy diet and they can help reduce mortality, reaching maximum benefits when we eat the recommended five daily servings. 

How healthy are the diets we find in different countries? 

After creating the definition of a healthy diet and applying it in the global context (190 countries and regions), we became aware of the wide differences among them. The Mediterranean region has a relatively good diet, like South-East Asia, but countries like the United States or the rest of Europe adopt diets that are quite far from healthy. 

Is a healthy diet also a sustainable diet? 

Generally speaking, yes. We assessed the environmental impact of different foods, to be able to show that, for example, proteins derived from chicken or pork meat, or even fish, can have a negative impact on the planet in terms of greenhouse gas emissions. Meat from grass eating animals like cattle entails the highest emission of greenhouse gases, but other foods, like pulses, can be produced with very low levels of these gases. 

Hence, changing our daily diets and moving towards a healthy diet can impact the health of the environment? 

Once again, yes. Achieving the objective of feeding the world population with a health and sustainable diet requires changes in our production systems, our eating habits and also in the way we waste food, and all these factors are interconnected. Just look at the use of grains. In the United States, only 10% of crops go to human consumption, the remainder is used for animal husbandry (43%) or to produce ethanol (30%). The picture is completely different in China, where the diet is very different from the West: in this country more than half of the crops (51%) are for human consumption, while 'only' 32% goes to animals.

What is in store for the future? 

Projections suggest that the largest population increases will take place in Asia and Africa, poor regions where poverty and malnutrition are not the exception and few resources are available for change. It is therefore essential to work keeping all the Sustainable Development Goals in mind, even those with a more social impact, such as those on education and gender parity, or access to primary utilities like drinking water. 

The roadmap of the BCFN Foundation's International Forum on Food and Nutrition continues. The next stop for discussing healthy diet and Sustainable Development Goals will be in Milan between 27 and 28 November.

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