Sustainability is a multifaceted issue, in which the food production system and our diets play a crucial role. The word “sustainability” itself can be hard to define as it can mean different things, depending on the context in which it is discussed. Even though the concept of sustainable diets is not something new, it is more complicated than a trending buzzword. For example, last week we discussed why changing diets is hardly sustainable, or hardly adopted for a long time, though changing to a sustainable diet over a longer period of time is better than having a drastic change for a short time.
After discussing the health aspect of diet, we need to remember how diet is closely related to the environment. As we will refer to it for the rest of this article, sustainability means the enactment of practices that fulfill the needs of society while protecting the physical basis of our long-term survival, our environment [14]. As put forth by the U.N.’s Brundtland Commission on sustainable development in 1987: “Sustainable development [meets] the needs of the present without compromising the ability of future generations to meet their own needs” [12].
By those definition, we cannot talk about having a secure food supply unless that food supply is sustainable. All food systems, from the primary production of the food to when it is consumed, rely in some way on natural resources such as water, fertile soil, and biodiversity. Food systems currently account for about 30% of the world’s energy consumption and over 20% of total greenhouse gas emissions (GHGE) [6].
Changes to more sustainable dietary patterns hence are needed in order to reduce the environmental burden. In doing so, nutritional cultural, social, and economic aspects also need to be considered, without neglecting the environmental aspect. However, it is important to note that an environmentally-friendly diet is not necessarily healthy, and vice versa.
Why do we need to care about sustainable food supply?
We live in the world where more than three billion people are malnourished and many of our planet’s 7 billion inhabitants eat low-quality diets. At the same time, the world’s population is rapidly expanding, and this number is estimated to reach 10 billion people by 2050. When talking about sustainable food development, the goal is to ensure a future when this expanded population has both enough food available to eat and access to high quality, nutritious foods.
Human activity of agriculture has become the largest cause of global environmental change. Examples of global environmental change include climate change, deforestation, desertification, and damage to coastal reefs and marine ecosystems. Also, food production:
Contributes approximately 30% of global greenhouse gas emissions, and the livestock sector alone represents almost half (14.5%) of these emissions [7, 14],
Occupies about 40% of global land [4],
Uses 70% of freshwater supply
Is the largest factor threatening endangered species to extinction [13]
Causes eutrophication (nutrient overload) and dead zones in lakes and coastal areas [3]
Has led to a majority (~60%) of the world fish stocks to be fully fished or overfished (33%) – only 7% are underfished [5].
Such global environmental change increases the risk of irreversible and catastrophic shifts in the Earth system marked by rising human mortality, morbidity, conflict, and food insecurity. This is the time we need to rethink the way we produce and process food. The simplest action could start by changing our habitual diet.
What makes a diet sustainable?
To this day, no consensus as to what constitutes a sustainable diet. While the concept of sustainable diet is not new, it remains a complex issue.
Most studies support that there are environmental benefits to increasing the consumption of fruits and vegetables, while reducing the consumption of animal-based foods [8, 11]. However, the majority of studies have only looked at GHGE (a marker for climate change) as an indicator of environmental impact. A growing evidence suggests that a diet low in meat and high in fruits and vegetables may not even have a lower environmental impact because of the amount of vegetable substitutes that need to be consumed to replace animal protein and calories [11, 15]. Vieux et al. [15], found that replacing meat and deli meat by fruits and vegetables to achieve the same energy intake gave a null effect, or even increased GHGE. Thus, in addition to climate change, the effects on various other aspects of the environment, such as land use, water footprint, energy or fossil use, also need to be considered. Furthermore, other aspects of sustainability also need to be taken into account, including social and economic factors, as well as nutrition and health.
Several issues that need to be taken into account regarding plant-based diets:
A strict plant-based diet may not be optimal as it would require a substantial shift in typical food choices and it poses nutritional risks; such as deficiency in vitamin B12 and some minerals
Vegetables and grains require higher-quality land with restricted availability, while certain areas have more lower-quality land, which is suitable for forage crops, not for human consumption;
Most studies indicate that animal-based foods generate more GHGE than plant-based foods, but this does not apply to fruits and vegetables grown in greenhouses;
Sustainable and certified produce tends to be more expensive, which is a barrier to accessing a healthy, sustainable diet.
Healthy eating plate
You can use the healthy eating plate (Figure 1) as a guide for creating healthy, balanced meals – whether served on a plate or packed in a lunch box. You can put a copy on your refrigerator to serve as a daily reminder.
Figure 1 The graphical guideline to the healthy eating plate, comprises half of fruits and vegetables, a quarter of whole grain, and healthy protein on the remaining quarter.
Make most of your meal vegetables and fruits – ½ of your plate:
Aim for color and variety and remember that potatoes don’t count as vegetables on the Healthy Eating Plate because of their negative impact on blood sugar.
Go for whole grains – ¼ of your plate
Whole and intact grains – whole wheat, barley, wheat berries, quinoa, oats, brown rice, and foods made with them, such as whole wheat pasta – have a milder effect on blood sugar and insulin than white bread, white rice, and other refined grains.
Protein power – ¼ of your plate
Fish, poultry, beans, and nuts are all healthy, versatile protein sources – they can be mixed into salads, and pair well with vegetables on a plate. In 2016, FAO endorsed higher beans and legumes consumption not only because of its potential health benefits, but also its benefit on agricultural, farmers’ welfare, and land quality. Limit the consumption of red meat and avoid processed meat, such as bacon and sausage.
Healthy plant oils – in moderation
Choose healthy vegetable oils like olive, canola, soy, corn, sunflower, peanut, and others, and avoid partially hydrogenated oils, which contain unhealthy trans fats. Remember that low-fat does not always mean healthy. Also, consider the environmental impact of such oils. As an analogy, palm oil has less GHGE than other oils, but we also need to consider its effect on deforestation, forest fire, and the loss of rainforest ecosystem, especially on the endangered species.
Reduce consumption of packaged food
Besides taking a lot of resources and packaging, these foods are especially rich in sugars, fats, and salt, as indicated in the nutritional information labels. Hence, they are not considered sustainable foods for your health and the environment.
Use fresh ingredients whenever possible
This helps reduce needless packaging waste, at home and when eating out. It offers another way to favor a sustainable diet, reducing the environmental impact of food production and distribution
Prefer seasonal, local products
Knowing your local food not only enables you to buy the freshest and tastiest food at a lower cost, but is also key to sustainable agriculture and a circular economy.
Buy fish from sustainable sellers
For the seawater fish, it helps to protect marine ecosystem, increasingly threatened by overfishing and destruction of coral reef. Consumption of freshwater fish responsibly fished or farmed would also minimize the environmental impact.
Look for products from sustainable sellers and producers
It may be not easy as you need to take an extra effort to recognize the food producers and sellers, Consumer choices also have an impact on the quality of life of the animals we use for food. Also, this careful consideration would impact our health, e.g., when we choose meat produced without hormones or antibiotics.
Drink water, coffee, or tea
Skip sugary drinks as we don’t need extra calorie from our drinks. Limit milk and dairy products to one to two servings per day, and limit juice to a small glass per day.
Stay active
The red figure running across the Healthy Eating Plate’s placement is a reminder that staying active is also important in weight control, as eating healthy diet alone is inseparable from other aspects of healthy lifestyle.
Other factors to consider regarding sustainable diets
Other than the composition, the portion size becomes an issue. Over-consumption of food has detrimental effects on both the environment and health. Over-consumption places an unnecessary increased demand on food production, resulting in higher GHGE [9].
Also, food waste at the retail and consumer levels is an important issue, particularly in developed countries (Reisch, 2013). Food is wasted along the entire food supply chain and has been estimated to account for 10% to 40% [1].
If you are looking for some ideas to prepare a meal plan that is healthy for you and the environment, you can find an example here:
S.A.D Team
References
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