Dietary Guidelines for Americans 2020 – 2025 published

Read the guidelines

The USDA has released their latest dietary guidelines document, with a new emphasis on the importance of considering different life stages when designing guidelines.

A new set of dietary guidelines are designed for the US population every five years, based on the recommendations of a scientific advisory committee who review the latest nutrition and health research, ensuring up-to-date advice.

In this document, specific dietary recommendations for infants and toddlers appear, where before this advice was absent. These recommendations cover breastfeeding and infant formula use, as well as complementary foods. Strong emphasis is placed on food variety for toddlers, as well as on the importance of iron and zinc intake.

The guidelines recommend that Americans should eat more whole fruits, vegetables, and whole grains, while limiting added sugars and saturated fat to less than 10% of daily calories each. While this largely chimes with the advisory committee’s scientific report, they had suggested that only 6% of daily calories be from added sugar, due to the negative health outcomes of high dietary sugar intake. The committee were also cautious on the contentious subject of saturated fat, not recommending any change to the current guidelines and mentioning that replacement of these fats with carbohydrates is not advised.

Nutrient density and dietary patterns were pulled out as important terms in the report. Nutrient dense foods are recommended throughout, and listed as vegetables, fruits, whole grains, seafood, eggs, beans, peas, lentils, unsalted nuts and seeds, fat-free and low-fat dairy products, and lean meats and poultry. However, the recommendations put emphasis on dietary patterns rather than on individual foods or food groups to enable adaptations that fit cultural, personal and individual needs and preferences. The three food patterns of the guidelines are the Healthy U.S-Style Pattern, the Healthy Vegetarian Pattern and the Healthy Mediterranean-Style Pattern. All three patterns provide most of their energy from plant-based sources, provide protein and fat from nutrient rich sources and limit intakes of added sugars, solid fats and sodium.

This is consistent with the results of the DELTA Model which illustrates that most of our energy should come from nutrient rich foods to ensure all nutrient requirements are met. Nutrient poor foods such as sugar should be minimised, and it is essential to consider the different needs of different demographic groups.

Interestingly, the guidelines make no mention of the environmental sustainability of different foods or diets. Several countries already make this inclusion, with this number likely to increase, but it will be at least 2025 before any such recommendations appear in the US dietary guidelines.

Read the guidelines

Glossary

Photo by Louis Hansel @shotsoflouis on Unsplash

WWF encourage planet-based diet

Read the report

The WWF report Bending the Curve: The Restorative Power of Planet-Based Diets joins other efforts to demonstrate the negative health and environmental consequences of our current way of producing and consuming food, while proposing ways to turn this around.

The report opens with the assertion that our food system must provide healthy, safe, affordable and nutritious diets for all, with reference to the UN Food Systems Summit later this year and the Sustainable Development Goals. This is completely in line with the principles of SNI: nutrition must come first when considering the global food system. The report then goes on to define planet-based diets as win-wins: healthy and with low environmental impacts and explores how these can be achieved.

A major recommendation of the report is that national dietary guidelines need to be more ambitious. This echoes a results of a previous WWF model. Currently, these guidelines largely reflect a healthier version of current consumption patterns and do not consider environmental impacts. The report argues that guidelines could be simultaneously healthier and more sustainable.

The main health recommendation of the report is to increase the plant-based proportion of the diet and decrease overconsumption. This is supported by the Global Burden of Disease study findings, indicating that low wholegrain and fruit intake, as well as high sodium intake, were the greatest dietary risk factors.

Beyond these overarching directions, recommendations for dietary and production change vary on a regional level. This is due to the difference in dietary, health and environmental factors seen in different parts of the world.

Countering biodiversity loss also requires a nuanced approach. For example, the report finds that most of the biodiversity loss associated with the Danish diet is due to imports of coffee, tea, cocoa and spices. Contrastingly, red meat holds this place for Latin American countries.

Similarly, the report states that we must feed our population on existing agricultural land and not further expand, but again the implications vary by region. Countries suffering from widespread undernutrition may need to expand their agricultural land to ensure healthy diets for their population, while more developed countries may need to contract.

The same regional variability is true for the planting of trees for carbon sequestration, conversion of grazing land to arable or optimising water use. The results of the report emphasise careful consideration of actions at a national level, as healthier diets can lead to increased environmental damage of one kind or another in vulnerable regions. A one-size-fits-all approach will not lead to a sustainable food system.

Read the report

Glossary

Photo by Tomas Tuma on Unsplash

GMO crops in the global food system

Genetically modified organisms (GMO) are already major contributors to the global food system since their commercial introduction in the 1990s. For example, over 90% of US corn and soy acreage is planted with GMO seeds. Despite this, the use of GMO is still controversial, with many individuals against their use and many authorities strictly regulating their production and consumption. Here, the arguments for and against GMO use in crop production are presented. 

GMO are defined as organisms, and products thereof, that are produced through techniques in which the genetic material has been altered in a way that does not occur naturally by mating and/or natural recombination. 

The process in which GMO are created differs depending on the degree of modification required but generally, a desirable trait is identified in one organism that could be of benefit in another. The trait is studied and, if possible, the gene(s) responsible for the trait are isolated. These genes are then introduced to the target organism, either via bacterial or viral infection, where the microorganism carries the target gene into the organism for uptake, or by bombarding the organism with particles coated in the target gene. 

The outcome of the process is a GMO that expresses the desired trait isolated from the original organism. 

Advantages of GMO  

The ability to transfer desirable traits between distantly related crops that cannot be interbred has obvious benefits. Examples of GMO use include the ability to increase photosynthetic rate, develop crops that are drought-tolerant with increased yields, and produce crops with disease resistance, such as blight-resistant potatoes

Moreover, crops can be developed that have greater nutritional value than conventional varieties. There exists a long list of such biofortified crops, including cassava with increased zinc, iron, protein and vitamin A content, high lysine maize, high provitamin A rice, and corn with increased provitamin A and folate. These crops are of particular value in global regions where nutrient deficiencies are a high priority public health issue. 

One widely used GMO is Bt-maize. This crop takes its name from Bacillus thuringiensis, the bacterium that donated to the maize plant the trait of producing an insecticidal toxin. Thus, Bt-maize is more resistant to pest insects than conventional maize, leading to higher yields and reduced pesticide use. As a result, 82% of the crop grown in the US in 2020 was the Bt variety. 

Disadvantages of GMO  

The arguments against GMO are largely based on health and environmental risks. The approval process for GMO is nationally administered, so differs between countries. Largely, these processes are more rigorous than for conventional foods and assess both the health and environmental risks of the GMO. 

The World Health Organisation states that no negative health consequences of approved GMO have been shown to date. However, concerns and risks do exist. One health concern raised is the possibility of allergenicity being unintentionally transferred between organisms. An example of this was when early GMO researchers, hoping to increase methionine content, found that the main allergen from Brazil nuts retained its allergenicity after transfer into a GMO soybean. As a result, the GMO soybean was never released commercially and allergenicity is now an important consideration when selecting donor crops. 

From an environmental perspective, there is the possibility that the GMO crop itself, or the introduced gene via cross-breeding or gene transfer, could escape the farmed environment and become a pest. The implications of this would depend entirely on the nature of the GMO crop; for example, transfer of a herbicide resistance gene to a non-target organism could lead to difficulties in controlling its growth. Alternatively, GMO crops could outcompete other plants due to the introduced trait, resulting in decreased biodiversity with unknown downstream implications. While the risk of these unintended consequences is low, they should be considered in the design and management of GMO. 

Finally, some express the opinion that GMO are morally wrong, as they involve too great an interference with living organisms. Such a decision can only be weighed by the individual but will likely mean that a proportion of the population will continue to avoid foods containing GMO products. 

This avoidance is challenging given the ubiquity of GMO products in many foods and by the difficulty for a consumer in identifying GMO foods. Different authorities take different stances on GMO labelling. For example, GMO are not specifically labelled in the US, rather foods that contain ‘bioengineered’ ingredients must be labelled as such. However, specific food labelling for certain types of GMO is on the horizon. The EU has stricter rules, with a requirement for GMO ingredients to be listed on food packaging. However, major food retailers have previously been forced to change their GMO policies due to the increasing “risk of finding GM material in non-GM food”. 

Conclusion 

GMO are widespread in the global food system, but not equally distributed.  

Moreover, regulation of GMO production varies and is not always clear and explicit. There are countries, like the US, where GMO crop production is widespread. Contrastingly, 19 member countries of the European Union have previously voted to either partially or fully ban the use of GMO. In New Zealand, no GMO crops are commercially grown. These variations in use and acceptance will certainly limit investment and development of future GMO. However, there is the opportunity for countries that have a GMO-free stance to use this status to market their products at a premium. 

GMO crops generally result in decreased pesticide use, coupled with increased yields and profitability. Moreover, there are those that believe that GMO will be necessary to adequately nourish a growing population and to adapt production to changing climates. The risks of GMO largely relate to unintended and uncertain consequences that must certainly be properly managed if GMO use and development is to increase. 

This Thought for Food was written by Cody Garton, a summer intern from Pūhoro STEM academy

Glossary

Photo by Bill Oxford on Unsplash

Trends in undernourishment show promise

Read the article

A study of undernourishment in 76 countries found positive results, but not all global regions are progressing at the same rate.

Although overnutrition continues to grow globally, undernutrition rates are decreasing. Undernutrition currently affects more than 800 million people, either as protein-energy malnutrition or micronutrient deficiencies. 

The researchers used data from 1991-2013 from the FAO and the World Bank to analyse both undernutrition and related factors. The countries studied were mostly developing countries located in sub-Saharan Africa, Asia or Latin America. 

Undernourishment and child mortality showed decreasing trends overall. Urban populations, GDP, food production and agricultural land had all increased over the study period. However, when grouped into regions, the Eastern Mediterranean countries (Iran, Iraq, Jordan, Tunisia and Yemen) showed a late upwards trend in undernourishment, possibly due to political unrest in this region in the latter years of the study period. 

A problem noted by the authors is in equal distribution of food, both between countries and within national populations. This is a conclusion also reached by the DELTA Model, which shows that apart from a few micronutrients, the global food system in 2018 would have supplied sufficient nutrition for the world’s population, had it been equally distributed. The problems of unequal distribution are bound up in many other social, economic, political and environmental factors. 

While it is reassuring to see the decreases in undernourishment and infant mortality shown by this study, it also highlights areas that remain to be improved.

Read the article

Glossary

Photo by Kyle Glenn on Unsplash

Peas please

Read the article

Food Foundation in the UK are gaining traction with their ‘Peas Please: Making a pledge for more veg’ initiative, the results of which were recently described in Nutrition Bulletin. 

Despite a historically growing UK market for fruit, which has increased by around 50% since 1970, vegetable purchasing was seen to slowly decline over the same period. The common perceptions of vegetables as boring or not that tasty was likely not helped by minimal publicity, with only 1.2% of the UK food advertising spend used to market vegetables. On top of this, there are questions around the environmental impacts of the average UK shopping basket, and ample evidence that field-grown vegetables have small environmental footprints. 

Most of the UK public do not meet dietary guidelines for vegetables, particularly those with lower incomes. On top of low purchase rates, 40% of purchased vegetables in the UK are wasted at home. This matches the global trends of food waste shown by the DELTA Model, where most of the nutrient waste is from plant-sourced foods. Altogether, the nutritional and health implications of low vegetable intake due to consumer choice and waste needs to be tackled. 

The ‘Peas Please’ initiative aims to make eating vegetables more healthy, affordable, sustainable and pleasurable. Organisations, such as supermarkets and restaurants, pledge to follow these directives, in the hope of changing the way the country treats vegetables. Their website features ways in which individuals, communities and businesses can engage with the initiative and forge better relationships with vegetables. 

Read the article

Glossary

Photo by Artem Kostenko on Unsplash

Calcium comparisons between dairy, soy and almond beverages

Read the article

Research in the journal Current Developments in Nutrition has found that almond beverages were inferior to both milk and a calcium-fortified soy drink for bone health. 

The New Zealand researchers fed rats diets supplemented with either milk, or a soy-based or an almond-based drink. They analysed the amount of the liquid and feed consumed, as well as indicators of bone health and body composition. Fortified with calcium, the soy drink had the highest calcium (181 mg Ca/100 mL) and energy content (66 kcal/100 mL), while the almond drink had the lowest for both (105 mg Ca/100 mL; 29 kcal/100 mL). Milk lay in between for both energy and calcium (127 mg Ca/100 mL; 65 kcal/100 mL). 

The animals given the almond drink showed the least weight increase and the lowest body fat content. In terms of bone health, these animals showed the least bone growth, the lowest bone calcium content and the weakest bones. The fortified soy drink had results similar to those for milk, which is interesting given that the difference in calcium content between the almond drink and milk was far less than the difference between the fortified soy drink and milk. 

Many people, due to personal choice or health reasons, replace milk with plant-based beverages. The authors emphasised the need to consider more than just the energy or protein content of these replacements, which is particularly pertinent for elderly people prone to poor bone health. 

Read the article


Glossary

Photo by Mehrshad Rajabi on Unsplash

Saturated facts

For nearly 50 years it has been believed that saturated fat is linked to heart disease. However, the scientific evidence does not universally support this assertion and recommendations are being made to change dietary guidelines and public knowledge around saturated fat. 

In response to increasing rates of heart disease in Western populations in the mid-20th century, the results of epidemiological studies comparing diets in different countries suggested that saturated fat intake could be a risk factor. Minimising the intake of saturated fat-containing foods such as red meat, dairy and chocolate was advised as a result. Currently, the NZ and UK dietary guidelines recommend reducing saturated fat intake, while the US and Australian Dietary Guidelines recommend the restriction of saturated fatty acids (SFAs) to less than 10% of total calorie intake in order to reduce the risk of cardiovascular disease (CVD). 

Saturated fatty acids (SFA), colloquially termed saturated fat, are molecules found in many common foods, especially animal fats and certain plant oils. Saturated refers to the molecular structure of the fatty acids, which have only single bonds between the carbon atoms, which cannot bond with any more hydrogen: thus, saturated with hydrogen. 

The claim that saturated fats were linked to negative health outcomes was accepted by public health institutes such as the World Health Organisation and the American Heart Association, and quickly caught on as a widespread belief. This has become so ingrained that, despite evidence to the contrary, it is proving difficult to change nutritional guidelines and the opinions of medical professionals, nutritionists, and consumers.  

A recent study, published in the Journal of the American College of Cardiology (JACC), performed a meta-analysis of randomized trials and observational studies on saturated fat. It was found that there were no beneficial effects of reducing SFA intake on cardiovascular disease and total mortality. While it was found that SFAs do increase cholesterol in most individuals, they increase concentrations of large particles of low-density lipoprotein (LDL) cholesterol, which is less correlated with CVD risk than the small, dense particles.  

An important finding of this study was that health effects could not be predicted from the SFA nutrient group alone; consideration of the overall macronutrient distribution and food matrix was necessary. Different SFAs have different physiological effects, which are further influenced by the foods they are found in and the carbohydrate content of the diet. Several foods relatively rich in SFAs but also rich in other nutrients, such as whole-fat dairy, dark chocolate, and unprocessed meat, were not associated with increased CVD or diabetes risk. 

There are calls to examine the overall risks of foods containing SFA, rather than SFA themselves. Likewise, the replacement of SFA-containing foods with those containing other fatty acids, often recommended in nutritional guidelines, was found unlikely to reduce CVD events or mortality. The authors of this last publication warned that current recommendations to replace SFA with alternative fatty acids may hinder efforts to get people to adopt more beneficial lifestyle changes, thinking that this single dietary change may be sufficient to reduce their CVD risk. 

One of the studies included in the JACC meta-analysis was the PURE (Prospective Urban Rural Epidemiological) study of 135,000 people from 18 countries on five continents. It found all types of fat (saturated, mono-unsaturated and polyunsaturated) were not associated with CVD, and saturated fat had an inverse association with stroke. Additionally, fat intake was associated with lower risk of total mortality. In contrast, a diet high in carbohydrates was associated with higher overall mortality risk.  

The claims around the negative consequences of fat intake may themselves have caused health problems. Reduction of saturated fat in the diet can lead to excessive consumption of carbohydrates as a replacement. Prevalence of obesity and type 2 diabetes has exploded in recent years, as seen in the chart below. Dr James Muecke, 2020 Australian of the Year, wrote in the Canberra Times“A flawed dietary guideline, which we have obediently and blindly followed for 40 years, is literally killing us. We’ve been encouraged to eat less fat and consume more carbs and yet we’ve never been fatter, our teeth never more rotten, and type 2 diabetes and its complications never more prevalent.” Dr Mueke makes clear the far greater need to prioritise reductions in excess carbohydrate consumption, rather than reductions in fat, to reduce the rate of non-communicable diseases in developed nations like Australia.

Rapidly increasing prevalence of obesity globally over the last 40 years. Source: World Health Organisation

In addition, advice to reduce consumption of nutrient-rich foods such as dairy and meat risks limiting the intake of nutrients such as calcium, iron, zinc, riboflavin and Vitamin B12. The Global Burden of Disease study shows that in the main, global health problems are caused more by what people do not eat – either through poor choice or through lack of choice – rather than an excess of certain foods. With the exception of excess sodium, the highest association of mortality and disability-adjusted life years globally was with insufficient intake of nutrient-rich foods. The study also showed the problems of consuming excess sugars. Consuming calorie-rich but nutrient-poor foods (e.g., sugary drinks) can displace nutrient-rich foods in the diet. The Global Burden of Disease study demonstrates that diets low in nutrient-rich foods are correlated with higher mortality. Importantly, saturated fat intake did not appear with any link to higher burden of disease. 

Number of deaths per 100 000 population attributable to individual dietary risks at the global level in 2017. Reproduced from the Global Burden of Disease study.

It is important for policy makers and health institutes to take all evidence into account when- designing nutritional guidelines. Arbitrary recommended intake levels for saturated fat will be less useful for the prevention of CVD or reduced mortality than targeting excess consumption, particularly of carbohydrates, and micronutrient deficiencies. Foods containing saturated fat, such as meat and dairy, can contribute to a nutritious balanced diet. They certainly should not be removed from the diet due to their saturated fat content, which has inconsistent links to modest impacts on CVD. Replacing these foods with carbohydrates will likely cause greater damage. 


Glossary

Photo by Anna Onishchuk on Unsplash

SNI in spotlight at Primary Industries NZ summit

Representatives from industry, policy and research came together last week to attend presentations on trade, sustainability, consumer science and future trends for the primary sector in New Zealand at the Primary Industries Summit in Wellington. The summit, organised by Federated Farmers of New Zealand, was held at the Museum of New Zealand Te Papa Tongarewa (23rd – 24th November). Delegates heard a selection of world class, global and local experts delivering insights that will support and enable the sector to plan and prepare for its transition and adaptation to a sustainable future.

On the second day of the summit, over 400 delegates heard from the Riddet Institute’s Dr Nick Smith, who discussed the research being undertaken by the Institute’s Sustainable Nutrition Initiative (SNI). SNI focuses on how global food production will need to adapt to adequately and sustainably meet the nutritional requirements of the world’s population, now and in the future.

After the opening keynote from the Prime Minister, the Rt Hon Jacinda Ardern, Nick gave an overview of the global food system, which encompasses far more than our common perception of farm, processing, distribution and consumption. Professor Warren McNabb, deputy director of the Institute and leader of SNI, comments “our research investigates many aspects of the global food production system, including food waste, international trade, environmental impacts and governance. We incorporate this into a working model (the DELTA Model) to assess scenarios for delivering sustainable and adequate nutrition for all”.

Nick’s talk struck a chord with the audience as he discussed micronutrient availability (what is often called ‘hidden hunger’) and his contention that a global food production system that fails to nourish people can never be considered sustainable. Although macronutrient production is currently more abundant than many people think, our current global food production system paints a chilling picture when the supply of micronutrients is considered. For example, the world doesn’t produce enough calcium or Vitamin E for its current population, and these deficiencies will grow as the population increases. Other micronutrients, including those sourced predominantly from animal foods, like Vitamin B12, will likely be problematic in the future. Nick reiterated that any proposed changes to food production must consider the nutritional consequences to people, alongside environmental considerations, if our global food production system is to be truly sustainable.

Sustainable nutrition is a key research topic for the Institute, given our vision to support the primary industries with their adaptation to a sustainable future and underpinning their products with world class fundamental science. Nick outlined to the assembly SNI’s key findings in the area and also discussed the work of Distinguished Professor Paul Moughan. Paul and his team recently demonstrated that a US citizen could purchase a nutritionally adequate diet for US$1.98 a day (NZ$2.83). Nutritionally adequate means a diet that is able to supply all the nutrients needed by the consumer.  An adequate, but entirely plant-based diet would cost US$3.61 (NZ$5.15). This emphasised the role of nutrient dense animal-sourced foods in a nutritious and affordable diet.

The DELTA Model allows current and future global food production system scenarios to be analysed for their ability to supply sustainable and adequate nutrition to the world’s population. Our work with DELTA demonstrates that sufficient macronutrients (i.e. energy, protein, fat) are produced today to nourish the world’s population. In fact, from a macronutrient perspective, we already produce enough food to feed the forecast 2030 world population of 8.6 billion. The issues are really around the supply of the aforementioned micronutrients and trace elements. 


Glossary

Photo courtesy of PINZ2020

The requirement for balanced global diets that connect 9 billion consumers


Wayne Martindale, Associate Professor of Food Insights and Sustainability at the University of Lincoln, provides a perspective on sustainable diets and how we should think about them.

The food and beverage system functions globally; we all source our meals from a global marketplace. The responsibility for a nutritious and balanced diet begins with producers and manufacturers before it is presented to consumers. The flow of foods and ingredients in the global food system provides many surprises.  

This article is a viewpoint from Europe and the United Kingdom, where our nation is soon to realise the impact of globally sourcing our food. Sustainability and security are inseparable attributes here and we believe a sustainable diet must provide balanced nutrition and security. This article will develop this relationship using existing evidence and demonstrate that limiting the discussion to a single attribute of sustainability such as greenhouse gas emissions, biodiversity or land use change will only result in polarised debates that will never get us to where we need to be. 

Best practice in the food and beverage industry has been transformed by sustainability. It resonates across industry and consumers as an ideal we should rightly strive to achieve. Much of what we have been aiming for is to reduce the greenhouse gas emissions associated with the production and consumption of foods. Manufacturers are now reporting carbon zero product categories including whole milk and beef, which was unthinkable ten years ago. Our improved understanding of how resources flow through food systems has made carbon zero a reality. Programmes that sought to reduce greenhouse gas emissions ten years ago exposed many gaps in our understanding of food systems.  

The initial debates tended to demonise food and beverage products with higher carbon footprints – namely livestock products and beef (Cederberg et al., 2011). What these studies did not consider was nutritional delivery and consumer experience, both of which are important because without them sustainability will never be delivered (Haddad, 2018). This is because every meal must deliver balanced nutrition and a favourable experience. If it does these two things, it is more likely it will result in optimal health and not be wasted. I was working with CSIRO in Melbourne as a McMaster Fellow when I realised that these relationships were critical. This was in part due to the publication of the Total Well Being Diet (TWD) book by CSIRO (Noakes and Clifton, 2005). What influenced me here was the fact that a formalised and scientifically formulated diet for health – the TWD – could resonate so strongly with consumers that a Government Science Agency publication on dietary change became a best seller! In the UK, this was only achieved by our best celebrity chefs, with the science part often in second place for editorial decision making. The TWD demonstrated the requirement for a healthy diet is clearly resonant with consumers. The notion of what is a sustainable one was less so, but it raised the issue of whether the two are related in any way? 

The issue of sustainability in food has often been associated with carbon footprint. The first studies of crop and livestock production that calculated what we now recognise as a carbon footprint were reported over 20 years ago (Brentrup et al., 2000). These were transformative in that they identified production processes that could reduce greenhouse gas emissions. In the case of agricultural products, their application resulted in reductions in diesel and fertiliser nitrogen used in sustainable farming.  

However, in terms of guiding responsible consumption, carbon footprints can be cumbersome. Such direct measures of carbon footprints for food lead to comparing livestock and plant proteins without considering any dietary requirements. Consumers are often told to not eat specific products, with beef being the main target for such attacks. This leads to a ‘stand-off’ in the sustainability arena, stifling innovation in manufacturing. Nutrition, consumer experience and taste all play an important role in quantifying what is sustainable, and they need to be accounted for when we place carbon footprinting into diets, meals and lifestyles. 

Carbon zero thinking has been transformative in breaking this deadlock and the launch of branded zero carbon livestock products such as whole milk, beef and lamb have shown that food producers and manufacturers are confident in claiming it (read more here). The subsequent re-thinking of carbon footprinting is enlightening because it can be related to achievable and nutritious diets and lifestyles so that responsible consumption is possible.  

Plant products typically have a lower carbon footprint than livestock products. Converting plant protein into livestock protein as efficiently as possible often means an increased carbon footprint. But even here there are exceptions. For example, rice has a greater footprint than whole milk (Clune et al., 2017). This is because of the requirement to flood and drain the soils used to grow rice, resulting in methane emissions (Burney et al., 2010). 

Consideration of production volume can provide a transformative view of the global food system carbon footprint. Production of the ‘big four global commodity crops’: rice (0.7 billion tonnes per year), wheat (0.7 Bn t/yr), maize (1.0 Bn t/yr) and soy bean (0.3 Bn t/yr) account for around 2.8 billion tonnes of production each year (Clune et al., 2017). Three of these crops have a carbon footprint of 0.5 tonnes CO2-equivalent per tonne production, and rice has 2.6 tCO2-e/t, summing to 2.8 Billion tCO2-e associated with the big four each year. The mean or average carbon footprint for beef globally is around 25 tCO2-e/t, some 50 times that of wheat, maize and soybean crops, used for both feed and food. However, only 64 million tonnes of beef are produced globally each year, which accounts for some 1.5 Bn tCO2-e. The GHG ratio of the ‘big three’ (‘big four’ excluding rice) to beef is therefore not 50 but 1.5! If we include rice, beef has half the global carbon footprint of the big four crops. This means we are being mis-led by slavishly following carbon footprint data alone. 

There is also much more here, in that a number of studies on beef for the reported average carbon footprint include the prime production of Wagyu beef under extremely intensive conditions (beer and massages) that holds no resemblance to grass fed and finished beef systems including typical Wagyu systems. The issue of production volume together with variation in carbon footprint data is overlooked in simplistic carbon footprint assessments. If we include variation in livestock production systems, the idea of a typical carbon footprint becomes unrealistic at best! Moreover, the spotlighting effect of carbon footprint will often leave the issue of nutrition aside and this is another reason there is a requirement to look at how carbon footprints of food are measured.

If we were to eat the lowest carbon footprint food group per calorie it would be cake and confectionery alone, because these foods have a carbon footprint of around 80 gCO2-e/100 kcal, whereas fruit and vegetables produce over 400 gCO2-e/100 kcal (Drewnowski et al., 2014). This is surely the opposite to what we are told as consumers. Milk and dairy products are in the middle of this range, lower than meat. And this is only considering calories; considering other essential nutrients such as protein would likely paint a different picture again. The dietary context for carbon footprint clearly needs to be clarified and that is why the Sustainable Nutrition Initiative seeks to find methods of providing robust evidence that will guide realistic, sustainable consumption that provides good health. 

An improved ability to access data has brought energy balance and carbon footprinting into the consumer goods arena and the drive for carbon zero is creating much innovation in food and beverage. It has brought sustainability closer to the consumer in that the consumption of a nutritionally balanced diet can be delivered sustainably even if we do not choose or eat food based on carbon footprints.  

It is important that improvements do not get lost in purely carbon footprinting diets. We are developing models for the UK that identify where critical points and connectivity in the food system control resource flows (Martindale, Duong, et al., 2020). These can be integrated with the nutritional insights of the DELTA Model developed by the Sustainable Nutrition Initiative and build on established indices of food sustainability. New Product Development (NPD) is the operational activity we are focusing on because, if product developers and technologists build in sustainability at the concept stages, there is an increased possibility that the final product will deliver it (Jagtap and Duong, 2019). One of our models – Centreplate – is currently being tested with respect to NPD strategies, improving protein supply and reducing waste (Martindale, Swainson, et al., 2020).  

We are currently at a point where food system insights have the potential to bring sustainability and nutritional datasets together because of two technological advances we would consider most notable. The first is the ability to embed digital technologies into resource packaging so that traceability and analysis of supply chain data can be enabled securely for most food companies (Martindale et al., 2018). The other is the projection of dietary impact of nutrition on populations. This changed forever a generation ago in response to the newly sequenced human genome. What followed was a scramble for therapeutics but the interaction of health and nutrition through our diet was largely overlooked (King et al., 2017). We now have a greater understanding of how genes and metabolism interact with what we choose to eat. It is essential to keep the food system lens, and this is what the Sustainable Nutrition Initiative’s DELTA Model does. Connecting datasets and making sure we speak to each other is becoming increasingly important. This is otherwise known as interoperability in the digital arenas. We have the capability to deliver a net zero sustainable food system, but without interoperability it will not happen. 

Our food future depends on all partners in the global system connecting methods and data that will guide sustainable dietary choices. At present the sustainable diet arena is noisy and confusing for many consumers because polarised views can dominate. This is why actions such as the Sustainable Nutrition Initiative are so important; they lay bare facts and guide routes to sustainable and secure global consumption that still provide the choice and experience that consumers require.

Wayne Martindale directs the Food Insights and Sustainability Service at the National Centre for Food Manufacturing at the University of Lincoln. Wayne has been working in sustainability since 1998, after eight years of doctoral research in biochemistry in the UK, Japan and USA. He started his sustainability practice with the BASIS/FACTS leadership team delivering certification programmes for UK agriculture and has held visiting scientist roles at CSIRO Australia and the OECD in Paris.


Glossary

Photo courtesy of Wayne Martindale.

Links found between maternal vegetarianism and infant stunting

Read the article

A study in the Journal of Nutrition has found that maternal and household diet were significantly correlated with the risk of child stunting, wasting and anaemia in India.

India has high rates of infant stunting (38%) and anaemia (58%). Around a quarter of Indian households are vegetarian. The study used the 2015-2016 National Family Health Survey (NFHS) and 2011-2012 National Sample Survey (NSS) to explore correlations between parental vegetarian and vegan status and child stunting. 

Children with vegan mothers were moderately but significantly more likely to be stunted, wasted or anaemic when compared with non-vegetarian households. Contrastingly, children of lacto-vegetarian mothers, who consume dairy more frequently, were less likely to be stunted compared with children of non-vegetarian mothers. 

Animal-sourced foods are rich in calories, high-quality protein, and a range of critical micronutrients. The authors state that exposure to a strictly vegetarian diet in early childhood or in utero could be a significant risk factor for malnutrition in India. More frequent dairy consumption in lacto-vegetarian households might help to explain the reduced risk of stunting in these households. Dairy has high concentrations of vitamins and minerals and has a rich amino acid profile including lysine, which is often limiting in traditional Indian diets.   

This study does have its limitations. For example, it does not provide in-depth exploration of associations between vegetarianism and religion or caste, geography or wealth. However, it does emphasise the importance of dairy and other animal-sourced foods, as well as dietary diversity, for healthy childhood development in India.

Read the article


Glossary

Photo by Nischal Masand on Unsplash