Growing Food for Nutrition

By Matt Adams for Organic Farming Magazine

Imagine a future where your food's nutritional profile was available at your fingertips. Not via a simplified, back-of-pack label, but a real-time snapshot of the nutrient density within the vegetable in your hands. It's a future where our understanding of what is in our food can tell us how well it's been grown.

Most of the food that is grown and eaten today is linked to the abundance of wealth not health. In the last 70 years, food production has measured success by external factors such as yield and appearance. In this same period, soil fertility has reduced (Arsenault, 2014), food has lost its nutrients (Mayer, 1997) and the prevalence of diet-related, non-communicable diseases continue to rise (Branca et al, 2019).

These trends are associated with a reductionist approach that attempts to dominate nature and, therefore, does not recognise the links between soil, food and healthy ecosystems.

The production of food has become fixated on either adding synthetic chemicals or not using them at all, with no consideration for the biological life in the soil and its function in producing highly nutritious food for human gut flora to thrive. Such an approach fails to pay attention to health - from soil to gut.

At Growing Real Food for Nutrition (Grffn) we are asking: "What makes a healthy plant grow so that it provides health for humans and the planet?" The beneficial microbes surrounding the roots of a plant and those living in human guts are very important for health. Measuring food for nutrient density could indicate the health of the plant and soil, and show whether the microbial ecosystem surrounding a food plant is broken or harmonious. Hence, what effect would nutrient dense food have on the microbial ecosystems in the guts of animals and humans?

Higher levels of sugar (in the form of carbohydrate) in a plant indicates that the plant has been grown in a minerally balanced, healthy soil ecosystem. The microbial life in the soil feeds on the sugary exudates released by the plant roots. In turn, the population of microbes in a well-fed soil ecosystem will increase in number because more food is available. Bacteria and fungi etc are the experts in sourcing mineral elements and making them biologically available for the plant (and us!) to build a healthy immune system. The strength of the bond that's created by the ecosystem surrounding just one plant can prevent pest and disease from entering the root zone. With access to sufficient mineral and trace mineral elements, plants can produce chemical defence mechanisms to repel pest attacks above ground. By growing more nutritious food, humans can re-enter these cooperative processes, which Lynn Margulis argued were the cornerstones to evolutionary development (Feldman, 2018).

Humans need to start thinking about their relationship with food systems in a more symbiotic way and measuring nutrient density could help. Defining food quality by its potential to deliver health for both people and planet requires humans to work closely with soil and plants to optimise living processes that are nourishing. By choosing to think differently and collaborate with nature, rather than compete with it, humans can become an integral part of a healthy ecosystem where everyone and everything benefits.

Measuring nutrient density

Dr Carey Reams, an early pioneer of the nutrient density concept, associates high sugar content (carbohydrate) with nutrient dense food. Sugar content is measured by squeezing a few drops of juice from a plant onto the lens of a hand-held refractometer, which indicates the amount of sugar using the Brix scale. In the 1970s he created a table of Brix values that categorised food plants into poor, average, good and excellent. Grffn used this method to test a variety of fresh vegetable samples during September and October 2019. Samples taken from different growers, using a variety of practices across different counties and soils, showed that carrots fell into the average category with only one categorised as good. Kale and cherry tomatoes ranged from poor to average, with a few good ones, whereas lettuce and spinach were all poor. It was also noted that the taste of good samples stood out from other samples and the aftertaste lingered to excite the senses!

Through field observation, high Brix values correlate to stronger resistance to pests and diseases, excellent yields, more flavour and higher levels of biological activity in the soil - all the elements associated with good nutrition - although this is yet to be rigorously tested. Hence, the need to develop the bionutrient scanner.

The Real Food Campaign

The Real Food Campaign, initiated by the Bionutrient Food Association in the USA, is developing an affordable hand-held scanner to replace the refractometer and enable measurements of nutrient density to be made in real-time. The scanner uses spectroscopy - light reflectance - to determine the composition of materials, such as their nutrient density. To calibrate such a tool involves collecting thousands of fresh samples along with the soils in which they were grown. Each sample is then tested for minerals, proteins, antioxidants and polyphenols along with soil sample tests (including microbes and carbon), so that results can be matched to the scanner results. When enough samples are collected, the open-source database will:
-> Expose the variation that currently exists in nutritional quality
-> Show the relationship between nutrient-dense food, soil microbial life and sequestration of carbon in the soil
-> Enable growers and citizens to use an affordable, user-friendly model of the scanner.

Will you join us?

Growing Real Food for Nutrition (Grffn), developed by Matthew Adams and Elizabeth Westaway, promotes the concept of growing nutrient-dense food. Grffn plans to conduct two citizen science research projects, the first being to benchmark nutrient density in the UK using Brix. The second is a partnership project linked to the Real Food Campaign in the USA to help develop and calibrate the bionutrient meter. This will expose nutrient values of fruits and vegetables in the UK in relation to soil health and management practices.

If you would like to be part of this symbiotic relationship, please register your interest at or email

Matthew Adams is a deep ecologist and environmental manager. His work focuses on developing projects for education and research around growing food for nutrition. He can be contacted on

Arsenault, C. (2014) Only 60 Years Left of Farming If Soil Degradation Continues, Scientific American. https://bit. ly/2XgmvUF
Branca, F. et al (2019) Transforming the food system to fight non-communicable diseases, BMJ, 364,1296.
Feldman, J. (2018) Symbiotic Earth: How Lynn Margulis Rocked the Boat and Started a Scientific Revolution. Oley, PA: Bulldog Films.
Mayer, A-M. (1997) Historical changes in the mineral content of fruits and vegetables, British Food Journal, 99(6): 207-211:

Published in: 
Organic Farming, a publication of the Soil Association
Matt Adams
Winter 2020