“Most of us don’t think about soil when we sit down for a meal with friends and family. But we should. We all know that a fresh pear is healthier than a pile of salty potato chips, but it’s all to easy to lose sight of another dimension of our health: what’s in that pear and how it got there – how we grow our food.” – Anne Biklé and David Montgomery (What Your Food Ate)

Nutrient density is a hot and important topic. It’s traditionally defined “the concentration of nutrients (such as vitamins, minerals, proteins, fatty acids, carbohydrates) in a given portion of food”. It measures the ratio of beneficial nutrients to the total number of calories.

Nutrient density exists as a continuum, a sliding scale from very high to very low. Nutrient dense foods are the opposite end of the spectrum to foods referred to as “empty” (which is most ultra processed foods). It’s important to bear in mind that nutrients are not inherent characteristics of food, they accumulate.

Why is the traditional definition in need of an update?

Because there are varying opinions and definitions on what actually constitutes a ‘nutrient’. Are nutrients only substances essential for growth, development and maintenance of the body (i.e. fats, proteins, carbohydrates, minerals and vitamins)? Or can the definition of ‘nutrients’ be expanded to recognise secondary metabolites (such as flavonoids and phenolic compounds produced by a plant), which can enhance human health through providing antioxidant properties, supporting immune function, reducing inflammation and support microbiome health?

I strongly believe these metabolites (also called phytochemicals) should be included in the conversation when talking about the nutrient density of food. After all, a food’s nutritional profile extends far beyond the dozen or so nutrients listed on a nutrient panel. There have been roughly 50 000 different phytochemicals that have been identified so far, which represents only about a third of what’s predicted to be discovered over the coming years.

As John Kempf once said regarding secondary metabolites, “If we are to have a legitimate conversation about food as medicine, THIS is where the medicine lies”. 

Can nutrient density, including phytochemical levels, be measured?

There has been (and still is) great difficulty testing the full spectrum of nutrients – referred to as the ‘food matrix’. Researchers have only just begun to test the hundreds to thousands bioactive compounds that are present in wholefoods (using mass spectrometry and metabolomics). There are companies, such as the Bionutrient Food Association, who are creating a hand-held device which gives a spectral signature on nutrient density. They’re working on making this accessible to the public, but are still in the research and development phase.

Until we get widespread and affordable access to such devices, how do we determine if a food is truly nutrient dense? 

Here are four indicators:

• Flavour – Flavour is achieved through sufficient minerals and an abundance of phytochemicals (deliciousness = nourishment!)
• Colour – Food imparts colour, a frequency of visible light and a functional signature found in nature through phytochemicals
• Freshness – The closer most produce is consumed post-harvest, the better in regards to nutrient density
• Longevity – Produce with high nutritional integrity lasts longer compared to nutrient poor produce. 

As an example, the strawberries we grow ourselves are packed FULL of flavour, they are incredibly bright in colour and they last a lot longer after picking compared to store-brought strawberries. Nutrient dense food is also more satiating and difficult to overeat. I can’t imagine being able to overeat liver, egg yolks, 90% dark chocolate, sauerkraut or bitter greens – why? They are incredibly nutrient dense!

And finally, KNOW THY FARMER. What farming practices do they use? Are they regenerating their soil? When did they harvest the produce they’re selling? Are they transparent and open in how they are producing the food they sell? If they start chewing your ear off about soil, worms, animal health and compost… you’ve probably found a winner!

If you live rurally or remotely and have limited access to fresh foods, choosing organic produce when it’s available to you and/ or seasonal produce can help with the overall nutrient density of your diet (and if you’d like a copy of my long life nutrient dense food chart, please let me know!)