WHAT SHOULD I EAT? - PLANTS GROWN IN GOOD SOIL. part 2

This is the second article in the series discussing the nuances of food as both a base physiological need, and a source of nourishment which you may want and be able to improve. In the last article, we described that most people are the most nourished when they eat mostly fresh plants and some fungi. There are specific reasons why some folks may do better on a different type of diet (like keto diets for people with cancer or brain conditions), but for the vast majority of people, plant-based is best.

plants are what they eat

We are what we eat, and so are plants. Plants absorb carbon from carbon dioxide in the air through pores in their leaves called stomata. Plants receive all their other nutrients from the soil: both directly through their own root system and through mycorrhizal networks with fungi. (Here’s another plug for the documentary Fantastic Fungi)

There are primary nutrients: oxygen, hydrogen, nitrogen, phosphorus and potassium, which are needed in the greatest quantity. There are also secondary nutrients: calcium, magnesium, sulfur, which are needed in lesser quantities. Then there are micronutrients needed in small quantities as the name suggests: chlorine, iron, zinc, manganese, boron, copper, molybdenum. More on this here.

These nutrients are derived from the breakdown of organic matter by microbes. A diversity of soil microbes is needed, with a whole ecosystem of insects, worms, bacteria, protozoa and fungi (collectively called soil biota). Intensive agriculture leads to a depletion of soil nutrients through a reduction in organic matter availability and soil biota. Especially if only one type of plant or crop is grown in an area (monoculture or monocropping) then certain nutrients specific to that plant will become more rapidly depleted. To address this, farmers add a range of different fertilisers and amendments to the soil. And what about the organisms that break down matter to get nutrients into the form that plants can take up? The use of herbicides and pesticides drastically reduces the diversity of soil biota, and therefore the nutrient content. Many of these -cides are being absorbed into the plant and then by us as we eat them. I am sure you have heard about the herbicide glyphosate (Roundup) and issues with human consumption, especially concerns it can cause cancer. You can search the credible journal database PubMed e.g., “glyphosate AND health” to read more.

Organic farming does not use these chemicals.

soil depletion

The soils that our food and plant medicines are commercially grown in are frequently deficient in one or more nutrients, so our food will also be deficient. With the intensity of commercial agriculture, monocropping, soil erosion from wind and water, and use of herbicides and pesticides, there has been a worldwide depletion of topsoil. Topsoil is the top 13-25cm of soil which contains most of the soil biota and nutrients and organic matter. Without quality topsoil, our food becomes seriously depleted. We can eat as “healthy” as we want, but if we are not eating organic plants grown in good topsoil, we are not fully nourished.

Phosphorus, carbon and nitrogen are the plant nutrients most important for plant growth. Obviously farmers/big ag will make sure there are enough of those nutrients otherwise the plants won’t grow. Some of the other nutrients may not be so carefully controlled. Magnesium, in particular, is a nutrient (mineral) which is seriously depleted in the soil and in the plants we eat. It is estimated that our fruit and vegetables have lost 80-90% of the magnesium content in the last 100 years. Not only is there less magnesium in the soil, but adding a lot of phosphorus (fertiliser) can bind the magnesium and prevent uptake by plants. Acidic soils and acid rain also reduce availability of magnesium. Processing of foods and even cooking food will decrease magnesium. High fluoride levels in drinking water will bind magnesium. Caffeine and soft drinks (soda, pop) also reduce it. Some drugs will prevent the absorption or increase the loss of magnesium. More on that here.

magnesium deficiency is due to depleted soils

It is estimated that around half of Americans are magnesium-deficient. The recommended dietary intake (RDI) for adults is 320-420mg/day. There are some problems with the routine testing of magnesium- the blood levels do not necessarily correlate to the amount of magnesium available in the body.

So what are the signs of magnesium deficiency? Magnesium is a necessary component of many enzymes in the body which are involved in reactions for growth, healing, repair and maintenance. The symptoms of magnesium deficiency can include muscle cramps especially in the legs, general tiredness and fatigue, which are all common and pretty nonspecific signs. And expected symptoms of our capitalist way of life, let’s be honest. Severe magnesium deficiency signs are unlikely to be seen in people unless they are taking specific drugs or have specific conditions e.g., kidney disease.

(Special shout-out to my fellow veterinarians who treat cows with grass tetany – a severe form of magnesium deficiency.)

Leafy green vegetables, nuts, and whole grains are some of the best sources of magnesium. Even for people who have a nourishing diet, magnesium supplements may be helpful since the soils and therefore our food is depleted. This could be in the form of capsules or tablets, liquids, or even sprays (especially sprayed on the feet), and Epsom salt baths (Epsom salts are pure magnesium sulfate and will get absorbed across the skin). Supplementation is a whole ‘nother topic, but specifically on magnesium, I recommend getting the forms your body can actually absorb (organic-bound) e.g., magnesium gluconate, magnesium taurinate, magnesium citrate, magnesium glycinate. Magnesium oxide will not be well absorbed by the body so is best avoided, but is often quite cheap so is better than nothing. Magnesium sulfate can have a laxative effect so just be aware of that! Magnesium supplements are best taken about 30 minutes before bed, on an empty stomach, to maximise absorption and assist sleep. Puori is the brand I usually take and trust. It has 300mg of magnesium per serving (in gluconate and taurinate forms; 70% of the recommended daily intake), plus zinc, vitamin B6 and malic acid.

I have just started trying this Vital Proteins supplement which has 100mg magnesium in the citrate form (24% recommended dietary intake), plus the adaptogen ashwagandha, and L-theanine, and GABA.

If you take a multivitamin, take a look and see how much magnesium is in each serving, and which form it is in. More on magnesium here.

what can i do to help the soil?

The issue of topsoil quality is obviously an issue for agriculture, but unless we consumers apply pressure, we will keep getting sold that beautiful-looking corn which is lacking in nutrients. Topsoil depletion is also a serious environmental issue in terms of carbon emissions- a lot of carbon is stored in the soil.

Agricultural practices to improve topsoil health include crop rotation, cover crops, co-planting with trees or other plants for several reasons including to minimise erosion, and avoiding tilling the soil. More on this here.

We can’t know the difference between a nutrient-depleted vegetable and a less depleted vegetable just by looking at it. As a consumer, you can use your dollar to support regenerative farming practices. The absolute best thing is to grow as much of your own food as you can, organically. Compost! Worm farms! The next best option is to buy organic produce from local farms via a farm box, CSA (community-supported agriculture), or local farm stand. If that is not available, buying produce from your grocery store which is organic and as local to you as possible is the next best step. Otherwise, buying whatever fresh or frozen fruit, vegetables and herbs that are accessible to you is still better than buying packaged and processed foods.