When I worked in Thailand at the start of the century, I was told that local farmers divided their land into two sections.
The first section was where they grew crops for sale.
These were grown in the modern way, using pesticides and fertilizers.
The second was a smaller patch, where they grew their own food – without any modern pesticides or artificial fertilizers.
Later, when I worked in Indonesia, I found many city people would go to great lengths to buy eggs from “Ayam Kampung” (village chickens), rather than the factory-produced eggs at supermarkets.
Like Thai farmers and Indonesian city folk, a few scientists have suspected a link between how food is produced and our health for decades.
Indeed, writing in the 1940’s, Sir Albert Howard feared that the advances mankind was making in the field of health would be overdone by the damage we were doing to our soil.
He called for us to invest in that soil, stating:
Still, when you scan through studies on agriculture, the focus is generally on improving crops, not on the link between those crops and health.
In fact, when I’ve interviewed one expert before, and got to the subject of compost improving nutrition, he side-stepped the question with a “well, maybe.”
Fortunately, some studies are now starting to indicate that using compost for growing could be better for our health.
Green waste compost increases nutrient density
One five-year agricultural research trial conducted in Brandon, Manitoba, found that using compost made from food scraps and garden trimmings in food-growing soils produced higher yields with better nutritional values.
Conducted by Lord Abbey, PhD, of Dalhousie University’s Faculty of Agriculture, and supported by Manitoba Conservation & Climate and the Compost Council of Canada, the study grew four different vegetable crops, including lettuce, beets, carrots, and green beans.
The research concluded that:
Amino Acids in the compost-grown vegetables increased by between 18% and 323% compared to the control, while organic acids increased by up to 35%.
You can see the full study details at Biocycle.net.
Increased levels of anti-oxidants in carrots
A second study examined the impact of compost made at high temperatures on the growth of carrots.
The compost contained the bacteria Bacillus, which is a common bacteria found in hot compost heaps.
The study found that exposure to the compost led to increased levels of:
- amino acids
- flavonoids and/or carotenoids.
The carrots were also bigger and had a richer hue in colour.
Sir Albert Howard’s case studies
Sir Albert Howard, often regarded as the father of organic farming, was convinced about the link between good soil and human health.
In the 1940’s, he found a number of promising case studies that looked at the impact of compost-grown veg.*
For example, the Chief Health Officer in Singapore, Dr J W Scharff allocated land – and large amounts of compost – to labourers in Singapore.
By the end of the first year, he noted:
The benefits applied to the worker’s families, too, which suggests they came from the food, and not from the extra exercise involved in gardening.
Similar results were found across different countries and in different situations, from schools to factory workers and from New Zealand to Africa.
These case studies are old, and I haven’t been able to find any other similar collection of experiments conducted since then.
However, they make both fascinating reading and additional evidence for the benefits of growing vegetables in healthy soil.
Time to get composting?
It’s important to note that the one of the two studies focused on a specific type of compost – that made at high temperatures.
It’s possible that the results may differ from those commonly used in home gardens.
Still, despite the need for further research, the potential benefits of compost-grown vegetables are exciting – especially as more gardeners and farmers shift towards reducing fertilizer and increasing compost usage.
Instinctively, it makes sense.
We know compost improves soil health, and that food grown in healthy soil – or indeed animals that are raised on healthy soil – should be better for us.
Instinct is not a replacement for research. However, what research does exist is pointing in the right direction.
So if you’re keen to maintain or improve your health, it makes sense to make compost and experience both the joy of growing your own food and the likely health benefits of nutrition-laden vegetables from your compost-enriched soil.
Ready to try composting at home? Follow our step-by-step Home Composting Guide to get started today.
* See Sir Albert Howard writing in The Soil and Health, A Study of Organic Agriculture (1947). The case studies can be found in Chapter X: Soil Fertility and Human Health.