Nutrient decline in fruits and vegetables
The nutrient content of vegetables and fruits is decreasing
The nutrient content of vegetables and fruits has declined significantly over the past 50 to 100 years. Several studies provide evidence of this.
The dilution effect
In 1981, Jarrell and Beverly first demonstrated the so-called dilution effect: they showed that since the 1940s, yields have increased enormously through the use of fertilizers and other measures, but the concentration of minerals and nutrients in plants has decreased. In doing so, they were the first to document a negative relationship between yield and nutrient content in various vegetable, grain, and fruit varieties.
How does the dilution effect come about?
Plants accumulate more mass, thus providing higher yields. However, the amount of nutrients they contain remains the same. The result: 100 grams of high-yield plants contain fewer nutrients than 100 grams of plants with lower yields.
Further studies confirm this dilution effect: A study by Davis et al. examined the decline of proteins and vitamins in 43 vegetable and fruit varieties in 2004 and documented a decline of approximately 6% in proteins and 15-38% in vitamins.
Ekholm et al. also demonstrated in 2007 in Finland a decline in nutrients in various plants since the mid-1970s. The study examined 17 vegetable varieties, 6 types of berries, 4 grain varieties, and apples. Declines in vitamin K, magnesium, zinc, copper, calcium, manganese, iron, and phosphorus could be documented.
The genetic dilution effect
Shortly after the turn of the millennium, four scientists independently demonstrated the so-called genetic dilution effect: Farnham 2000, Garvin 2002, Monasterio & Graham also in 2002, and Scott 2006.
In the course of these studies, traditional vegetable and grain varieties with low yields were planted alongside new varieties with high yields under the same growing conditions. This made it possible to exclude soil composition, cultivation conditions, and climate conditions as factors influencing the dilution effect. The only difference was the genetic characteristics of the seed.
Nevertheless, all four studies showed a negative relationship between yield and mineral concentration. The new higher-yielding plants contained fewer nutrients than the old lower-yielding ones.
This is partly because more plants had to share the same amount of nutrients from the soil. And the lower plant density, although it brought less yield, allowed the plants to supply themselves more extensively with nutrients.
While previously the dilution effect was always attributed to external conditions such as fertilization, soil composition, and climate, these studies showed that the dilution effect, in addition to external influences, can also be attributed to the genes of the seed.
Yield increases and modern cultivation methods
During the green revolution in the 60s and 70s, yields doubled and tripled in the most important growing areas, particularly for vegetables.
These yield increases in connection with modern cultivation methods therefore lead to a steadily decreasing nutrient concentration in vegetables and fruits. Both the genetic and the environmentally-induced dilution effect are responsible for this. On the one hand, the lower nutrient concentration is already in the genes of today's seed, on the other hand, the nutrients contained are further reduced through fertilization and modern cultivation methods.
Welch and Graham showed in 2004 in a study that over three billion people worldwide suffer from a deficiency of nutrients and vitamins. Fruits and vegetables are the most important sources for this, so a decline in healthy ingredients in these product groups is very problematic and consequential.
Medical observation – Consequence for Sanopoly
In various practices, the vital nutrient status was recorded over a long period, symptoms were documented and the proportion of deficiency responsible for certain symptoms was determined. This resulted in a picture of what was missing.
Sanopoly's approach was to preventively address and remedy these vital nutrient deficiencies, which can be symptomatic. This created nutritional supplements and dietary foods that are able to noticeably, measurably and completely compensate for these deficiencies and act preventively.
Supporting data and publications for a quick overview, click here for a PDF download.
Sources:
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