Nutrient decline in fruits and vegetables

The nutritional content of vegetables and fruits decreases

The nutritional content of vegetables and fruits has declined significantly in the last 50 to 100 years. This is proven by several studies.

The dilution effect

In 1981, Jarrell and Beverly demonstrated the so-called dilution effect for the first time: they have shown that yields have increased enormously since the 1940s through the use of fertilizers and other measures, while the concentration of minerals and nutrients in plants has fallen. This is the first evidence of a negative correlation between yield and nutrient content in different vegetables, cereals and fruits.

How does the dilution effect come about?
The plants collect more mass, so provide more yield. The amount of nutrients it contains remains the same. The result: 100 grams of high yielding plants contain less nutrients than 100 grams of lower yielding plants.

Further studies confirm this dilution effect: A study by Davis et al. examined the decline of proteins and vitamins in 43 vegetables and fruits in 2004 and showed an average decrease of 6% in proteins and 15-38% in vitamins.

Ekholm et al. In 2007, Finland also showed a decline in nutrients in various plants since the mid-1970s. 17 vegetables, 6 berries, 4 cereals and apples were examined. Decreases of vitamin K, magnesium, zinc, copper, calcium, manganese, iron and phosphorus were confirmed.

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 2002 and Scott 2006.

In the course of these studies, traditional low-yielding vegetables and crops were planted under the same growing conditions alongside new high-yielding varieties. Thus, the soil condition, cultivation and climatic conditions could be excluded as influencing factors on the dilution effect. The only difference was the genetic characteristics of the seed.

Nevertheless, all four studies showed a negative correlation between yield and mineral concentration. The new, higher-yielding plants contained fewer nutrients than the old, lower-yielding ones.

This is sometimes because more plants had to divide up the same amount of nutrients from the soil. And the lower plant density brought less yield, but the plants could provide more nutrients.

While in the past, the dilution effect was always attributed to external conditions such as fertilization, soil conditions and climate, these studies showed that the dilution effect is due not only to external influences but also to the genes of the seed.

Yield increases and modern farming methods

During the Green Revolution in the 1960s and 1970s, yields doubled and tripled in the main growing areas, especially vegetables.

These increases in yield in connection with modern cultivation methods thus lead to a steadily decreasing nutrient concentration in vegetables and fruits. This is due to both the genetic and the environmental dilution effect. On the one hand, the lower nutrient concentration is already in the genes of today's seed, on the other hand, the nutrients contained in it are further reduced by fertilization and modern cultivation methods.

Welch and Graham showed in a study in 2004 that more than three billion people worldwide suffer from a lack of nutrients and vitamins. Fruits and vegetables are the main sources of this, so a decline in healthy ingredients in these product groups is very problematic and momentous.

Medical observation - consequence for Sanopoly

In various practices, the vital substance status has been collected over a long period of time, symptoms recorded and the proportion of deficiency responsible for certain symptoms determined. So a picture of what was missing resulted.

Sanopoly's approach was to prevent and treat these vital deficiencies that can be symptomatic. This is how dietary supplements and dietetic foods are made that are tangible, measurable, and completely balancing these nails and acting preventative.

Assembling data and publications for a quick overview, click here for a PDF download.


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