Antinährstoffe: positive und negative Eigenschaften, Vorkommen und Verminderung

April 6, 2020 Zarina Birnbacher

Antinutrients: positive and negative properties, occurrence and reduction

Phytic acid

In the plant world, phytic acid binds phosphorus and other minerals such as calcium , iron, zinc, magnesium, and, in small amounts, the trace elements copper and manganese . Heavy metals, for example, are among the long list of minerals that can be bound by phytic acid , which is certainly a positive effect.

In turn, the enzymes for protein digestion can be blocked by phytic acid.

Phytates have other beneficial properties

Studies suggest that its antioxidant effect may protect against cancer, particularly colon cancer. ¹
Blood sugar regulation through delayed absorption of starch
can protect against iron excess

Occurrence (in descending order)

Wheat, barley and rye bran
Nuts (especially peanuts)
seeds
soy
Wheat and grain products
Legumes

Reduce
Cooking doesn't do much harm to this substance. It's best to reduce phytates by eating soaked and sprouted grains, nuts, and beans. The germination process produces the enzyme " phytase " in the grain. This breaks down the phytic acid, releasing the stored phosphorus, which serves as an energy source for the sprout. Another helpful step is fermentation.

oxalic acid

Oxalic acid consumes calcium, iron, and magnesium and inhibits protein absorption. ²

Oxalates are found in almost all plants (listed in descending order)

Amaranth
Black tea
peppermint
spinach
Star fruits
Cocoa, chocolate
Rhubarb, raw
Rhubarb, cooked
Wheat bran
chard
sorrel
Nuts
Beetroot
soy
potatoes

Reduce
It is recommended to reduce oxalates by cooking the vegetables, making sure that they are prepared in the healthiest and most gentle way possible.
The cooking water contains dissolved oxalates and is not intended for further use.

Drinking a lot stimulates kidney function and is useful because it can prevent the deposition of oxalic acid and thus the formation of kidney stones (oxalate stones).

The season also influences the oxalic acid content, which tends to be lowest in young plants in spring.

If you have iron deficiency, you should avoid espresso or black tea with meals and wait at least two hours before drinking it.

Lectins

Lectins are sticky protein molecules that bind to specific carbohydrate structures and are therefore able to attach to cells and coat the digestive tract, making it difficult to digest and absorb all nutrients.

(For example, tablets designed to prevent carbohydrate absorption are made from bean lectin.)

Lectins, like antibiotics, can damage the intestinal mucosa and alter the intestinal bacterial flora.

Lectins are also often referred to in cases of " leaky gut syndrome. " With a permeable gut wall, lectins can enter our bloodstream and, due to their similarity to proteins, confuse our immune system. This can lead to autoimmune diseases.

Lectins can cause red blood cells to clump together and, as a result, blockages in veins and arteries .

They disrupt cell communication and thus, for example, disrupt the hormonal system.

Because lectins are toxic to microorganisms, they are often used as pesticides.

Happen

Legumes
Wheat
Grains Spelt Rye Barley
rice
soy
Beans
Nuts and seeds
corn
potatoes
tomatoes
Eggplants
paprika
pepperoni
Cucumber, zucchini, melon, pumpkin

Reduce
It is advisable to reduce lectin intake by soaking, sprouting, fermenting, and cooking high-lectin foods such as grains, nuts, seeds, and beans.

Trypsin inhibitors

The enzyme trypsin is partly responsible for protein digestion. Trypsin inhibitors (TI) inhibit precisely this process.

Crohn's disease or rheumatism can worsen because TI activates the intestinal immune system and thus triggers inflammation. ⁴

Trypsin inhibitors have also been introduced into various plants at the molecular level to reduce the growth and survival of pests. ⁴

Happen

Cereals (mainly gluten-containing)

Wheat
barley
rye
Kamut, spelt
Emmer

Medium

soy
buckwheat
millet
Tef
Einkorn

Low

lenses
Quinoa
Oats

reduction
It is best to cook foods rich in trypsin.

Saponins ^{(Latin sapo “soap”)}

Saponins taste bitter and cause foaming in water.
This factor makes them an ideal additive in the food industry as foaming agents, for example in beer or soft drinks.

Saponins are secondary plant substances and also have beneficial properties . For example:

They can have an antibiotic effect (inhibit the growth of microorganisms such as bacteria and fungi)
They stimulate the immune system
They bind cholesterol
They have an anti-inflammatory effect

However, saponins must not enter the bloodstream because they trigger an immune response.* Even small amounts of saponins in the bloodstream lead to the destruction of red blood cells. ⁵

*(Reaction of the immune system to organisms or substances that it has recognized as foreign)

Saponins are found in vegetable plants such as

Soybeans
Peanuts
Legumes
spinach
Oats
Eggplants
asparagus
fennel
Garlic
Beetroot
sugar beets
tomatoes
green beans
green peppers
potatoes
onions
tea
ginseng
Jiaogulan
chestnut

Reduce
When legumes are soaked, approximately 10% of the saponins are transferred into the water.
Some saponins are destroyed by up to 50% during cooking, others (e.g. from soybeans) are heat-stable and should be additionally fermented.

Isoflavones ⁶

Isoflavones are also known as phytoestrogens. They are hormone-active substances (endocrine disruptors) derived from plants. They also exert an estrogen-like effect in humans, which is why they are primarily used to treat menopausal symptoms in women. Unlike synthetic drugs, this therapy poses virtually no cancer risk.

Positive effect on

Menopausal symptoms [Kostelac et al., 2003]
Counteracting osteoporosis in postmenopausal women [Kalaiselvan et al., 2010].
Lowering bad cholesterol, increasing good cholesterol
antiatherosclerotic, antioxidant and cardioprotective effects
Reducing the risk of developing hormone-dependent cancers (breast or prostate cancer)*[Wolters and Hahn, 2004]

*Protection against breast cancer only appears to occur if the isoflavone-rich soy foods were consumed before puberty.

Which foods contain isoflavones?
Soy and red clover are the main sources. Small amounts are also found in animal products, as some livestock feed contains soy or red clover.

Avoidance
Soaking and cooking can reduce isovlavones.