Secondary plant compounds
Secondary plant compounds such as resveratrol, quercetin, or berberine have many health-promoting properties.
Secondary plant substances: nature as the best pharmacy
Plants protect themselves with certain substances against environmental influences such as pests or ultraviolet radiation. These bioactive molecules are known for their diverse health-promoting properties in humans and are commonly referred to as secondary plant substances .
Are there also primary plant substances? Yes, these include carbohydrates, proteins, and fats – in contrast to secondary plant substances, they are directly involved in the metabolic activity or growth of the plants. Secondary plant substances, on the other hand, fulfill the protective functions mentioned above. The more "wild" plants have grown, the higher the concentration of secondary plant substances.
You are what you eat – or is it not so?
Plants signal to us with their vibrant colors their numerous healthy ingredients. The shimmering blue of blueberries, caused by anthocyanins, a subgroup of flavonoids, promises strong antioxidant effects. Other flavonoids can be found in the crunchy skin of apples, or in the colorful varieties of bell peppers. Red grapes contain the ingredient resveratrol and in the broccoli, glucosinolates can be found.
All these substances can be summarized under the umbrella term "secondary plant substances". They are responsible for a large part of the health-promoting effects of fruits and vegetables.
Nature as Inspiration for Medications
Scientists have always used nature as a source of inspiration for potential medications. Aspirin originally comes from the bark of willow trees, painkillers are derived from the dried latex of the opium poppy, and certain cancer medications are obtained from the Pacific yew.
Many other medications are further developments of molecules found in nature. For example, the oldest naturally occurring antibiotic has been continuously developed by attaching molecular structures, thus generating new antibiotics.
What are secondary plant substances
Secondary plant substances are chemical compounds that occur in plants and primarily serve protective functions. They do not play a fundamental role in the metabolism of plants – this task is taken over by "primary" plant substances such as carbohydrates, proteins, and fats. While the primary substances can be counted on one hand, the secondary plant substances present an incomprehensible variety.
So far, about 100,000 different ones are known. Of these, around 5,000 to 10,000 are found in human food. The various secondary plant substances can be classified into different groups based on their chemical structure and functional properties. These groups include polyphenols, flavonoids, alkaloids, glucosinolates, polyamines and many more.Depending on the chemical structure, the effects of specific molecules in the human body differ.
Chlorophyll and phytic acid also belong to the secondary plant substances, but cannot be assigned to any definitive group.
In recent decades, knowledge about the importance of secondary plant substances for human health has increased dramatically. After many smaller studies, large prospective observational studies (cohort studies) and intervention studies with isolated secondary plant substances have been conducted. A few years ago, it was still unclear whether the effects were based on the interaction of various molecules or whether individual substances were responsible for them. In particular, research has shed light on this issue. It is clear that a diet rich in secondary plant substances improves many health indicators.
Importance of secondary plant compounds for the plant world and their effects on human health
Before we look at the effects in the body, let's take a look at the functions in the plant world. The main task of secondary plant substances is to protect plants from harmful influences. They serve as natural defense mechanisms against herbivorous insects, fungi, bacteria, and other pathogens.
They can also help protect flora from UV radiation, heat, cold, and other environmental stress factors.
Based on these remarkable properties, researchers have asked whether some effects can also be transferred to humans, especially since many of the plants are part of our diet. Thousands of studies later, we know the encouraging answer.
Many secondary plant substances have been shown to have antioxidant properties, which means they can combat free radicals and reduce oxidative damage in the body.
Free radicals are unstable molecules that are generated in our body due to various factors such as pollution, stress, smoking, and unhealthy diet. A certain minimum level of "oxidative stress" is indeed vital for survival (among other things, for our immune system). However, an excess of free radicals causes cell damage and is therefore associated with chronic issues such as heart disease and neurodegenerative disorders.
Furthermore, certain secondary plant compounds can reduce inflammation and strengthen the immune system. They also improve blood circulation and support bone health.
What types of secondary plant compounds are there?
Grapes are particularly rich in resveratrol - the most well-known polyphenol.
Polyphenols
Polyphenols are the largest group. They are found in almost all plants, from berries, spinach, to oats and walnuts.
Green tea contains a special subgroup of polyphenols called catechins. This includes the complicated-sounding molecule epigallocatechin gallate, abbreviated as EGCG. EGCG has been shown in animal studies to be effective against high blood sugar, in the prevention of neurodegenerative diseases and in the reduction of cholesterol levels.
Another polyphenol is resveratrol, which is abundant in red grapes. Perhaps you have heard of the French paradox where, despite a high-fat diet with significant nicotine consumption, the French seemed to live longer.This is partly attributed to the high polyphenol content of certain wine varieties, such as Pinot Noir. One of the most well-known researchers on resveratrol is Harvard Professor Dr. David Sinclair.
The following foods are rich in polyphenols
- Spices and Herbs: Spices such as cloves, star anise, and peppermint, as well as dried herbs, are particularly rich in polyphenols.
- Dark Chocolate and Cocoa: Dark chocolate and pure cocoa powder are excellent sources of polyphenols.
- Berries: Blueberries, blackberries, and other types of berries contain high amounts of polyphenols.
- Fruits and Vegetables: Apples, pears, grapes, onions, beets, and kale are some of the fruits and vegetables that are rich in polyphenols.
- Nuts: Nuts, especially walnuts and hazelnuts, are good sources of polyphenols.
- Whole Grains: Whole grains and bread can also provide significant amounts of polyphenols.
- Legumes: Legumes such as beans and lentils are also rich in these beneficial compounds.
- Tea, coffee, and red wine: These beverages are known for their high content of polyphenols. Green tea is particularly rich in catechins.
- Olive oil: Extra virgin olive oil is an excellent source of polyphenols.
In parsley, the flavonoid apigenin is hidden in comparably large amounts. According to studies, it can support NAD levels.
Flavonoids
Strictly speaking, flavonoids also belong to the polyphenols.
Apigenin occurs naturally in some herbs, such as parsley or coriander. But chamomile and celery also contain apigenin. In higher concentrations, this molecule can maintain NAD levels by inhibiting the enzyme CD38 . Higher NAD levels are associated with an extended health span.
In addition to apigenin, luteolin also interferes with NAD metabolism. Luteolin, primarily found in olive oil, rosemary, thyme, or carrots, also positively affects longevity genes, the so-called sirtuins, .
Quercetin, as the third representative in the group supports the immune system and can have a positive effect on allergies.Furthermore, the flavonoid can promote the breakdown of old, non-dividing cells. This process is also referred to as senolysis.
More on the topic: What is quercetin?
What is regeNAD (with luteolin and apigenin)?
The following foods are rich in flavonoids
- Berries: Blueberries, black currants, and blackberries are rich in a type of flavonoids called anthocyanins.
- Onions and cabbage: These vegetables are good sources of flavanols, a subclass of flavonoids.
- Grapes and red wine: Both contain high amounts of flavonoids, especially when the grape skin is involved.
- Tea: Both green and black tea are rich in several types of flavonoids.
- Apples and pears: These fruits are good sources of various types of flavonoids.
- Soy products: Soy contains isoflavones, a special type of flavonoids.
- Peaches, tomatoes, and lettuce
- Citrus fruits: Grapefruits, lemons, and oranges are rich in flavonoids.
- Many herbs and spices: These include, for example, parsley, thyme, and celery.
The quantity and type of flavonoids in foods can vary, depending on factors such as ripeness, storage, and preparation. It is also important to pay attention to high purity and independent manufacturer certifications when looking for corresponding dietary supplements.
In the well-known barberry plants, the alkaloid berberine accumulates. It is a significant natural hope for blood sugar research.
Alkaloids
Alkaloids are characterized by having at least one nitrogen atom in a ring structure. There are many different alkaloids, which possess different properties depending on their molecular structure. Some of them you will surely recognize. Caffeine belongs to this group, as does the painkiller morphine.
Another representative is berberine, which can be found in various plants, such as barberry. In addition to its anti-inflammatory properties and its long use in traditional Chinese medicine, the effect of berberine on blood sugar is currently being studied. Some studies have shown comparably positive effects on blood sugar and insulin sensitivity similar to those of prescription diabetes medications.
Known alkaloids and their use
Among the most well-known alkaloids are:
- Morphine: It is the main alkaloid of the opium poppy and is used as a strong pain reliever.
- Caffeine: This alkaloid, found in coffee, tea, and some other plants, is a stimulant of the central nervous system.
- Nicotine: It is the additive in tobacco and e-cigarettes and has strong stimulating and relaxing effects – but also an extremely high potential for addiction.
- Quinine: This alkaloid, derived from the bark of the cinchona tree, has traditionally been used to treat malaria.
Berberine, the main alkaloid in Berbersome, has long been used in traditional Chinese medicine to treat digestive issues and infections. Additionally, it plays a role in sugar metabolism and is thus a beacon of hope for diabetes research.
Broccoli (especially the sprouts) is particularly rich in glucoraphanin - the direct precursor of sulforaphane.
Glucosinolate
Green vegetables, especially broccoli and spinach, contain another group of secondary plant compounds: Glucosinolates. To be more precise, they contain the substance Glucoraphanin. This is converted with the help of an enzyme into Sulforaphane , which contributes to the slightly bitter taste of these vegetables.
Sulforaphane has, like almost all secondary plant compounds, antioxidant and anti-inflammatory properties. Interesting are the further effects in the body. According to studies, Sulforaphane can lower the blood pressure and assist the liver in detoxification via the Nrf2 pathway .
Glucosinolates in food
Glucosinolates are found in many types of cruciferous vegetables, including:
- Broccoli
- Cauliflower
- Cabbage
- Brussels sprouts
- Radishes
- Arugula
- Garden cress
- Mustard
- Horseradish
In soybeans and wheat germ, the polyamine with the special name is hidden. We are talking about spermidine.
Polyamine
Polyamines occupy a special position. Depending on the definition, they belong to the extended circle of secondary plant substances. One of the most well-known representatives is the molecule Spermidine, which is responsible for cell division and stress tolerance in plants.
In large quantities, it can be found, for example, in soy or in wheat germ. In humans, it is currently being researched further due to its ability to enhance autophagy. Based on the latest research findings, it is suspected that Spermidine has similarly positive effects on the body as fasting Additionally, Spermidine seems to provide protection against neurodegenerative and cardiovascular diseases through improved autophagy.
Polyamines in food
Foods that are particularly rich in polyamines include:
- Meat and fish
- Certain types of cheese, such as Cheddar and Gouda
- Soybeans & Chlorella algae (see spermidine)
- Fermented foods like sauerkraut and kimchi
- Yeast and yeast extracts
High-purity, concentrated secondary plant compounds from MoleQlar
"An apple a day, keeps the doctor away" – what is behind the metaphor?
Does the old saying "An apple a day keeps the doctor away" still hold true today? According to studies, this can be questioned. While industrial agriculture allows us to produce large quantities of food, it often comes at the expense of nutrients.
Not the macronutrients – carbohydrates, fats, and proteins – these remain unchanged, it is primarily about micronutrients. Some studies have shown that the vitamin C content of an apple from conventional agriculture is up to 50% lower compared to organic farming. Additionally, other secondary plant compounds, such as flavonoids, are significantly reduced.
Bioavailability of secondary plant compounds
By definition, bioavailability refers to the extent and speed at which an active ingredient is absorbed by the body and reaches its site of action. This proportion is often low in plant-based foods and thus also in secondary plant compounds. However, various factors can improve absorption.
For example, with polyphenols, bioavailability seems to be enhanced by physiological amounts, heat treatment, and particle size reduction (e.g., grinding) during processing. Additionally, the presence or absence of certain nutrients can influence the bioavailability of polyphenols. A higher fat content and the presence of other polyphenols can increase the bioavailability of polyphenols, while the presence of proteins and antioxidants (vitamins C and E) seems to reduce gastrointestinal degradation.. When it comes to vitamins, however, the research results are mixed.
These fundamental findings were also the basis for the development of dietary supplements. The extraction or isolation of substances from plants not only allows for a higher concentration but also greater purity. If the pure substances are then paired with phospholipids, a significantly increased availability for our body results.
Here you can learn more about phospholipids.
Possible side effects of an overdose of secondary plant substances
Secondary plant substances, including the well-known flavonoids, have numerous health benefits – however, there are several considerations regarding dosage. An overdose can have various consequences.
- Change in hormone activity: Some secondary plant substances, such as isoflavones, can influence the activity of hormones in the body. Isoflavones from soy and red clover resemble estrogens in their structure and can therefore interact with the corresponding receptors in the organism. At very high intake levels, they can disrupt hormonal balance.
- Interactions with medications: Secondary plant substances can interact with certain medications through the liver's CYP450 system and alter their effectiveness. For example, flavonoids can affect blood coagulation and increase the risk of bleeding in individuals taking anticoagulant medications.
- Toxicity: Although very rare, some secondary plant compounds can be toxic in high doses. For example, high doses of capsaicin, the secondary plant compound that gives chili peppers their heat, can lead to gastrointestinal discomfort.
- Allergic Reactions: In some individuals, secondary plant compounds can trigger allergic reactions, especially when consumed in large amounts.
Generally, the amount of secondary plant compounds consumed in a normal diet is usually safe. Problems typically arise from improper or excessive use of dietary supplements. Therefore, pay attention to the dosage recommendations on the packaging and consult with your trusted doctor if you are taking medication.
Sources
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