“Notice that autumn is more the season of the soul than of nature” Friedrich Nietzsche
Autumn is probably the most colorful season of the year. It dazzles us with the richness of colors and surprises with the changeability of the weather. It gives us a lot of treasures, such as chestnuts, mushrooms, and ripe fruit and vegetables. Have you wondered how much science we can find in the fall? Let’s take a look on it.
Fall is a fantastic season full of colors. In the world of plants and animals, this is the period of stockpiling before winter. At the turn of summer and autumn, some animals move to warmer climatic zones like the flights of birds such as storks, cranes, and ducks. Monarch butterflies migrate from the United States and Canada to Mexico for winter, bears slowly fall into winter lethargy, and other animals change their diet, adapting it to the available food. Others change their color as they adapt to the coming winter.
In the fall, the leaves of the trees change color and finally fall off before winter, while the color of autumn changes with the climatic zone and the plant varieties belonging to them. Forests in North America and East Asia mostly turn fiery red, while forests in Europe turn bright yellow. Perennial plants, on the other hand, accumulate spare substances in the roots.
The cycle of the seasons results from the tilt of the Earth around its axis and the planet’s orbit around the sun. Autumn begins when the sun appears at the intersection of the ecliptic and the celestial equator. Then, there is a phenomenon called the equinox (the length of the day is similar to the length of the night). Autumn brings a cooling down of the air; how much it feels depends on the place on Earth.
In different cultures, this season is associated with thanksgiving and rebirth. In Judaism, commemorate the time spent in exile through thanksgiving, the so-called Sukkot festival. In turn, Catholics celebrate All Saints’ Day when people bring flowers to their graves. There are also many allegories to autumn in art, like Autumn painting by Art Nouveau artist Alphonse Mucha.
In some countries, fall is also the time of seasonal sweets, like in Japan. It is about Momiji tempura, of course. This dish is the leaves of Japanese maple prepared in the process of deep-frying. Before they reach our table, they are stored in salt barrels for a year. As you can see, autumn gives us many treasures, both for body and spirit, but that is not the end of the very long list of goods served by autumn.
Mushrooms
Forests are full of mushrooms for the entire fall. Of course only some of them are edible, while Aside from a taste that many people value, mushrooms have many nutrients to offer. Some contain considerable amounts of linoleic and oleic acids – unsaturated fatty acids of the omega-6 type [1]. These components are a precious part of one’s diet, as they lower the levels of unfavorable cholesterol and higher up the levels of the favorable one. Additionally, mushrooms – especially when dried – are shown to have a lot of beneficial minerals and vitamins in them – which ones precisely depending on the type of mushroom. Mainly, they contain calcium, potassium, and phosphorus [2]. Those elements are essential for human functioning, and mushrooms are a valuable source of those. On the other hand, when dried, they can contain up to 65% of carbohydrates, with a big part of those being fibers [2]. As a result, they are a low-calorie food, excellent for the human gut microbiome.
Chestnuts
Another symbol of fall are goods falling from the trees. One of the most popular symbols of fall is the chestnut. There are various types of chestnuts: ordinary (otherwise white, common, horse, bitter chestnut, wild chestnut), yellow, red (peacock chestnut), red (cross of European and blood chestnut), and small-flowered. The oldest known tree of this species grows in Sicily, on the eastern slope of Etna volcano – The Hundred-Horse Chestnut. It belongs to the European chestnuts, so-called sugar chestnuts, or Spanish chestnuts. It is estimated to be between 2,000 and 4,000 years old.
One of the things about horse chestnuts that can benefit us is the extract, which contains many interesting chemical compounds. The main active ingredient of horse chestnut extract is aescin. Medicines containing this substance have an anti-inflammatory effect, relieve pain and reduce swelling. It improves blood flow, reduces brittleness, restores elasticity and the proper tension of blood vessels [3]. It helps with hemorrhoids, which are swollen veins around the anus and rectum [4, 5]. Aescin may reduce the growth of cancer cells in cancers such as liver cancer, leukemia, and multiple myeloma [6]. Other compounds that the horse chestnut extract contains are antioxidants. They can prevent cell damage caused by unstable molecules called free radicals [7]. For the treatment of leg ulcers and frostbite, it is recommended to use an ointment with horse chestnut extract. Other compounds are flavonoid compounds, i.e. substances that act as dyes, antioxidants and natural insecticides and fungicides that protect against attacks by insects and fungi [8]. In particular, it contains quercetin and kaempferol which have strong antioxidant properties. Chestnut tincture improves blood circulation and removes puffiness.
Raw horse chestnut extract can also cause side effects, including itching, nausea or gastrointestinal problems, muscle aches, and headache [9]. For the safety of people suffering from diseases such as kidney or liver disease and bleeding disorders, it is better to avoid this drug. The leaflet also contains information that horse chestnut extract should not be combined with aspirin, Plavix, warfarin, and other anticoagulants or antiplatelet drugs [10].
Acorns
In childhood, each of us made men and beads from what autumn provided us. In addition to chestnuts, we used acorns (the fruits of the oak tree) for this purpose. Can acorns be edible? These oak fruits belonged to the group of nuts and were eagerly eaten by our ancestors. Acorns do contain tannins, i.e. bitter plant compounds that can be harmful if consumed in excess. They cause a reduction in the absorption of beneficial substances by our body. Fortunately, most of them are flushed out of the acorns during soaking and cooking [11]. As a reward, they contain potassium, iron, vitamins A and E. They can supply man with such antioxidants as catechins, resveratrol, quercetin, and gallic acid, being silent heroes in the fight against cell damage [12]. Like most autumn goods, they reduce the risk of heart disease, diabetes, and cancer while containing antioxidants. As sources of valuable fiber, they keep the intestines balanced and thus counteract obesity, diabetes, and intestinal diseases [13].
Mountain ash
Mountain ash, so-called Rowan berries, have red or bright orange fruit. Raw is inedible due to many toxic ingredients (parasorbic acid) and the bitter taste. This situation changes after blanching (freezing and immersing in boiling water for a while) [14]. This operation deprives them of both properties. It contains vitamins C, E, P, K, B3, A, sugar, sorbose, tannins, and pectins. Rowan is a real wealth of antioxidants that serve as a protective shield against chronic diseases, including cancer. It has a positive effect on the mucous membranes and the digestive system. Mountain ash is used in catarrhs of the intestines, chronic diarrhea, and various liver and gallbladder diseases. It was from this plant that sorbic acid was first obtained by extraction. This substance helps to reduce the influence of microbial and bacterial factors on the skin and body. As a result, it is widely used in the cosmetics industry.
Heather
One of the most beautiful autumn views is the stunning moors, shimmering in various purple, pink, and white shades. This plant has been present in folk medicine for centuries. It contains many beneficial substances, such as tannins, arbutin, saponins, carotene and flavonoids, quercitrin, and myricitrin. It removes excess uric acid from the body that has caused kidney stones or sore joints associated with arthritis. Heather tea has strong diuretic, antiseptic and disinfectant properties. Heather is also one of the ingredients of the ointment for arthritis and rheumatism [15]. When you have problems with the joints, pour boiling water over the heather, let it stand for a few hours, and then add it to the bath.
Colorful leaves
In fall, the amount of green pigment in leaves drastically increases. The pigment that makes the leaves green is called chlorophyll, and it is responsible for a complex process called photosynthesis. Thanks to that process, the plant can produce sugars and carbohydrates, releasing oxygen. When the fall is coming, the number of chlorophyll drops and other natural pigments present in leaves appear. One of them is yellow, and orange pigments are called carotenoids. The same dyes are responsible for making the orange color of tomatoes, carrots, tomatoes, pumpkin, and even paprika. Another dye naturally present in leaves is xanthophylls. They give the plant a bright orange color similar to the carotenoids. The next group of compounds present in leaves is anthocyanins that protect the chlorophyll against overexposure to sunlight or high temperatures. In fall, when there is little or no chlorophyll, the intensity of such pigment is finally visible. All these pigments give the plant a fantastic palette of colors, making fall the most colorful season.
The fruits and vegetables of autumn
Many fruits and vegetables ripen in autumn, which have a remarkably beneficial effect on human health, such as apples, pears, winter squash (pumpkins), broccoli, beets, cucumbers cauliflowers, green beans, kale, or cranberries. They all contain many beneficial ingredients.
Apples
The fruit of Paradise and their healing properties were known as early as around 6500 BC, in the area between the Black Sea and the Caspian Sea, where they originate. They were a delicacy of the ancient Romans and Greeks. They contain manganese, copper, and vitamins A, E, B1, B2, and B6. All these substances help to strengthen our immunity. They are a source of fiber and polyphenols (compounds with potent antioxidant properties) [16]. As a result, they reduce the risk of heart disease, as fiber helps to lower blood cholesterol [17]. These supplements reduce the risk of developing type 2 diabetes [18]. Fiber regulates the work of the intestines, protecting against constipation and other intestinal diseases, including colon cancer. White-flesh fruit such as pears and apples also reduce the risk of strokes. In natural medicine, boiled or grated apples are given to children suffering from diarrhea, while in the case of adults, they provide relief from indigestion and peptic ulcer disease. Apples also contain antioxidants that can help us fight asthma. Paradise fruits are our ally in the fight against the passage of time. They contain acetylcholine, a neurotransmitter that can decline with age. Its lack may result in Alzheimer’s disease [19]. It is worth eating apples.
Pears
Other treasures of autumn are pears. Another treasure of autumn is pears. They are the natural source of potassium, vitamin A, C, B6, and K, calcium, iron, magnesium, riboflavin, and folate. Vitamin A is beneficial for maintaining healthy and beautiful skin, hair, and nails. They also contain zeaxanthin and lutein (yellow-orange pigments from the group of carotenoids, which, for example, depend on good eyesight). These substances help maintain youthful skin by reducing age spots and wrinkles. The high content of minerals in pears helps our bones protect against osteoporosis. Pears contain antioxidants and a soluble fiber called pectin. Pectin nourishes gut bacteria and improves gut health. These fruits have a positive effect on our digestive system. Regular consumption of pears lowers blood pressure, which prevents cardiovascular disease [20]. They also strengthen our immune system.
Pumpkins
Winter squash, also called pumpkin, is one of the symbols of Thanksgiving and Halloween in North America. It is a natural vitamin treasure. There are mainly two parts of the pumpkin that are eaten by humans – pulp and seeds. The pulp contains polysaccharides (including good fiber), minerals, and proteins, whereas the seeds have high lipids, potassium, and phosphorus level. However, it is worth stressing that different types of pumpkins may have different amounts of various nutrients, including essential vitamins and minerals.
Nonetheless, pumpkins are characterized by higher chrome amounts than other vegetables [21]. Chrome is an important element in a human diet – it is needed for proper fat and sugar metabolisms. It can also be helpful to people with diabetes, as it increases the strength of insulin. As a result, less insulin is needed to lower blood glucose levels [22].
SUMMARY
Most of us feel sorry for the passing of summer. However, autumn surprises us with its weather, richness of colors, which makes us feel better. When the leaves fall and get sad, it is best to cheer up your mood with a bit of ginger, cinnamon, and nutmeg. These spices are highly beneficial to our health. Nutmeg kills germs, ginger improves circulation, and cinnamon lowers inflammation in the body, just in time for rainy weather. In addition to seasonal colds, it brings us unique benefits. As the temperature drops, we sleep better.
This article is a joint work of Zuzanna Kozlowska (Faculty of Chemistry, University of Warsaw), Agnieszka Pregowska (Institute of Fundamental Technological Research, Polish Academy of Sciences), and Magdalena Osial (Faculty of Chemistry, University of Warsaw). Image Credit: Agnieszka Pregowska.
References
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