Phytohormones in Food

Phytoestrogens are chemical substances found in plants that exhibit effects similar to estrogens, the sex hormones found in humans. However, their impact on the body is considerably weaker than that of human hormones. Furthermore, phytoestrogens possess additional properties, such as antioxidant, antimutagenic, fungicidal, and anti-inflammatory. Three primary groups of phytoestrogens can be distinguished: flavonoids (isoflavones, isoflavanones, isoflavanes, and cumestans); lignans (predominantly secoisolariciresinol, matairesinol); stilbenes (predominantly resveratrol). It's worth mentioning that quercetin, a common anti-inflammatory and anti-allergic agent, is also classified as a phytoestrogen, although its effects are substantially weaker.

On average, a person from Europe or America consumes up to 100 times less phytoestrogens than a person from Asia, who can consume up to 100 mg of isoflavones per day. In Japan, they consume up to 200 mg per day. On the other hand, people in the Netherlands, the United Kingdom, or Italy consume only 3-11 mg of isoflavones in their daily diet. So where do we find phytoestrogens? Generally, they are found in plants. Isoflavones are present in soy and its products (e.g., tofu, tempeh), alfalfa, legumes, lentils, and spinach. Interestingly, the amount of isoflavones in soy can range from 560 to 3800 mg/kg. These large differences result from the method of cultivation, location, harvesting, and processing. Large amounts of coumestans can be found in alfalfa, soybeans, spinach, and sprouts. Stilbenes, including the most famous representative resveratrol, are found in grapes and their products. Besides wine, sources of resveratrol can also include mulberries, black currants, and peanuts. Lignans can be found mainly in grains, coffee beans, flaxseeds, and sunflower seeds. Interestingly, they can also be obtained from carrots, onions, apples, cherries, berries, coffee, and tea (black and green).

Several researchers have recorded the positive effects of increasing the intake of phytoestrogens through diet - particularly their anticarcinogenic and protective impact against osteoporosis and heart diseases.

A strong case for the anti-cancer effects are studies in Japan, where isoflavone consumption is the highest in the world. It is also believed that phytoestrogens regulate the apoptosis of cells, helping to reduce the ability of estrogen receptors to act as an antiproliferator. Lignans and isoflavoins therefore inhibit estrogen production in the human body, which in turn reduces the likelihood of causing cancer-dependent cancers. Scientists most often associate anticarcinogenic properties with genistein, which inhibits proliferation and has antimutagenic effects. Research has shown that Asian women who consume a traditional diet are much less likely to develop breast, endometrial, and ovarian cancer than Asian women living in other parts of the world. The Asian diet is rich in soy and other legumes, which provide a high intake of phytoestrogens. Researchers have noted that consuming 20 mg of isoflavones per day reduces the risk of breast cancer by up to 29%. Men living in Asia who consume larger amounts of phytoestrogens are less likely to develop prostate cancer. Research also indicates a lower risk of colon cancer among Asians who follow a traditional diet of the continent.

Women during menopause are at an increased risk of cardiovascular complications, which is due to a decrease in their own estrogen levels. Phytoestrogens not only reduce the unwanted side effects of menopause such as hot flashes, weakness, mood swings and nervousness, but also decrease the overall levels of LDL cholesterol, triglycerides and in this way support the maintenance of the flexibility of blood vessels. Thanks to the ability of phytoestrogens to reduce cholesterol absorption from food and improve the excretion of bile acids, it is possible to reduce the harmful effects on the circulatory system. Genistein, contained in phytoestrogens, decreases platelet aggregation and thereby prevents the formation of dangerous blood clots. Phytoestrogens are also used in hormone replacement therapy during menopause.

During the menopausal period, when the level of estrogen in a woman's body decreases, the risk of osteoporosis increases. Bone mass loss, increased activity of osteoclasts and decreased activity of osteoblasts lead to deterioration of bone structure and significant losses in bone density. However, researchers have shown that phytoestrogens can prevent the onset of osteoporosis. This is achieved through isoflavones that inhibit the activity of osteoclasts (bone-destroying cells) and at the same time stimulate the activity of osteoblasts (bone-forming cells). Furthermore, genistein and biochanin A not only allow for the prevention of bone loss but also limit further losses in women who already have a diagnosis of osteopenia. This is particularly applicable to the vertebrae and the femoral neck. As is known, a fracture of the femoral neck can lead to many complications, including death, in elderly women. Therefore, it is important to ensure a suitable diet rich in calcium, vitamin D, and isoflavones. Already a daily intake of about 90 mg of isoflavones has a positive impact on improving bone density and structure.

Scientists have also proven that a high intake of phytoestrogens in the diet can counteract the skin aging process. Phytoestrogens enhance the production of collagen, allowing the skin to retain its resilience and elasticity for longer periods. Moreover, they have a beneficial effect on skin hydration and the amount of lipids present in the skin layers.

Monitoring phytoestrogen intake in the diet is essential for men, especially those following a plant-based diet, and pregnant women expecting a son. In the case of phytoestrogen intake, the use of the appropriate doses is of particular importance. In a study of a teenage boy following a vegetable-based diet, a number of side effects of high-dose phytoestrogen intakes were observed. However, this boy was consuming about 360mg of plant-derived isoflavones daily. A decrease in libido and erectile dysfunction were also noted. It is worth noting that the dose of plant-derived isoflavones was exceptionally high in this boy, as an average inhabitant of Asian countries consumes about 50 mg of plant-derived isoflavones daily. As can be seen, the difference between these two amounts is significant. Numerous studies confirm the possible impact of high doses of phytoestrogens on fertility and sexual development, however, there are no definitive reports that phytoestrogens taken from food affect changes in testosterone or estrogen levels in men's blood. Furthermore, it has been found that phytoestrogens can have a protective effect in the case of prostate cancer. According to the studies, high intake of phytoestrogens can reduce the risk of prostate cancer by up to 30%. In addition, it has been shown that a high exposure of male fetuses to phytoestrogens can have serious consequences. Men whose mothers consumed large amounts of phytoestrogens during pregnancy are more likely to suffer from epididymal cysts, undescended testicles, reduced sperm count, reduced testicular mass, and disruptions in the structure of the seminiferous tubules. However, it is worth noting that these changes are not uniform and depend mainly on the dose and duration of exposure.

Undeniably, phytoestrogens are a group of compounds with many unknown properties. However, recent scientific findings indicate that these compounds have many beneficial effects, especially for women's health. Their anti-cancer, anti-thrombotic, and menopausal mitigating properties as well as improving the lipid profile and protecting the cardiovascular system are sufficient reasons to incorporate phytoestrogen-rich products into the diet. Nevertheless, men with hormonal problems and expectant mothers should seek advice from a doctor or experienced clinical nutritionist to find out the safe doses of phytoestrogens in their diet. Persons with hypothyroidism should also seek such advice, as isoflavones in soy compete with jodine uptake in the patient's body. However, if you are a healthy person who wants to improve your health in the mentioned aspects, you should not be afraid of phytoestrogens and take their presence in your diet into consideration.