Koji Su Nuspojave Soje?

2024 Autor: Cecilia Ryder | [email protected]. Zadnja promjena: 2023-12-17 14:20

Soja je široko konzumirana mahunarka. Osnovna je azijska prehrana i koristi se kao sastojak nekoliko prerađenih namirnica. Proteini u soji (sojini proteini) mogu zamijeniti životinjske proteine u vašoj prehrani, a dobivaju se nakon uklanjanja vanjske ljuske soje i njihovih masnih kiselina (1), (2).

Iako je soja bogata hranjivim sastojcima poput kalcija, željeza, cinka i aminokiselina, mogla bi izazvati određene nuspojave (3).

Kada se prekomjerno konzumiraju, mogu ometati lijekove za regulaciju štitnjače i uzrokovati neravnotežu testosterona, alergije i proliferaciju raka.

Također, dugotrajna upotreba viška sojinih proizvoda može biti nesigurna. U ovom postu raspravljamo o soji i njezinim mogućim štetnim učincima. Nastavi čitati.

Sadržaj

• Što je glavno pitanje soje?
• Što se događa kada konzumirate soju? Što uzrokuje štetne učinke?
• Koji su štetni učinci soje (proteina soje)?
• Koje proizvode od soje trebate izbjegavati?
• Koliko je soje sigurno jesti dnevno?
• Je li previše prehrane sojom štetno?

Što je glavno pitanje soje?

Glavni problem soje je njezin sadržaj izoflavona.

Soja je rezervoar fitoestrogena (izoflavona), koji su strukturno i funkcionalno slični estrogenu u vašem tijelu (3). Izoflavoni su klasa fitoestrogena (zvani i proteini soje) koji se nalaze u soji i sojinim proizvodima. Sljedeća tablica trebala bi vam dati ideju o sadržaju izoflavona u različitim sojinim namirnicama.

Nefermentirana sojina hrana	Sadržaj izoflavona (mg)
sojino mlijeko, 1 šalica	6
tofu (skuta od graha), mekana, 3 unče	20
soja, zrela, kuhana, ½ šalice	55
soja, suho pečena, 1 oz.	40
edamame, kuhano, ½ šalice	16
sojin sir, 1 oz.	2
pljeskavica od soje, 1 pljeskavica	5
Fermentirana sojina hrana	Sadržaj izoflavona (mg)
miso, 3 oz.	37
natto, 3 oz.	70
tempeh, kuhan, 3 oz.	30
soja sos, 1 žlica	0,02

Izvor: Harvard THChan School of Public Health

Fitoestrogeni od soje korišteni su za nadoknađivanje nedostatka estrogenskog hormona. Sojini proteini dio su nadomjesne terapije estrogenom koja se daje ženama koje prolaze kroz menopauzu (3).

Neke epidemiološke studije sugeriraju da unos fitoestrogena hranom, između ostalih simptoma, može smanjiti učestalost postmenopauzalnih kardiovaskularnih bolesti, osteoporoze i valunga. Kontrastni podaci također su izvijestili o potencijalu fitoestrogena u prevenciji raka dojke i prostate (3).

Međutim, koristi od soje nisu jasne. Zapravo, neke druge studije također navode da bi sojini proteini mogli nanijeti potencijalnu štetu (3).

Što se događa kada konzumirate soju? Što uzrokuje štetne učinke?

Kada konzumirate soju (proteini soje) u bilo kojem obliku, izoflavoni soje (fitoestrogeni) vežu se za receptore estrogena u vašem tijelu. Ti se fitoestrogeni natječu s prirodnim estrogenom da bi se vezali za receptore. To rezultira slabim estrogenim ili anti-estrogenim djelovanjem. Drugim riječima, izoflavoni soje mogu učiniti prirodni estrogen u vašem tijelu manje učinkovitim (3), (4).

Takve interakcije mogu dovesti do hormonske neravnoteže i izazvati spolne promjene kod djevojčica. Oni također mogu imati anti-androgene učinke kod muškaraca. Muškarci mogu početi rasti dojke (ginekomastija) i osjetiti pad koncentracije sperme kada su na dijeti od visoke soje (3).

Predoziranje izoflavonom tijekom duljeg razdoblja može stimulirati endometrij (maternicu) i dojke kod žena. Stoga se svima koji su liječeni od raka dojke obično preporučuje izbjegavanje sojinih proteina (3).

Fitoestrogeni mogu utjecati na nekoliko fizioloških i patoloških procesa u tijelu. Visoke doze izolata soje mogu uzrokovati štetne učinke na reprodukciju, kožu, pregradnju kostiju, kardiovaskularni sustav, živčani sustav, imunološki sustav i metabolizam.

Pogledajmo detaljno štetne učinke soje (proteina soje).

Koji su štetni učinci soje (proteina soje)?

1. Može ometati regulaciju štitnjače

Sojina hrana može povećati rizik od razvoja hipotireoze kod osoba s oštećenim radom štitnjače. Takve osobe mogu razviti gušu i autoimune bolesti štitnjače. Ovaj se rizik dodatno povećava kada je unos joda kod pojedinca nizak (5).

Utvrđeno je da izoflavoni soje inhibiraju aktivnost enzima zvanog štitnjača peroksidaza. Ovaj enzim potreban je za sintezu hormona štitnjače. Zbog toga se možete suočiti s rizikom od hipotireoze kada jedete puno sojinih proteina (6).

Sojini proizvodi također ometaju apsorpciju levotiroksina (L-tiroksin), lijeka koji se koristi za liječenje nedostatka hormona štitnjače (7). Budući da se čini da sojini proteini mijenjaju dostupnost lijekova, može vam se savjetovati da ne konzumirate sojine proteine ako imate neravnotežu štitnjače.

Međutim, čini se da samo visok unos sojinih izoflavona ne povećava rizik od hipotireoze, osim ako nije povezan s neadekvatnom konzumacijom prehrambenog joda. Stoga je utjecaj sojinih proteina na štitnjaču diskutabilan. S tim u vezi potrebno je više istraživanja.

2. Može uzrokovati neravnotežu testosterona

Istraživanje je provedeno na 12 muških ispitanika koji su svakodnevno konzumirali 56 g izolata sojinih proteina tijekom četiri tjedna. Kao rezultat, njihova se razina testosterona u serumu smanjila za 19% (8). Iako su podaci bili nedosljedni, utvrđeno je da protein soje smanjuje razinu testosterona u serumu kod zdravih muškaraca.

Kaže se da sojini proteini imaju štetne učinke na reproduktivnu funkciju muškarca. Međutim, u tom pogledu ne postoje posebne studije. Neke studije na životinjama, zapravo, navode da izoflavoni soje ne vrše feminizirajuće učinke na muškarce (9).

Većina promatranja temelji se na laboratorijskim studijama i istraživanjima na životinjama. Stoga odnos između izoflavona i testosterona soje nije uvjerljiv (10).

3. Svibanj izaziva preosjetljivost (alergija)

Proizvodi od soje mogu kod djece i odraslih izazvati alergije ili preosjetljivost. Alergija na soju često počinje u dojenačkoj dobi, reakcijom na proizvode od soje-soje koji mogu izazvati alergije ili preosjetljivost kod djece i odraslih. Alergija na soju često započinje u dojenačkoj dobi reakcijom na adaptiranu hranu za dojenčad na bazi soje. Međutim, većina djece preraste alergiju na soju (11).

Općenito, alergija na soju je neugodna, ali nije ozbiljna. Alergijska reakcija na soju rijetko je zastrašujuća ili smrtonosna. Simptomi alergije na soju mogu uključivati trnce u ustima, ekceme ili svrbež kože, piskanje, proljev, bolove u trbuhu, povraćanje i crvenilo kože (ispiranje) (12).

If you experience any of these symptoms, you may have a soy allergy. Get tested to confirm the allergy. If tested positive, you may be advised against having soy products/isoflavones.

4. May Increase The Risk Of Cancer Proliferation

Soy isoflavones (one of them being genistein) may stimulate the proliferation of cancer cells in your body. This is especially true in the case of estrogen-dependent breast cancer, as soy isoflavones tend to have estrogenic effects (13).

As per animal studies, genistein may deregulate the cell cycle and trigger tumor development. It acts by triggering the estrogen receptors (14).

Contrarily, human studies show an inverse relationship between cancer and isoflavones. Soy intake was also found to reduce the incidence and death rate caused due to breast cancer. This could be because of the anti-estrogenic effect exerted by phytoestrogens (13).

The amount and source of soy isoflavones also greatly impact breast cancer risk (14).

5. May Trigger Alzheimer’s Dementia

Traditionally, soy foods were used in cooking only after fermenting. This two-step routine would destroy most of the anti-nutrients in soy, such as isoflavones (like genistein and daidzein) and DNA-altering enzymes (like topoisomerases) (15).

When you eat unfermented, cooked/uncooked soy foods, these anti-nutrients may affect the vital systems of your body, including your brain (15).

These anti-nutrients in soy could have detrimental effects on many individuals. Soy isoflavones could increase the risk of Alzheimer’s dementia (15).

If you are dealing with dementia or have a family history of this condition, it is safe to reduce your soy consumption (15).

6. May Cause Infant Health Issues

Infant food formulas contain fair amounts of soy protein/isoflavones. Infants who are fed these formulas are exposed to 5.7–11.9 mg isoflavones/kg body weight during the first four months of life (16).

These kids are exposed to 6–11 times higher levels of isoflavones than adults. This could lead to disturbances in the reproductive health and endocrine function in the child. The major isoflavones, daidzein and genistein, preferentially bind to the estrogen receptors in the body (16).

However, these conclusions are based on animal studies. Human studies may give a different picture. Moreover, currently available soy-based formulas show no overt toxicities in healthy infants (16), (17). Hence, check with your pediatrician before giving soy-based formulas to your child.

7. Unsure Osteoprotective Effects

Soy protein has shown to conserve bone mineral density, particularly in postmenopausal women. In perimenopausal women, the soy isoflavones were shown to prevent bone loss from the lumbar spine. These compounds had no significant effect (neither positive nor negative) on bone formation and/or bone resorption (18).

In some cases, the mineral balance could be impaired with soy consumption. Soybeans contain (by weight) about 1–3% phytic acid (also called phytate). Phytic acid is an anti-nutrient that binds to minerals like zinc, iron, and calcium. Along with soy isoflavones, phytic acid also may decrease their bioavailability (18).

However, a major chunk of literature highlights the osteoprotective effect of soy protein. Further research is needed to determine the precise impact of soy protein/foods on bone density and other related diseases (19).

Most of the research on soybeans and soy protein is still unclear. While in some studies they seem to promote health, certain other studies tend to state the potential harm they may cause. However, this does not mean you have to totally be off soy. There are a few specific soy products you may want to avoid.

Which Soy Products Should You Avoid?

Moderation is important, and so is eating right. Choosing the right kind of soy products can protect you from the adverse effects mentioned above.

When given a choice between natural soy foods and soy protein isolate, go for the natural options. Avoid industrial soy foods if you have iodine deficiency or thyroid imbalance (15).

Whole soy foods are mostly fermented and cooked in a healthier manner. You can take tofu, edamame, soy milk, tempeh, miso, and natto a few times every week.

How Much Soy Is Safe To Eat In A Day?

According to the US FDA, daily consumption of 25 g of soy seems to be safe. This amount of soy could also help lower cholesterol levels (20).

It also is believed that the intake of 50 g of soy protein per day could help prevent heart disease, diabetes, and estrogen-dependent cancers. However, more research is warranted.

There is limited information on the excess intake of soy protein/soybeans. But we don’t recommend you take more than 25 grams per day.

Is Eating Too Much Soy Harmful?

There is little information about the toxicity of soy protein. In limited doses, soy protein may be helpful for women who are at a high risk of breast cancer (21).

Some studies reported very few drug-related adverse events, which were mild. In very few cases, high levels of soy isoflavones adversely affected blood pressure levels (22).

Hence, it is important you talk to your healthcare provider about a suitable dosage for you.

Conclusion

Soy protein could be the reason Asians have historically had lower rates of cardiovascular disease. Their menopausal symptoms and incidence of breast cancer, diabetes, and obesity are also lower than their Western counterparts (23).

There is substantial yet unclear evidence stating the adverse effects of soybeans and soy protein/foods. Soy isoflavones may disturb the hormonal balance, stimulate cancer proliferation, and trigger allergies.

Hence, choose your soy portions carefully. Pick fermented soy foods over protein or isoflavone isolates. Follow the instructions by your physician/nutritionist and stick to the recommended intake limit.

23 sources

Stylecraze ima stroge smjernice za izvor i oslanja se na recenzirane studije, akademske istraživačke institucije i medicinska udruženja. Izbjegavamo koristiti tercijarne reference. Možete pročitati više o tome kako osiguravamo da je naš sadržaj točan i aktualan čitajući našu uredničku politiku.

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