Isoflavones are part of a group of plant-based chemicals called phytoestrogens. These chemicals act like a weaker form of estrogen in the body. The main isoflavones in soy are
genistein and daidzein
. When you eat soy, bacteria in your intestines break it down into its more active forms.
What are the side effects of soy isoflavones?
- GI upset.
- Constipation, bloating and nausea.
- Allergic reactions (involving rash, itching, and in severe instances, anaphylaxis)
- Loss of appetite.
Where do soy isoflavones come from?
3.3 Soy Isoflavone
Isoflavones are polyphenolic compounds that have estrogen-like effects. They are classified as phytoestrogens because they are plant-derived and have estrogenic activity.
Soybeans
are the richest source of isoflavones, which are predominantly present as glycosides bound to sugar molecules.
Is soy isoflavones the same as soy?
Nutritionally, soy is a good source of fiber, B vitamins, calcium, iron, and other vitamins and minerals. Soy isoflavones are special substances found in soybeans that work in combination with the soy protein, possibly providing additional health benefits.
Does all soy contain isoflavones?
Soybeans are by far the most concentrated source of isoflavones
in the human diet. The highest concentrations of isoflavones are found in soyfoods that aren’t highly processed, such as tofu, soymilk, soynuts, tempeh, miso, and edamame. Soy flour and textured soy protein also contain significant amounts of isoflavones.
Does soy increase belly fat?
After three months, the researchers found, women who drank the soy shake showed less of a gain in abdominal fat, even though both groups showed similar changes in weight and overall body fat. It’s not clear why soy protein
might affect belly fat in particular
, according to Sites and her colleagues.
What are the negative effects of soy?
Dietary supplements containing soy extracts are possibly safe when used for up to 6 months. Soy can cause some mild stomach and intestinal side effects such as
constipation, bloating
, and nausea. It can also cause allergic reactions involving rash, itching, and breathing problems in some people.
Does soy increase breast size?
Soy-based
products won’t increase breast size
either
For that reason, some people think that soy will help their breasts get bigger. As is the case with dairy milk, this is a falsehood. There are no clinical studies, and no evidence, linking phytoestrogens to increased breast size.
Can soy isoflavones cause weight gain?
The results showed that HSI increased the body weight (BW) gain and fat percentage of minipigs (P < 0.05). In addition, the serum concentrations of IGF-I and interleukin-6 were
increased by high levels
of soy isoflavones (P < 0.05).
What fruits are high in isoflavones?
Isoflavones can be found in legumes [10–12], nuts, and some fruits, such as
currants and raisins
[13], coffee [14], and cereals [15], but the most important dietary sources are soybeans and their by-products [10, 12].
Is soy bad for your gut?
Soybeans also contain
“anti-nutrients
” such as phytates and tannins which are compounds that can impair the digestion and absorption of protein, vitamins, and minerals.
What is the healthiest soy?
So stick to simple soy products like
tofu
, tempeh, edamame, soy milk, or miso. These foods may help protect against cancer while providing health benefits.
Is soy bad for women’s hormones?
Soy consumption has been suggested to exert
potentially cancer-preventive effects
in premenopausal women, such as increased menstrual cycle length and sex hormone-binding globulin levels and decreased estrogen levels.
What foods are high in isoflavones?
Soy and its products, and legume seeds (lentils, beans, peas)
are the richest sources of isoflavones, including genistein and daidzein [2]. Moreover, small amounts of isoflavones are also contained in other plant products (cereals, potatoes, vegetables, fruits), as well as in milk, meat, and beer [1, 2].
Is soy isoflavones safe to take?
Soy isoflavones are generally considered safe
[12]. Numerous randomized controlled trials in menopausal women reported that side effects were not significantly different between soy isoflavone and placebo groups [2][13].
How long does it take for soy isoflavones to work?
Soy products can take several weeks or more to reach their maximal benefit. For example, a 2015 review found that soy isoflavones take
more than 13 weeks
to reach just half of their maximum effect. Traditional hormone therapy, on the other hand, takes about three weeks to show the same benefit.
