SOY: GOOD OR BAD?

April 17, 2017

Glycine max, commonly known as soybean or soya bean, is part of the legume family, and native to East Asia. It is grown for its edible bean which has high levels of protein and has a wide variety of uses. Soybeans have only been introduced to the Western world since the 20th century, and are a relatively easy to grow and hardy plant, due to their adaptation to a variety of soils and climates. The most common type of soybean is a yellow colour, but rarer varieties can come in black, brown, or green colours.

Some uses for this bean include: animal feed (defatted soybean meal), meat and dairy substitutes, industrial products such as lubricants, plastics, and waxes, and the production of foods such as soy vegetable oil, soy milk, tofu, tofu skin, soy sauce, fermented bean paste, natto, and tempeh.

Any given area of land planted with soybeans can produce more protein than land planted with other crops, or especially, meat animals.

 

FOR:

The soybean is:

  • High in fibre
  • High in protein
  • High in phytoestrogens
  • High in antioxidants
  • Low in saturated fat
  • Cholesterol free
  • Dairy free
  • High in omega-3 fatty acids
  • Full of vitamins  K, riboflavin, folate, B6, thiamine, and C
  • High in iron, manganese, phosphorous, copper, potassium, magnesium, zinc, selenium, and calcium

 

Health benefits include:

  • Aids with diabetes: Soybeans are effective for preventing and managing this disease because they have an ability to increase insulin receptors in the body. They are also a good source of protein for diabetics as they contain no starch.
  • Cancer prevention: Soybeans contain a number of components which protect the body against cancer, including: isoflavones, lectin, and lunasin. They are full of antioxidants which work by seeking out and neutralizing free radicals, the dangerous cancer causing by products of cellular metabolism. Also, the high fibre content of soybeans is thought to greatly reduce the chances of colorectal and colon cancer, as fibre helps to ease the digestive process, therefore putting much less pressure on the gastrointestinal system.
  • Treats and alleviates menopausal symptoms: Soybeans contain phytoestrogens, which are naturally occurring chemicals which mimic the action of the hormone estrogen, at a much less powerful level. Due to the presence of phytoestrogens, the consumption of soy can alleviate menopausal symptoms by acting as a mild form of hormone replacement.
  • Improves sleep: Due to the positive effect soybeans have on metabolism, they aid in reducing sleep disorders and the occurrence of insomnia. Soybeans are also high in magnesium levels, which are directly linked to improving the quality, duration, and restfulness of your sleep.
  • Increased bone health: Soy consumption reduces the risk of osteoporosis, a condition characterized by reduced bone density and an increased risk of fractures. The beneficial effect soybeans have on the bones is due to the isoflavones present in the plant
  • Protects against coronary heart disease: Soybeans are known to decrease the levels of total and ‘bad’ LDL cholesterol levels, both of which are known risk factors for coronary heart disease. Studies have also shown that the consumption of soy slightly increases the levels of ‘good’ HDL cholesterols. There are two particular fatty acids that are essential for a healthy system, these are: linoleic acid, and linolenic acid. These two fatty acids are abundant in soybeans and are required to regulate smooth muscle function in the body, and maintain appropriate blood pressure.
  • Improves metabolism: Soybeans are one of the best sources of protein. When you have enough protein in your body, your overall system and metabolic functions get a major boost.
  • Improves digestive health: One of the most common missing factors in an individual’s diet is fibre. Fibre is essential for digestive health, helping to prevent conditions such as constipation, which can lead to colorectal cancer. Soybeans are so beneficial to digestive health because they have such high concentrations of fibre.
  • Lowers blood pressure
  • Improves blood vessel health: Proteins are the building blocks of cells, blood vessels, and almost every essential part of the human body. Soybeans contain large amounts of proteins which improve the health of cells and blood vessels, and also aids in their repair or regrowth. Soybeans also contain omega-3 and omega-6 fatty acids, along with phyto-antioxidants which together act to protect blood vessels from lesions and haemorrhage. These compounds bind to the blood vessel lining and defend lining cells from free radical attacks, and cholesterol deposits. They also improve the flexibility of the blood vessels, making them much more resilient to blood pressure changes.
  • Aids with the management of endometriosis
  • Improves bone health: Soybeans have quite high levels of a variety of minerals, including calcium, magnesium, selenium, copper, and zinc, all of which are essential for bone health. These minerals are required for promoting osteotrophic activity, which allows for bones to grow, and increases the rate of bone healing. It can be a long term solution for osteoporosis.
  • Improves red blood cell health and circulation: Two of the abundant minerals found in soybeans are iron and copper, which are essential for the formation of red blood cells. This aids to prevent certain conditions like anaemia. With a sufficient amount of red blood cells, the body is able to circulate blood properly; ensuring extremities and essential organ systems are able to function efficiently.
  • Balances hormones: Phytoestrogens have been found to help block the effects of excess estrogen in the body, balancing the ratio between estrogen and progesterone.
  • Reduces/prevents birth defects: Soybeans are rich in Vitamin B, particularly folic acid (B9). Folic acid helps the body to make healthy red blood cells, and is important for maintaining rapid cell division and growth during pregnancy. A deficiency of folic acid in pregnant women can lead to underweight infants, and neural tube defects.
  • Prevents weight gain: Soybeans are known to be efficient appetite suppressors, and are therefore efficient at eliminating over eating and preventing obesity and weight gain.
  • Alternatively aids with healthy weight gain: As soybeans are high in fibre and protein, ingesting larger amounts of them can lead to weight gain. This weight does not have an unhealthy high-fat or high cholesterol nature, therefore protecting against conditions such as diabetes or cardiovascular disease.

 

 

AGAINST:

Soy allergy: Soybeans are among the 8 food types considered to be major food allergens. This allergy is triggered by soy proteins, glycinin, and conglycinin.

Soybeans are widely used in food products around the world. The food additive lecithin is made from soybeans and is often used in the production of chocolate, baked goods, cheese, butter, margarine, sauces, and other dairy products.

Symptoms of soy allergy:

  • Itching
  • Tingling sensation of the mouth area
  • Hives
  • Wheezing or breathing difficulties
  • Nausea
  • Diarrhoea
  • Flushed skin
  • Anaphylactic shock
  • Drop in blood pressure
  • Dizziness
  • Disturbed sleep

 

Other health problems linked to soy:

  • Due to the phytoestrogens found in soybeans, some men occasionally develop a hormonal imbalance if they consume large amounts. Imbalances can lead to: infertility, sexual dysfunction, lower sperm count, and an increased risk of certain cancers.
  • There are anti thyroid compounds (isoflavones) found in soy that can disrupt the activity of the thyroid gland, resulting in goiters (an abnormal enlargement of the thyroid gland), and interruptions of hormonal activity. These isoflavones do this by suppressing the formation of thyroid hormones in both animals and humans.
  • Soybeans contain phytates which can lessen the absorption of certain nutrients, particularly minerals. Levels of these phytates are higher in the processed form of soy.
  • The phytoestrogens in soy have been hypothetically linked with increased breast tissue in women, therefore possibly increasing the risk of breast cancer. This is not proven and more studies are required.
  • Flatulence and diarrhoea: Like many other plant based foods, especially beans, soybeans are high in insoluble fibre (raffinose, and stachyose), which may cause flatulence and diarrhoea in sensitive individuals. These insoluble fibres may also worsen the symptoms of IBS (Irritable Bowel Syndrome).
  • High doses of soy may not be safe for people with, or recovering from breast cancer. This is because the phytoestrogens may ‘feed’ the hormone dependant tumours, and work against conventional treatments which work by blocking the effects of estrogen.
  • A high number of soybean crops (particularly in places like the U.S.) are genetically modified and sprayed with herbicides which have been associated with adverse health effects.
  • Hexane is a solvent used to extract oil from soybeans. It is a neurotoxin, and chronic exposure may be linked to neurological disorders. If the food product contains soy protein isolate, soy protein concentrate, or textured vegetable protein, it has likely undergone hexane processing.
  • Some studies suggest that soy can aid with memory, while others suggest that eating soy long term in large amounts may lead to memory problems, especially in older people. More study is needed.

 

The takeaways:

  • Soy should only ever be eaten cooked
  • Soy is healthiest when fermented: Some studies suggest that there are some ‘anti-nutrients’ or toxins naturally present in soybeans, and the fermentation process destroys these toxins.
  • Avoid overly processed, GMO, or hexane treated soy products
  • Soy has a large number of health benefits, but also may have some negative effects to certain individuals
  • Soy is generally safe for consumption. Exceptions are: people with soy allergies, infants, and current/recovering breast cancer patients
  • Soy should be eaten in moderation
  • It is not advisable to feed infants on soy based formulas as rodent based  studies suggest there may be negative impacts on the infants health both short and long term. More study is needed on the subject.
  • The vast majority of studies suggest that soy has more beneficial impacts on an individual’s health rather than negative ones

 

REFERENCES:

http://www.soya.be/soybeans.php

http://www.australianoilseeds.com/soy_australia/soybean_information

https://en.wikipedia.org/wiki/Soybean

https://www.britannica.com/plant/soybean

https://www.betterhealth.vic.gov.au/health/healthyliving/soybeans

http://www.mayoclinic.org/diseases-conditions/goiter/home/ovc-20264589

https://www.organicfacts.net/health-benefits/cereal/soybeans.html

http://www.whfoods.com/genpage.php?tname=foodspice&dbid=79

https://authoritynutrition.com/foods/soybeans/

https://www.womentowomen.com/nutrition/the-health-benefits-of-soy/

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http://www.livestrong.com/article/441255-what-is-the-difference-between-skim-milk-fat-free-milk/

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http://www.livestrong.com/article/457136-dosage-of-soy-isoflavones/

https://www.smallfootprintfamily.com/why-soy-is-bad-for-you-and-the-planet

http://www.everydayhealth.com/diet-nutrition/the-truth-about-soy.aspx

https://www.thespruce.com/health-benefits-and-risks-of-soy-694730

https://www.hsph.harvard.edu/nutritionsource/2014/02/12/straight-talk-about-soy/

http://www.shape.com/healthy-eating/diet-tips/ask-diet-doctor-last-word-soy-protein-isolate