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GYM CONQUER ジム筋華のブランドイメージ

Soy Problems! The Truth to Defy Fate

"Good grief..." Soy is widely known as a health food, but it also has its share of problems. Issues like genetically modified organisms, isoflavones, goitrogens, phytic acid, and lectins are associated with soy. Let's unravel each of these problems and provide effective solutions!

A dynamic illustration of a character inspired by Jolyne Cujoh from JoJo's Bizarre Adventure, standing in her iconic JoJo pose. She has long, light green hair styled in two buns with loose strands and wears a green patterned outfit. She stands fiercely, with her body twisted and one arm outstretched while the other rests on her hip. Surrounding her are stylized symbols representing various issues related to soy (genetically modified organisms, isoflavones, goitrogens, phytic acid, lectins). The background features swirling energy and glowing elements, symbolizing the battle against these soy-related concerns. English onomatopoeia like 'ORA ORA' and 'MENACING' add to the intense atmosphere. The scene is vibrant, colorful, and dramatic, capturing the essence of a JoJo-style confrontation.

Problems with Genetically Modified Organisms

The safety of genetically modified (GM) foods is a controversial topic. GM organisms refer to crops modified to resist herbicides like glyphosate. In 2015, the IARC classified glyphosate as "probably carcinogenic," but this was based on animal studies, not humans. Many agencies, including the EFSA and EPA, consider glyphosate safe. However, it is prudent to opt for domestic soy or products labeled Non-GMO if this concerns you.

Problems with Isoflavones

Isoflavones have estrogen-like effects, which can increase the risk of endometrial hyperplasia in women if consumed in large amounts. The Ministry of Health of Japan's guidelines state that the intake of soy isoflavones should not exceed 75 mg per day, and supplements should not exceed 30 mg per day. Long-term studies have found no significant problems with soy intake, but it is best to avoid excessive consumption of soy milk.

Problems with Goitrogens

Goitrogens inhibit iodine absorption, which can cause thyroid enlargement. Genistein in soy has this effect, but due to the high intake of iodine in the Japanese diet, the negative effects are minimal. In fact, goitrogens in soy may protect against excess iodine.

Problems with Phytic Acid

Phytic acid inhibits the absorption of minerals but also helps eliminate heavy metals like mercury and lead from the body. Phytic acid is present in many other foods like oatmeal and corn, so it is not unique to soy. For older men, the ability of phytic acid to reduce iron can be beneficial for cardiovascular health.

Problems with Trypsin Inhibitors

Trypsin inhibitors in soy interfere with protein digestion but are largely destroyed by cooking. Soy products like tofu and soy milk have very low levels of trypsin inhibitors, so they do not pose a significant problem.

Problems with Lectins

Lectins are proteins that can cause red blood cells to clump together and are believed to contribute to leaky gut syndrome. However, lectins are largely inactivated by cooking and fermentation, and they do not pose a significant risk in a normal diet. In fact, lectins are being researched for use in cancer therapies.

Benefits of Soy


Arginine in soy has multiple benefits, including promoting the release of growth hormone, improving insulin sensitivity, and reducing the risk of cardiovascular diseases. The FDA recognizes that soy protein can reduce the risk of coronary heart disease.

Bone Strengthening

Isoflavones in soy can stimulate bone-forming cells, strengthening bones.


β-Conglycinin, a protein in soy, has been shown to reduce body fat and increase adiponectin, improving glucose tolerance. Studies have shown that 5 g of β-conglycinin per day can significantly reduce visceral fat.

Methionine Deficiency and Capillary Increase

Methionine deficiency in soy can promote fat breakdown and increase the number of capillaries in skeletal muscle. This can potentially enhance muscle growth and improve cardiovascular health.



While soy has several issues, it also offers numerous benefits. By understanding and addressing these issues, we can maximize the health benefits of soy. "Good grief... but now we see a way to defy fate!"


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