大豆
Soy
人类食用大豆的历史已有五千多年，大豆不仅不含胆固醇，其所含的丰富营养对人体更是非常有益，例如：蛋白质、必需氨基酸、碳水化合物以及维生素，并且高纤维、低饱和脂肪以及富含钙、铁、磷等矿物质。大豆还含有多样化的植物营养素、抗氧化剂及多醣体等有助于抵抗疾病的营养。自古以来，大豆因为其独特的性质备受推崇，并且被称为 “黄宝石”。
Soybeans have been part of the human diet for around 5,000 years. Not only is soy cholesterol free, but it also has all the nutrients essential for good health: protein, essential amino acids, carbohydrates, and vitamins. It is high in fiber, low in saturated fat, and rich in minerals like calcium, iron, and phosphorus. It is also packed with disease-fighting nutrients like phytochemicals, antioxidants, and polysaccharides. Soy has been called the "yellow jewel" since ancient times due to its unique characteristics.
最丰富的植物性蛋白质来源之一
One of the Most Abundant Sources of Plant Protein
不同于大多数植物性食物，大豆富含蛋白质。它由 36% 至 56% 的蛋白质组成，是最丰富的植物性蛋白质来源之一。而更为独特的是，大豆蛋白质还能如动物性蛋白质一般，为人体提供所有必需氨基酸。
Soy is rich in protein, unlike many plant foods. Made up of 36%-56% protein, soy is one of the most abundant plant sources of dietary protein. Like animal protein, soy protein is complete in that it provides all the essential amino acids needed for human health.
根据研究，过量的无法被消化的蛋白质容易沉积在人体内，进而可能引起过敏；过量的动物性蛋白质也会导致人体内的钙从尿液中流失，从而增加罹患骨质疏松症的风险。因此，不妨以大豆蛋白质作为日常饮食中摄取蛋白质的优先选择。
Studies indicate that excess undigested protein may cause allergies. In addition, diets high in animal protein cause excretion of calcium through urine and heighten the risk of osteoporosis. Therefore, soy protein is an ideal source of protein in one's daily diet.
此外，大豆蛋白质所含的氨基酸种类齐全，尤其富含赖氨酸，正好补充了大多数谷物赖氨酸不足的缺陷。因此，无论是对于关注健康的人士，还是素食主义者，抑或是想要透过低卡路里饮食来控制体重者，大豆都是补充蛋白质的绝好选择。
Soy protein has a complete range of amino acids, especially lysine, which is lacking in most grains. Hence, soy is an ideal choice of protein for health-conscious people, vegetarians, and those managing their weight with low-calorie diets.
优质的植物性雌激素来源
Excellent Source of Phytoestrogens
大豆含有天然的植物性雌激素，主要包括异黄酮以及木酚等。它们集中在一起后，雌激素效用明显。异黄酮对健康非常重要，大豆也是目前为止已知的最重要、最优质的异黄酮来源。
Soy contains natural phytoestrogens, mainly isoflavones and lignans. Their estrogenic effects are obvious when these natural phytoestrogens are concentrated together. Isoflavones are very important to good health. To date, soy is the most important and best-known source of isoflavones..
有些人认为，大豆所含有的植物性雌激素可能会导致一些由荷尔蒙诱发的癌症，如：乳癌、子宫内膜癌和前列腺癌。然而事实刚好相反，植物性雌激素能够帮助预防癌症。
Some people believe that the phytoestrogens found in soy may cause hormone-related cancers, such as breast cancer, endometrial cancer, and prostate cancer. In actuality, phytoestrogens help to prevent cancer.
大豆异黄酮同时肩负着雌激素与抗雌激素的两种职能。一种理论表示，对于体内荷尔蒙值较高的更年前期女性，大豆中的植物性雌激素会发挥抗雌激素的作用，透过抑制雌激素的某些功能，来预防一些由荷尔蒙引起的癌症。
Soy isoflavones exert both estrogenic and anti-estrogenic effects. One theory is that phytoestrogens may act as anti-estrogens in premenopausal women who tend to have higher hormone levels. Phytoestrogens may block some effects of estrogen and thus protect against hormone-related cancers.
大豆中的植物性雌激素能抢先与细胞的雌激素受体结合，阻止容易引发癌症的雌激素与受体结合，从而阻止癌细胞的生长、抑制肿瘤，降低罹患乳癌等雌激素依赖型癌症的风险。
Phytoestrogens fill estrogen receptor sites on cells, keeping cancer-causing estrogen from promoting the growth of malignant cells. Therefore, phytoestrogens from plant foods may lower the risk of estrogen-dependent cancers, such as breast cancer.
新加坡国立大学、美国南加州大学和明尼苏达大学的研究显示，新加坡华裔女性定期食用豆奶等大豆制品，可以降低 18% 罹患乳癌的风险。这项由约 35,000 名华裔女性参与的为期十年的研究，其研究结果发表于 2008 年的《英国癌症期刊》上。
According to a study by the National University of Singapore, the University of Southern California, and the University of Minnesota, Singapore Chinese women who regularly consumed soy products such as soy milk had a significant 18% reduction in breast cancer risk. This study tracked about 35,000 Chinese women over 10 years and was published in the British Journal of Cancer in 2008.
2008 年 10 月发表在《国际癌症期刊》上的另一项研究中，日本研究者发现大量食用大豆食品可以显著降低罹患雌激素受体阳性肿瘤和人类表皮生长因子阴性肿瘤的风险。
In another study, published in the International Journal of Cancer in October 2008, Japanese researchers found that high levels of soy food consumption appeared to specifically reduce the risk of estrogen receptor (ER)-positive tumors and human epidermal growth factor receptor 2 (HER2)-negative tumors..
极易被人体吸收的钙质与铁质来源
Easily Absorbed Source of Calcium and Iron
钙和铁是促进骨骼健康、制造血液中的血红素 (运送氧分子的主要物质) 不可或缺的重要矿物质。大豆和其他所有的豆类一样，富含钙质和铁质。100 克煮熟的大豆含有 145 毫克的钙和 2.5 毫克的铁，且极易为人体吸收。大豆也富含铁蛋白，一种能够储存铁同时能控制身体释放铁的蛋白质。根据美国一项针对 18 位极度缺铁的女性进行的研究发现，食用大豆汤和由大豆粉制成松饼的女性，28 天后体内红血球的铁吸收量增加了27%。
Iron and calcium are minerals the body needs to keep bones healthy and to produce hemoglobin in the blood. Hemoglobin plays a key role in transporting oxygen in the body. Soy, like all legumes, is a good source of calcium and iron. Just 100 g of boiled soybeans contain 145 mg of calcium and 2.5 mg of iron that are easily absorbed by the body. In addition, soy contains ferritin, a protein that stores iron and releases it in a controlled fashion. U.S. researchers studied 18 women, most of whom had marginal iron deficiency. They were given soybean soup and muffins made with soy flour. After 28 days, the researchers found there was a 27% increase of iron absorption in the women's red blood cells.
此外，大豆含有一种称为果寡糖 (F05) 的物质，能够增加肠道内有益菌的比例。研究证实，FOS 能增加比菲德氏菌的繁殖，这种菌类可促进人体对钙和镁的吸收，进而减低罹患骨质疏松症的风险。
Moreover, soy contains fructooligosaccharides (FOS), which can increase the amount of good bacteria in the intestines. Research has also shown that FOS can increase the multiplication of Bifidobacterium bifidum (B.bifidum), which helps promote the absorption of calcium and magnesiumand further reduces the risk of osteoporosis..
提升免疫力
Immunity-enhancing Effects
在一项发表于《Tumori 期刊》的研究中，研究人员对老鼠投予会抑制细胞及体液免疫力的致癌物二丁胺 (Dibutylamine) 及硝酸钠 (Sodium nitrite)，然后再喂食大豆，结果显示并无肿瘤形成，证实大豆能改善细胞及体液的免疫力，从而提升免疫机能。
In a study published in Tumori, rats were given the carcinogens dibutylamine and sodium nitrite, which resulted in depressed cellular and humoral immunity. Soybean was then administered. Results indicated an absence of tumor growth, demonstrating that soybean has the ability to increase immune function by enhancing both cellular and humoral immunity.
强大的抗癌功效
Strong Anticancer Effects
大豆中的肌醇六磷酸 (一类植酸盐) 具有预防结肠癌的功效。研究指出，大豆所含的大豆皂苷能抑制肿瘤细胞的生长。此外，大豆中所含有的主要异黄酮：染料木黄酮、大豆苷元和黄豆黄素，更是有抗癌功效。异黄酮能作为一种抗氧化剂，在自由基造成 DNA 突变为癌细胞之前就将之毁灭。
Phytates (the salts of phytic acid) in soy have been associated with reduced colon cancer risk. Research shows that soy saponins help to inhibit cancer cell growth. Furthermore, the main isoflavones in soy-genistein, daidzein, and glycitein-have anticancer effects. Isoflavones also work as antioxidants, destroying free radicals before they cause cells to mutate into cancer..
染料木黄酮
Genistein
染料木黄酮 (Genistein) 可以预防和治疗前列腺癌和乳癌。研究证实它能有效抑制癌细胞的成长和扩散，美国的国家癌症研究所即视其为一种抗癌药物来进行测试。
Genistein has shown promise in preventing and treating prostate and breast cancers. Research shows that genistein can effectively inhibit the growth and spread of cancer cells. As such, the U.S. National Cancer Institute is studying the possibility of using genistein as an anticancer drug.
一项为期十年的大型研究显示，血液中含有大量染料木黄酮的女性患上乳癌的风险较低。在一项超过 24,000 位日本中老年女性参与的研究中发现，摄取最多量染料木黄酮的受试者比起摄取最少量染料木黄酮的受试者，罹患乳癌的风险低 65%。这项研究仅测量了受试女性血液中染料木黄酮的数值，而没有询问她们的饮食。学者们认为染料木黄酮可以和乳房细胞的雌激素受体结合，并抑制雌激素的致癌功能，从而降低罹患乳癌的风险。
A large study spanning 10 years suggests that women with high blood levels of genistein seem to have a lower risk of developing breast cancer. Among more than 24,000 middle-aged and older Japanese women, those with the highest blood levels of genistein were about 65% less likely to develop breast cancer compared to those with the lowest blood levels of genistein. This study is unique because the researchers measured blood levels of genistein instead of asking what the women ate. The researchers theorize that genistein may lower breast cancer risk by sitting in the estrogen receptors on breast cells and blocking the cancer-promoting effects of estrogen made by the body.
大豆苷元
Daidzein
大豆苷元 (Daidzein) 能预防荷尔蒙敏感性的癌症，如乳癌、子宫内膜癌以及前列腺癌等；在配合某些预防剂或者疗法使用时，大豆苷元特别能发挥功效。例如：三苯氧胺是有效预防雌激素受体阳性乳癌的化学预防剂。然而，长期使用三苯氧胺会明显增加罹患子宫内膜癌 (始发于子宫的癌症) 的机率。欧洲塞浦路斯大学的实验研究显示，大豆苷元可以降低三苯氧胺诱发子宫内膜癌的风险。
Daidzein may prevent hormone-sensitive cancers like breast cancer, endometrial cancer, and prostate cancer. It could be especially useful when used in tandem with other preventives and treatments. For instance, tamoxifen is an effective chemopreventive agent against ER-positive breast cancer. However, long-term use of tamoxifen may significantly increase the risk of endometrial cancer, which begins in the uterus. An experimental model by the University of Cyprus suggests that daidzein may lower the increased risk of endometrial cancer produced by tamoxifen.
黄豆黄素
Glycitein
黄豆黄素 (Glycitein) 只占大豆异黄酮的 5% 至 10%，具有微弱的雌激素作用。它也具有抗氧化功能，可以预防癌症、骨质疏松症和动脉内斑块的形成。
Glycitein accounts for 5%-10% of the isoflavones in soy foods. Studies found it to have weak estrogenic activity. It may also have antioxidant activities and help prevent cancer, osteoporosis, and the formation of plaque inside the arteries.
预防心血管疾病
Cardiovascular Disease Prevention
大豆不含胆固醇。大豆异黄酮可以发挥较弱的雌激素功效，有助于降低低密度脂蛋白胆固醇 (“坏”胆固醇)，同时增加高密度脂蛋白胆固醇 (“好”胆固醇)，从而促进心脏健康。大豆皂苷有助于降低胆固醇，并促进胆汁的排泄。
Soy contains no cholesterol. Soy isoflavones have weak estrogenic effects that help lower low-density lipoprotein ("bad") cholesterol and increase high-density lipoprotein ("good") cholesterol, thereby promoting heart health. Soy saponins help lower cholesterol by increasing bile excretion.
美国食品与药物管理局 (FDA) 的研究即指出，每天以低饱和脂肪、低胆固醇的饮食为主，再配合食用 25 克大豆蛋白质，能够帮助降低血液中的胆固醇，从而减少罹患心血管疾病的风险。
The U.S. Food and Drug Administration (FDA) has concluded that 25 g of soy protein a day, as part of a diet low in saturated fat and cholesterol, may help to lower blood cholesterol levels, thereby lowering the risk of heart disease.
此外,研究发现,饮食中的钠摄入量过高而钾摄入量过低即可能引发高血压和动脉硬化,从而导致中风。而大豆中含有丰富的钾,能够帮助身体去除多余的钠,进而帮助降低中风的机率。另有研究显示,大豆中的不饱和脂肪酸能降低胆固醇含量,预防动脉硬化、降低脂肪在血管壁上的囤积,从而可以帮助降低中风的风险。
Research shows that an unhealthy diet high in sodium and low in potassium may lead to high blood pressure and atherosclerosis, both of which are main risk factors of stroke. Soy is rich in potassium, which helps the body to get rid of excess sodium, thus lowering the risk of stroke. Other research indicates that unsaturated fatty acids found in soybeans may help to lower cholesterol levels, prevent atherosclerosis, and decrease the accumulation of fats on arterial walls, thus helping to reduce the risk of stroke.
大豆中高量的植物固醇亦具有降低胆固醇的功效。大豆中含量最多的植物固醇是谷甾醇 (Sitosterol，占 60%)，其次是菜油甾醇 (Campesterol，占 20%) 和豆甾醇 (Stigmasterol，占 20%)。谷甾醇已被用来治疗高胆固醇血症 (血液中的胆固醇含量非常高的症状)。临床研究更指出，摄取植物固醇可以降低体内 10% 的胆固醇总量、15% 低密度脂蛋白胆固醇的含量。
The high amounts of phytosterols in soy have the ability to lower cholesterol. Sitosterol makes up the largest proportion of phytosterols in soy (60%), followed by campesterol (20%) and stigmasterol (20%). Sitosterol has been used to treat hypercholesterolemia (very high levels of cholesterol in the blood). In addition, clinical studies have shown that phytosterol intake can reduce total cholesterol by 10% and LDL cholesterol by 15%.
植物固醇能够减少身体对胆固醇的吸收。研究显示，每天摄入 1.5 至 1.8 克的植物固醇，可将胆固醇的吸收降低 30% 至 40%；若每天摄入 2.2 克植物固醇，则胆固醇的吸收可降低 60%，进而降低罹患心血管疾病的机率。
Phytosterols can lower the body's absorption of cholesterol. Research shows that consuming 1.5-1.8 g of phytosterols a day can reduce cholesterol absorption by 30% -40%, while an intake of 2.2 g of phytosterols per day can reduce cholesterol absorption by 60%, thereby lowering the risk of cardiovascular disease.
预防糖尿病
Diabetes Prevention
大豆的升糖指数非常低 (仅 10-23)，它只会引起血糖和胰岛素的小波动，这意味着它可以帮助稳定血糖值。食物的升糖指数 (Glycemic Index) 指含碳水化合物的食物在两小时内使血糖升高的能力，用 0 到 100 的数值表示。
The glycemic index of soybean is 10-23, which is very low. It will cause only small fluctuations in blood glucose and insulin levels, helping to keep the blood sugar levels more stable. The glycemic index indicates the ability of carbohydrate-containing foods to raise blood glucose levels within two hours, on a scale of 0-100.
糖尿病患者罹患心血管疾病的危险是一般人的 2 至 4 倍。美国糖尿病协会 (American Diabetes Association) 即建议糖尿病患者以大豆作为摄取蛋白质的来源。一项英国的研究显示，大豆中的蛋白质和异黄酮有助于控制血糖，对患有 2-型糖尿病的更年后期女性有帮助，能改善她们的身体对胰岛素的敏感性，降低引发诸如心脏病、肾脏病等糖尿病并发症的机率。
Diabetics are two to four times more likely to develop cardiovascular disease than people without diabetes. The American Diabetes Association recommends soy protein for diabetics. Research conducted in the UK showed how soy protein and soy isoflavones can aid in controlling blood sugar, helping postmenopausal women with type 2 diabetes become more sensitive to insulin, and reducing the risk of diabetes-related complications, such as heart disease and kidney damage.
此外，大豆是可溶性纤维很好的来源之一。可溶性纤维有助于控制血糖，因而减缓身体对糖分的吸收。
In addition, soy is a good source of soluble fiber. Soluble fiber may help improve blood sugar control because it slows down the rate at which the body absorbs sugar.
预防肾脏病
Kidney Disease Prevention
大豆富含的植物性蛋白质不会对肾脏造成负担，因此能够降低肾脏受损的风险。研究显示大豆蛋白质较动物性蛋白质在帮助肾功能方面更有效果。
Soy protein will not overburden the kidneys, hence reducing the risk of kidney damage. Studies have shown that soy protein is significantly better at aiding kidney function than animal protein.
肾脏病患也需要限制磷的摄取量。肾脏受损的症状之一是高磷血症，会影响身体的钙质平衡。虽然大豆含有大量的磷，却是以植酸盐的形式存在，所以不会被大量吸收。
Those with kidney disease must restrict their phosphorus intake. A result of damaged kidneys is hyperphosphatemia, or a high level of phosphate in the blood. This interferes with calcium balance in the body. Although soybeans contain large amounts of phosphorus, it is in the form of phytate, which is poorly absorbed.
预防骨质疏松症
Osteoporosis Prevention
中老年女性因为雌激素水平的下降容易患上骨质疏松症。在美国，由骨质疏松症导致的髋部骨折是更年期女性容易罹患的疾病之一。调查发现，更年期的美国女性罹患髋部骨折的人数大约是日本女性的两倍，研究认为这与日本女性经常食用大豆食品有关。
Middle-aged and elderly women are at higher risk of osteoporosis due to declining estrogen levels. One main condition experienced by menopausal women in the U.S. is hip fracture caused by osteoporosis. The rate of hip fractures caused by osteoporosis in menopausal American women is nearly double that of Japanese women. Research has shown that this may be due to the latter's regular consumption of soy foods.
研究指出，大豆的异黄酮 (如：染料木黄酮) 内所含的植物性雌激素可改善肠内钙质的吸收，同时促进腰脊柱的骨质更新，并且能提高骨细胞的活性，进而减少骨质流失、增加人体对钙的吸收、增加骨质密度，有助于预防骨质疏松症和增进骨骼健康。
Scientists discovered that soy isoflavones can help increase the absorption of calcium in the intestines, promote bone renewal in the lumbar spine, and minimize bone loss while enhancing bone cell growth. This, in turn, enhances the body's calcium absorption and increases bone density, helping to prevent osteoporosis and maintain bone health.
控制体重
Weight Management
正在控制体重的人，往往其日常饮食会选择以低卡路里饮食为主，此时，充足的蛋白质摄取量就显得非常重要，因为充足的蛋白质可以预防肌肉量的减少。由于肌肉消耗的卡路里比脂肪多，所以肌肉越多，新陈代谢率就越高。而当选择低卡路里饮食时，若不摄取充足的蛋白质来合成或维持肌肉，会导致肌肉不足而无法继续消耗卡路里。大豆富含高量的植物性蛋白质,，无疑是体重控制者的理想选择。
People seeking to manage their weight will usually follow a low-calorie diet. Adequate protein intake is very important when on a low-calorie diet because it helps prevent muscle loss. Muscle burns more calories than fat does. The more muscle a person has in relation to fat, the higher his or her metabolic rate will be. When on a low-calorie diet, not eating enough to build or maintain muscles will result in less muscle available to continue to burn calories. High in plant protein, soy is undoubtedly the ideal source of protein for people managing their weight.
另一方面，大豆中的多胜肽 (Polypeptide) 和其他成分能够帮助减轻体重。科学家认为，大豆中活跃的多胜肽能帮助加速脂肪分解的过程。研究显示大豆能促进新陈代谢，帮助减轻体重。同时，大豆胜肽能把饱足的讯息传达给大脑，并延长食物离开肠胃的时间。
Polypeptides and other compounds of soy also help weight loss in other ways. Scientists think that an active polypeptide in soy helps speed up the fat decomposition process. Experimental studies have shown that soy may aid weight loss by boosting metabolism. At the same time, soy peptides may interact with receptors in the brain to signal a feeling of satiety while delaying emptying of the stomach..
此外，大豆中的膳食纤维也可使人体长时间产生饱足感，进而减少对其他食物的摄取。大豆更具有低热量和低脂肪的优点。
Moreover, the dietary fiber in soybeans allows one to feel full longer, which reduces the intake of other foods. Soy is also low in calories and fat.
维持荷尔蒙平衡
Hormone Balance
大豆中的异黄酮和其他植物性雌激素可以模仿女性荷尔蒙的功能，帮助调节人体内过高或过低的雌激素，使其保持在正常数值。
Isoflavones and other phytoestrogens in soy can mimic the effects of the female hormone estrogen and help to prevent the body's estrogen level from being too high or low, keeping it at a normal level.
因此大豆有助于美容护肤、缓解经期不适、延缓更年期和老化、预防因雌激素失调所引起的疾病 (如：乳癌、子宫内膜癌、前列腺癌) 等。对于更年后期的女性，大豆中的植物性雌激素则会发挥雌激素的作用，舒缓如热潮红、燥热等更年期症状。
Because of this effect, soy helps to improve complexion, alleviate menstrual discomfort, delay the onset of menopause and visible signs of aging, and may prevent diseases caused by hormonal imbalances, like breast, endometrial, and prostate cancers. For postmenopausal women, phytoestrogens in soy act like estrogens, thus relieving symptoms of menopause, such as hot flashes and increases in body temperature.
助益大脑活动
Brain Activity Enhancement
磷脂对大脑健康非常重要。大豆富含磷脂 (尤其是卵磷脂)，研究指出在饮食中多摄取大豆有助于提高记忆力与学习能力，也有助于增加活力。
Phospholipids are crucial to brain health. Soy is rich in phospholipids, specifically lecithin, hence a diet high in soy contributes to better learning capabilities and helps to improve memory and vitality.
抗血栓
Blood Clot Prevention
研究发现，大豆中的大豆皂苷可以调控血小板减少和凝血酶 (促进生成血栓的物质) 的形成，因而具有抗血栓的作用。
Research has found that the soyasaponin in soy helps control blood platelets from lessening and thrombin, a key clot promoter, from forming, effectively preventing blood clots.
改善肤质
Complexion Improvement
研究发现，豆酱中含有一种亚油酸，能够抑制过量黑色素 (造成色斑的主要因素) 的合成。同时能使皮肤恢复弹性和光滑柔嫩，并具美白功效。
Research shows that soybean paste contains linoleic acid, which helps suppress the formation of excess melanin, which is the main cause of pigmentation. At the same time, it helps promote softer, smoother, and fairer skin.
题外话: 别误会大豆了！
Did You Know? Soy Myths
近期，坊间有人会因为大豆中所含的植酸与嘌呤对大豆产生担忧与误解，认为食用大豆会带来健康负担。其实不然，众多科学研究早已证实食用大豆是安全有益的。
Recently, there were concerns that soy might burden health because it contains phytic acid and purine. These are unfounded, as many studies have proven that soy consumption is safe and beneficial to health..
大豆与植酸
Soy and phytic acid
大豆含有植酸 (或称为肌醇六磷酸) 一 一种有机酸，广泛存在于谷物的外壳和种子中。由于其独特的结构，植酸容易结合钙、铁、镁、磷等元素，尤其容易结合肠胃道内的锌元素。因此有人认为长期食用豆制品的人体容易缺乏微量元素；并且建议缺锌的人最好不要食用如豆浆等豆制品。
Soy contains moderate amounts of phytic acid, a natural organic acid present in the hulls of grains and seeds. Its unique structure enables it to bind easily to elements like calcium, iron, magnesium, phosphorus, and, in particular, zinc in the gastrointestinal tract. Hence, some people think that long-term consumption of soy products will cause a deficiency of trace elements in the human body and suggest that those with zinc deficiency avoid soy products such as soy milk.
其实，大豆本身含有丰富、极易被人体吸收的钙质和铁质，以及果寡糖 (FOS) 一 能够促进人体对钙和镁的吸收，从而能够极大地弥补植酸所结台的微量元素。此外，大豆透过发酵，如制成豆腐乳、豆豉、纳豆等，也能改善植酸问题；发酵过程中，微生物分解了大豆中的植酸，使得其中所含的钙、铁、锌等矿物质更容易被人体吸收。
In actuality, soy is rich in iron and calcium that are easily absorbed by the human body. It is also rich in FOS, which can promote absorption of calcium and magnesium, thereby making up for the metallic elements bound to phytic acid. In addition, fermented soy (such as preserved bean curd, preserved soybeans, and natto) can also alleviate the phytic acid problem. During fermentation, microorganisms break down the phytic acid in soy so that minerals present in soy like calcium, iron, and zinc can be more easily absorbed by the human body.
因此只要适量食用，或是选择适合自己的豆制品，再加上均衡的膳食，大豆中的植酸并不会对人体吸收矿物元素造成很大的影响。其实，植酸还因其抗癌功效对健康有利。若对大豆中的植酸心存顾虑，也可将大豆浸泡后去除外皮，以降低其中的植酸含量。
Hence, phytic acid in soy will not have a major effect on mineral absorption when individuals consume moderate or suitable amounts of soy products as part of a balanced diet. In fact, phytic acid benefits health with its anticancer effects. To reduce the amount of phytic acid, soak soybeans before removing their skin.
大豆与嘌呤
Soy and purine
痛风是困扰很多人的疾病，特别常见于40岁以上的男性和更年期的女性。嘌呤是人体内的一种有机化合物，是构成 DNA 和 RNA 的主要成分，对能量供应、代谢调节及辅酶的组成等都十分重要。
Gout commonly affects men over 40 years old and menopausal women. It is a disorder of purine metabolism. Purine is an organic compound that occurs naturally in the human body. It is the main component of DNA and RNA and is essential for providing energy, regulating metabolism, and forming coenzymes.
然而由于人体细胞的老化，或是过度食用动物内脏、海鲜等高嘌呤食物，都会导致人体内嘌呤含量过高；这些嘌呤进一步分解生成尿酸，如果过量的尿酸来不及排泄或者尿酸的排泄机制退化，就会使血液中尿酸浓度升高，进而形成晶体沉积在关节、组织和肾脏中；人体的免疫系统会对这些晶体发动攻击，因为它们并不属于人体的关节、组织或肾脏。免疫系统的这种反应会引发炎症，进而诱发痛风。
Aging body cells or excessive consumption of purine-rich foods such as organ meats and seafood can lead to excessive amounts of purine in the body. Uric acid is produced when the body breaks down purines. If the body cannot remove excess uric acid in time or the uric acid excretion mechanism degenerates, there will be high levels of uric acid in the blood. This can cause painful uric acid crystals to form in joints, tissues, and kidneys, causing the immune system to mount an attack against these crystals because they do not belong there. This immune reaction causes inflammation and induces gout.
近期坊间流传，大豆及豆制品中富含嘌呤，尤其豆浆，因嘌呤的亲水性，导致大豆在磨成豆浆后嘌呤含量又多出好几倍；因此，痛风病人应少吃大豆及豆制品。其实不然。大豆的嘌呤含量适中，低于高嘌呤食物 (如动物内脏)，却高于低嘌吟食物 (如水果和蔬菜)。
A myth is circulating that gout patients should avoid soybeans and soy products, especially soy milk, because they are rich in purine, which is highly hydrophilic and increases greatly after soybeans are ground into soy milk. That is not true. The amount of purine in soy is moderate; it is lower than purine-rich foods (e.g., organ meats) but higher than foods low in purine (e.g., fruits and vegetables).
而许多豆制品，如豆腐，在加工过程中要挤去多余的水分，多数嘌呤会随水分流走。再如豆浆，一斤大豆可以做成五斤豆浆，因此每斤豆浆的嘌呤含量其实很低。一项日本的研究指出，豆腐对血尿酸浓度的影响很小并且短暂，对痛风病人来说是一种安全的蛋白质补充食物。而一项历经 12 年超过 4 万 5 千名男性参与的研究，结论也显示：大量食用肉类和海鲜容易导致痛风，而适当食用高嘌呤的植物性食物并不会增加罹患痛风的风险。
Most purines are removed along with excess water during the manufacturing process of many soy products. Five hundred grams of soybeans can produce 2,500 ml of soy milk. Hence the amount of purines in 500 ml of soy milk is insignificant. A study by Japanese researchers concluded that tofu is a safe source of protein for gout patients due to its small and transient effect on plasma urate levels. A 12-year study involving more than 45,000 men found that higher levels of meat and seafood consumption are associated with an increased risk of gout, whereas moderate intake of purine-rich vegetables is not associated with an increased risk of gout.
此外，雌激素对尿酸的形成有抑制作用。大豆异黄酮可以平衡男性由于雄性激素的干扰引起的尿酸排泄异常，也可以补充更年期女性体内的雌激素，从而降低痛风的发病率。因此相比起大鱼大肉、鱼贝虾蟹，大豆及豆制品不仅老少咸宜，更是补充身体蛋白质安全理想的来源。
In addition, estrogens help inhibit the formation of uric acid. Soy isoflavones can restore balance to men experiencing irregularities in uric acid elimination due to interference from male hormones and replenish estrogens in menopausal women, thereby reducing gout incidence. Compared to fish, meat, seafood, and freshwater delicacies, soy and soy products are relatively safer and more ideal sources of protein.
资料来源：营养 免疫 长寿，免疫学家陈昭妃著
Source: Nutrition Immunity Longevity, Jau-Fei Chen, PhD, Immunologist