病患詢問. 吃糙米會貧血嗎?
節錄其中一段 "穀物的麩質含有較多的植酸, 植酸與鈣，鎂，鐵，銅和鋅具有很強的結合力，導致沉澱，因而降低礦物質吸收"
備註: 植酸可以降低心血管疾病風險. 但大量食用需注意是否發生礦物質缺乏美國疾管局網站介紹
Phytic acid—
a naturally occurring plant constituent that functions as the storage form of phosphorous for the germinating seed. It is an inositol phosphate consisting of a ring of six phosphate ester groups. It is expressed in milligrams in the database.
查詢鐵質的資訊.
臨床筆記有一篇整理的文章:
缺鐵性貧血. 食物中鐵的來源可以區分兩類
1. 血基質鐵（heme iron)(血紅素鐵), 人體較容易吸收
2. 非血基質鐵. 植物所含的鐵, 人體吸收率比上面的差20-30%
哈佛公共衛生學院的網站有一篇相關的. (可翻譯成抗營養素有害嗎?)
The Nutrition Source- Are Anti-Nutrients Harmful?下面是 google 中文翻譯
結論：抗營養素對人類長期健康的利弊是活躍的研究領域。儘管某些食物在加工和烹飪後可能含有殘留量的抗營養物質，但
食用這些食物對健康的益處超過了任何潛在的負面營養影響。每天吃多種營養食物，避免一頓吃大量單一食物，有助於抵消抗營養素造成的營養吸收的輕微損失。
「抗營養素」一詞顯示了它們的意義。營養素是滋養植物和動物生長和生存的物質，而抗營養素之所以被稱為抗營養素，是因為它們可以阻止營養素的吸收。抗營養素天然存在於動物和許多植物性食品中。在植物中，它們是旨在防止細菌感染和被昆蟲吃掉的化合物。 [1]
我們吃的食物中有幾種化合物被歸類為抗營養素。範例包括：
十字花科蔬菜（綠花椰菜、球芽甘藍、高麗菜、羽衣甘藍）中的芥子油苷和甲狀腺腫素可以阻止碘的吸收，這可能會幹擾甲狀腺功能並導致甲狀腺腫。那些已經患有碘缺乏症或患有甲狀腺功能減退症的人最容易受到影響。
豆類（豆類、花生、大豆）、全穀物中的凝集素會幹擾鈣、鐵、磷和鋅的吸收。
綠葉蔬菜、茶、豆類、堅果、甜菜中的草酸鹽可以與鈣結合並阻止吸收。
全穀物、種子、豆類和一些堅果中的
植酸鹽（植酸）會減少鐵、鋅、鎂和鈣的吸收。 [2,3]
豆類、全穀物中的皂苷會幹擾正常的營養吸收。
茶、咖啡、豆類中的單寧酸會降低鐵質的吸收。
目前尚不清楚我們的飲食中因抗營養物質而損失了多少營養物質，而且其影響因人而異，取決於個人的新陳代謝以及食物的烹飪和準備方式。許多抗營養物質，如植酸鹽、凝集素和芥子油苷，可以透過在食用前浸泡、發芽或煮沸食物來去除或失去活性。
另一個考慮因素是這些抗營養物質會影響同一餐中營養素的吸收。因此，為了降低這種風險，建議
避免在一餐中食用大量含有抗營養素的食物，並全天均衡飲食，多種食物。 [3]
例如，早餐不要吃兩杯加牛奶的麩皮麥片，而是選擇一杯加牛奶的麥片和一杯新鮮莓果。
患有與礦物質缺乏相關的疾病的高風險族群，例如缺鈣引起的骨質疏鬆症或缺鐵引起的貧血，可能希望監測他們選擇的食物中的抗營養成分。另一種策略可能是改變食用抗營養素食物的時間。例如，在兩餐之間喝茶而不是在吃飯時喝茶，以減少鐵吸收不良的機會，或者
在食用含有植酸鹽的高纖維麥麩穀物後幾小時服用鈣補充劑。
一些對吃富含抗營養物質的植物性食物的素食者的研究通常不會顯示鐵和鋅的缺乏，因此身體可能透過增加腸道中這些礦物質的吸收來適應抗營養物質的存在。 [3] 不過，其他研究表明，素食者的鐵儲備和血鋅水平通常低於非素食者。 [4] 非血紅素鐵（植物性食品中的形式）和鋅在體內的吸收程度受到植酸鹽等抑制劑含量的影響。一項綜述發現，這些抑制劑會對非血紅素鐵的吸收產生負面影響，影響範圍從 1% 到 23% 不等。 [4]
請記住，抗營養素也可能對健康有益。例如，植酸已被發現可以降低膽固醇、減緩消化並防止血糖急劇上升。 [2] 許多抗營養素具有抗氧化和抗癌作用，因此不建議完全避免使用它們。 [3,5,8]
The takeaway: The pros and cons of anti-nutrients on long-term human health is an area of active research. Though certain foods may contain residual amounts of anti-nutrients after processing and cooking, the health benefits of eating these foods outweigh any potential negative nutritional effects. Eating a variety of nutritious foods daily and avoiding eating large amounts of a single food at one meal can help to offset minor losses in nutrient absorption caused by anti-nutrients.
The term “anti-nutrients” suggests what they are. Whereas nutrients are substances that nourish plants and animals to grow and live, anti-nutrients earn their title because they can block the absorption of nutrients. Anti-nutrients are naturally found in animals and many plant-based foods. In plants, they are compounds designed to protect from bacterial infections and being eaten by insects. [1]
There are several compounds in the foods we eat classified as anti-nutrients. Examples include:
Glucosinolates and goitrogens in cruciferous vegetables (broccoli, Brussels sprouts, cabbage, kale)—can prevent the absorption of iodine, which may then interfere with thyroid function and cause goiter. Those already with an iodine deficiency or a condition called hypothyroidism are most susceptible.
Lectins in legumes (beans, peanuts, soybeans), whole grains—can interfere with the absorption of calcium, iron, phosphorus, and zinc.
Oxalates in green leafy vegetables, tea, beans, nuts, beets—can bind to calcium and prevent it from being absorbed.
Phytates (phytic acid) in whole grains, seeds, legumes, some nuts—can decrease the absorption of iron, zinc, magnesium, and calcium. [2,3]
Saponins in legumes, whole grains—can interfere with normal nutrient absorption.
Tannins in tea, coffee, legumes—can decrease iron absorption.
It is not known how much nutrient loss occurs in our diets because of anti-nutrients, and the effects vary among individuals based on their metabolism and how the food is cooked and prepared. Many anti-nutrients like phytates, lectins, and glucosinolates can be removed or deactivated by soaking, sprouting, or boiling the food before eating.
Another consideration is that these anti-nutrients affect the absorption of nutrients eaten at the same meal. Therefore to lower this risk, it is recommended to avoid eating large quantities of foods containing anti-nutrients at one meal, and to eat a balanced diet throughout the day with a variety of foods. [3] For example, instead of eating two cups of bran cereal with milk for breakfast, choose one cup of cereal with milk and one cup of fresh berries.
People who are at high risk for diseases related to mineral deficiencies, such as osteoporosis with calcium deficiency or anemia with iron deficiency, may wish to monitor their food choices for anti-nutrient content. Another strategy could be altering the timing of eating foods with anti-nutrients. Examples are to drink tea between meals instead of with a meal to reduce the chances of iron being poorly absorbed, or taking a calcium supplement a few hours after eating a high-fiber wheat bran cereal that contains phytates.
Some studies on vegetarians who eat diets high in plant foods containing anti-nutrients do not generally show deficiencies in iron and zinc, so the body may be adapting to the presence of anti-nutrients by increasing the absorption of these minerals in the gut. [3] Still, other studies have shown that iron stores and blood zinc levels in vegetarians are typically below those of non-vegetarians. [4] How well non-heme iron (the form found in plant foods) and zinc are absorbed in the body is impacted by the amount of inhibitors such as phytates. A review found that these inhibitors negatively affected the absorption of non-heme iron, varying from 1% to 23%. [4]
Keep in mind that anti-nutrients may also exert health benefits. Phytates, for example, have been found to lower cholesterol, slow digestion, and prevent sharp rises in blood sugar. [2] Many anti-nutrients have antioxidant and anticancer actions, so avoiding them entirely is not recommended. [3,5,8]
