Those are also symptoms of a deficiency of B-12, a key nutrient needed to make red blood cells and DNA and keep the nervous system working right.

这也是维生素b - 12缺乏的症状，B - 12是合成红细胞和DNA、维持神经系统正常运转的不可或缺的营养物质。

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Deficiency disease a disease caused by deficiency of a particular essential nutrient (such as a MICRONUTRIENT or trace element), usually with a characteristic set of symptoms.

由于缺乏一种特殊的必要营养物质(微量营养素或微量元素)而导致的疾病，通常表现出具有特征性的一系列症状。

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Some have more serious symptoms such as bowel mal-absorption, abdominal pain, diarrhea and nutrient or vitamin deficiency.

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