MCQ Detailed View

Vitamin B7, also known as Biotin, is a water-soluble vitamin that plays a vital role in many biological processes. It is part of the B-complex vitamin family and is essential for the metabolism of carbohydrates, fats, and proteins. Biotin acts as a coenzyme in carboxylation reactions, which help the body convert nutrients into energy.

One of the most recognizable symptoms of biotin deficiency is hair loss (alopecia). Without sufficient biotin, the body struggles to maintain healthy hair, skin, and nails. This is why biotin is often called the "beauty vitamin" and is commonly included in hair and nail supplements.

Other possible signs of biotin deficiency include brittle nails, skin rashes (especially around the eyes, mouth, and nose), fatigue, depression, and neurological symptoms such as tingling in the hands and feet. However, among the options given in this question, hair loss is the key and most direct symptom.

It is important to note the difference between symptoms of deficiencies of other vitamins:

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  Pellagra is caused by a deficiency of Vitamin B3 (Niacin).

  
  


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  Xerophthalmia results from Vitamin A deficiency.

  
  


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  Muscle weakness can occur in many conditions but is more associated with deficiencies of minerals like potassium or vitamins such as D.

  
  

Biotin deficiency is rare because the vitamin is widely available in foods like eggs, nuts, seeds, and whole grains, and it is also produced in small amounts by gut bacteria. However, it can occur in individuals who consume large amounts of raw egg whites (due to a protein called avidin, which binds to biotin and prevents absorption) or in people with certain genetic or medical conditions.

In conclusion, the most well-known symptom of Vitamin B7 deficiency is hair loss, making it the correct answer.