How can I tell which vitamins I'm lacking?

Deficiency in Vitamin A:

Deep white lines on nails, dry hair, rough skin, memory loss, irritability, and insomnia. Deficiency in Vitamin B1:

Hypersensitivity to sound, intermittent soreness in the calves. Deficiency in Vitamin B2:

Cracks and sores at the corners of the mouth, various skin diseases, a burning sensation in the hands and feet, and oversensitivity to light. Deficiency in Vitamin B3:

Swollen tongue, bad breath, mouth ulcers, and depression. Deficiency in Vitamin B6:

Thick tongue coating, swollen lips, dandruff, and dry oral mucosa. Deficiency in Vitamin B12:

Poor balance, intermittent pain in various parts of the body, and soreness in the fingers and toes. Deficiency in Vitamin C:

Poor wound healing, weakness, bleeding gums, and a thick tongue coating.

If you experience any of the above symptoms, especially middle-aged and older people, it is best to consult a doctor and not take vitamins on your own.

Improper doses of vitamins can be harmful to the body.

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