tongue soreness, and other symptoms may occur with vitamin B12 deficiency, but none of these signs alone proves that a person is deficient.
The best way to determine whether vitamin B12 is actually low is through appropriate medical evaluation and, when necessary, blood testing.
If a deficiency is confirmed, treatment is usually effective, especially when it is identified early.
The most important approach is to maintain a balanced diet, understand your individual risk factors, and seek professional advice when persistent or unusual symptoms appear.