Brief Answer:
Needs to be investigated &treated specifically.

Detailed Answer:
Hi Spirit 888,
Thank you for the query. I understand your concern.
* The lesion you are describing in your throat.... could be due bad oral hygiene /streptococcal throat,/ yeast infection /or mono throat or kissing throat disease.
Can be confirmed by investigations( like anti streptolysin...ASO test / throat culture./biopsy as per need)
* The conditions indicate less immunity
- uncontrolled or long standing diabetes,
- treatment with antibiotics or steroids... which disturb normal protective oral bacteria & allow pathogens to be active
-HIV infection
-cancer
*Most of the times there are enlarged lymph glands in neck(may get painful &associated with fever in active phase of infection)
You do not mention of any pain or fever... so it's more likely to be chronic form of infection or bad oral hygiene.
* Any of the problems present lead to loss of weight due To less intake of food or less appetite or digestion leading to mal nutrition..
*Self care consists of a good oral hygiene along with regular warm water saline gargles, vappor inhalation to clear nasal passage . Drink plenty of clean warm water & healthy food(that you are already taking) with rich suply of proteins,vitamins A,B,C&E..
Sufficient salads.vegitables &fruits with ample of water would prevent possible constipation...that can hamper oral health.
Cleaning of palate (roof of mouth)& application of boro glycerine would help prevention of recurrent sore in mouth.
*In his context I would suggest a through ENT examination along with investigations to pin point the basic cause as well as find/exclude the factors leading to reduced immunity.
* A sufficiently long therapy with cause specific medication would get you free from the symptom
* please consult an ENT surgeon.
I hope that helps you.Anyfollow upquery is most welcome.
Thanks.

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