Welcome & thanks for posting your query to HCM.
As per your query you have permanat tanning problem. There are 6 types of skin in human beings. In Indian skin it is more sensitive to tannin while is less sensitive to burning. It means Indian skin on exposure to sun has more of the tendency to get darkened.
It is a common and normal phenomenon to protect ourselves from the damaging effect of sunlight which can cause sun burns.
Now for the part of permanent tanning is a non specific term. Tanning can be continuous but not permanent. The reason being our skin is renewed everyday and by this renewal process our superficial dark skin gets shed off everyday. But if the sun exposure is continous and high then the skin also has the tendency to get darkened day by day.
For the betterment there are some suggestions:
1. Apply sunscreen on face eeryday half an hour before going outside and reapply after 3 hour if in sun.
2. Do sun protection by clothes on rest of the body. It is the best, cheapest and most effective way to prevent sun tanning
3. Eat a lot of green leafy vegetables, salads and seasonal fruits in everyday schedule.
4. Keep yourself hydrated by at least 10-15 glasses of liquids everyday.
5. You can use certain lightening creams under dermatological guidance by which the benefit can be seen after 3-4 months of continuous usage.
Hope these information are helpful.
With good health wishes"
Dr Sanjay Kumar Kanodia