Natural Urges are called Vegas. According to Ayurvedic Scriptures, These Vegas or Natural Urges include, but, are not limited to:
1. Urge to Belch, Sneeze or Burp
2. Urge to pass Stool, Urinate, or pass gas
3. Ignoring the bodies need to Eat (Hunger), Drink water(Thirst) and, Sleep
4. Cough, Yawning, Hiccups, Heavy Respiration (intense physical activity like running for a long time, weight lifting when heart rate goes very high)
5. Suprression of Shukra (Semen) or unnatural activities related to this
6. Supression of urge to vomit (When gody is trying to get rid of something naturally, not emesis bought about by some medicine)
7. Supression of Tears and thoughts (Grief, Sorrow, Unhappiness and fixated on bad memories, sad things) will actually cause harm.
A student asked me, what if someone is supressing anger?
My response was that it would come under the purview of suppression of urge of thoughts.
If someone is suppressing even healthy or small amount of anger, or, grief and not communicating it. Eventually, as the days become months-then it is a supression.
However, if someone is writing their feelings in a journal, expressing it to a friend, or singing about it, or using some kind of stress relief like meditation or music or mantras, breathing techniques--that is good enough.
There are people who cant stop talking, or cant stop being critical --they are taking their urge to express themselves, their anger and behavior to a level where now it is harming them. So, that is an over expression of urge--Ayurveda tells us to do everything moderately.
In cultures like India- it is okay to Burp or sneeze. It is a cultural issue in this country where we are always trying to be polite.