Hello Sir,
By sugar, I presume you mean diabetes.
Type-2 diabetes in about 50 percent of people is asymptomatic- that means they do not have any symptoms. It is found out incidentally by doing blood glucose test for some other reason. In about 50 percent, the patients have symptoms like loss of weight, increased hunger and thirst, increased urination, tiredness, skin problems etc.
To prevent getting diabetes you need to consume a good healthy and well balanced diet with plenty of vegetables. Avoid/restrict processed food and food made of maida, avoid junk food and deep fried items. Restrict or avoid sweets/chocolate, cakes etc. Take at least 2 fruits everyday. Take adequate quantities of protein-dal/eggs/non-veg. Take normal quantities (at least 1/3 of your plate) of carbohydrates like rice, roti etc. Take milk, buttermilk etc.
Do at least 45 min of exercise everyday-running, cycling, swimming etc
Do not become overweight or obese.
If you have diabetes I would suggest to see a doctor as self-medication is dangerous.
I hope this helps you
Thank you.