Thank you for the query.Colon cancer
over the age of 50 is not a hereditary. It is sporadic cancer, so your risk of it is same as population risk. Hemorrhoids do not give weight loss
Constipation most common reasons are bad diet (low fiber and mineral water intake), chronic intestines infection, hypothyroidism
, medicines (ca- blockers, antidepressants) or colon cancer.
As you are almost 50, and your colonoscopy
was 8 years ago, it should be done again. We know that colon cancer development takes approximately 10 years.
You should also improve your diet (start with it and get scheduled for colonoscopy in a meanwhile). Increase fiber rich products, mineral water intake and physical activity (it greatly stimulates intestines to work). Start probiotic supplementation. If it wont help, thyroid tests, stool test should be done.
Hope this will help.