Am just over 40 years and have never see a doctor for any major check up, is this advisable, am i at any risk, cause i really don't have any major reason to?

There is always risk: Probably a few things you should consider..Family history of disease ? All immunizations up to date? One prior cholesterol check? Obesity, alcohol, tobacco, risky behavior, sexually transmitted disease? If you have addressed all these then the next "milestone" is age 50 when screening for colorectal canccer should be considered.