Doctors don't just say it, evidence bears it out. Screening detects way more false positive than true positives. Following everything up is simply not possible, unless you have tons of money and basically making your life about prevention and little else.
There is good medical evidence to support colorectal cancer screening so go ahead and get that (along with other recommended preventive care services) if you meet the criteria.
https://www.healthcare.gov/preventive-care-adults/
Obesity and insulin resistance (type-2 diabetes) greatly increase the risk of many types of cancer. Don't overeat, don't get fat, and exercise enough to keep your metabolism working well.
Critically, risks are cumulative so the chances of cancer depend not on individual events taken in isolation but multiple events combined, and many of them are under your control.
>> and many of them are under your control
This is the societal problem with cancer. If someone gets cancer I'm guessing it might be an incorrect reaction for one to think it was the person's "fault", but the reality is cancer just happens, and it's not a modern phenomena. No one can control the type of cancer they get and no one can control the (unaided) outcome.
My banana comment was partly in jest, but as an example that ionized radiation is found everywhere, and our body is set up to protect, remove, and repair broken DNA on a regular basis.
But there’s a great number of things that increase risks of cancer to the point where you can be well below average cancer risks.
Cancer is scary, because there always looms the unknown causes. Heart disease, less scary, because people have much more control through healthy habits. Cancer, not as much.
She was 5 years out. By all reasonable accounts, she was clear of cancer and had a low risk of recurring. Until it did.
I say this because cancer is fundamentally a numbers game. Very few cancers can be prevented by medical intervention and some of the common ways to prevent certain cancers (HPV vaccines) are controversial, because society is stupid.
So you take your 23andMe, and find out you have a 50% increased risk of developing cancer of some sort. Now what? Do you know what that really means? Do you go to your doctor? What do they say? Do you decide you’re gonna die anyway and embrace van life? Do you go buy squid ink from some Instagram quack for $50/oz?
In business we make a distinction between data and information. This is data that creates anxiety with no purpose.
In my wife’s case, what should she have done? She had elevated, low risk for developing melanoma within 5 years. We knew that, she knew that. Ultimately, cancer is about math and risk. Reduce risk if you can - stop drinking and smoking. The variables you can’t control are fate. Worry won’t affect them, but will affect you.