You have probably read a lot of the stuff l have on GH and IGF-1 levels. There seems to be a belief that higher than normal levels will more than likely increase the rate of growth of existing growths, but l have not found a lot of information of this causing the growths in the first place. Because of your family history the smart move would be to not use hgh or peptides that take your lgf levels above normal.
With digestion that's such a controversial and individual thing, all the dieticians and medical field say eat high fibre, low fat, so many serves of fruit and vegies a day eat plenty of whole grain carbs and so on. For me l use to eat like this, never touched sugar or processed food, would take probiotics eat yogurt all the healthy stuff. Even doing all this through early to mid 40's my digestion was totally fucked. l had daily gut pain, heartburn, my gut felt like it was at war everyday. l think even in these so called healthy ways of eating there will be certain foods that are causing your digestion problems. l know for me l could'nt be bothered trying to work out the problem foods so l tried the most restrictive elimination diet there is, the carnivore diet. With in 6 weeks of adapting to the diet l had zero gut problems. That's with no probiotics, no fibre, no carbs. just lots of protein and fat. l have been eating like this for more than 6 years never even had an upset tummy or been sick with even a common cold once in those 6 years. There will definitely be some problem foods, no matter how healthy you think your eating that will be causing your digestion problems.