Natural processes are those processes within the human body that are in essence, supposed to happen. The normal functioning that would happen without interference due to some factor outside the human body.
Cancer is not natural, but a disruption of our natural process of cell replacement within the body. This can be caused by infection with a virus, DNA damage due to overexposure to radiation - including the sun, radium, X-rays, chemically caused by overexposure to man’s polluting the environment with endocrine disrupters, breathing in pollutants including cigarette smoke and so on.
Alzheimer’s is similarly not natural as it is an as of yet not fully understood process which causes the brain to attack itself, causing brain damage.
Coronary Artery Disease is also not natural but caused mostly by our modern sedentary, high stress lifestyles and high fat diet - especially UPFs which are very much artificial food like substances that we eat.
Menopause is a natural process, when it goes the way it should which it does for the majority of women meaning they do not get distressing symptoms. Menopause is the adjustment of hormones to transition from fertility to nonfertility. It is only when the adjustment deviates from the natural process that we get unbalanced hormones and a difficult menopause (or andropause).