Keto is definitely an anti- cancer diet . Deriving energy for...

Keto is definitely an anti- cancer diet .
Deriving energy for cells from fats and only complex carbohydrates , rather than simple sugars which provide the glucose hits .

Oestrogen . Tricky .
Definitely post- breast cancer treatments can involve suppression of oestrogen or drug treatments which compete for oestrogen receptors as maintenance treatment for oestrogen relevant cancers.
(This I’m way out of field commenting on also as I’m not an oncologist or gynaecologist )

But the evidence for cancer causation from supplemental oestrogen therapy post - menopause is not really there as I understand it .
The benefits from oestrogen far out-weigh the risks to women’s health generally .

Oestrogen receptors are located throughout the body including in the brain - so the lack or depletion of it causes a lot of issues and can cause considerable distress and impact on life + more likely weight gains & can be considerable impact on quality of life and health . Decreases in movement and exercise performance , deceased bone strength risks etal, as well as increased cardiac disease and heart risks and even higher risks of memory loss /dementia/ Alzheimer’s ? & neurological diseases?
As well - oestrogen supplements post menopause decrease the risk of colorectal cancer ? ( I believe ) , and is an example of oestrogen decreasing the risks of certain cancers where the cancer incidence actually goes up - after loss of oestrogen.