The relative risk of breast cancer decreases 7.0% for each child born by a woman and by 4.3% for every 12 months of breastfeeding. The incidence of breast cancer in developed countries would be reduced by more than half, from 6.3 to 2.7 per 100 women by age 70, if women even just had the average number of births and lifetime duration of breastfeeding that had been prevalent in developing countries until the middle of the last century. [Breast cancer and breastfeeding: collaborative reanalysis of individual data from 47 epidemiological studies in 30 countries, including 50,302 women with breast cancer and 96,973 women without the disease -
Why is there this benefit to motherhood? Well, first of all I would say because there are earthly consequences to not following God's will. But scientifically, I can tell you that it is because breast cancer is caused by exposure to high levels of estrogen. This happens every month near the end of a woman's period. The more children one has and the longer one breastfeeds them, the fewer periods one has, and therefore the less exposure to the harmful effects of high estrogen levels.
There is an additional benefit to having the first child early in life. When a woman has her first child and breastfeeds that child, the milk-producing cells of her breasts are permanently changed into a more cancer resistant type ("type 3 lobules"). The longer one waits to obtain this important cancer resistance, the longer these more cancer-vulnerable cells are exposed to high estrogen, increasing the risk of cancer later on. And it is these cancer vulnerable cells which are at risk for the factors like a high intake of red meat, etc.
God obviously built in physical consequences to the behavior of delaying and reducing childbearing. Breast cancer used to be considered the "nuns' disease." Now most women avoid children like nuns but don't live like nuns, making themselves not much different than prostitutes. They even increase the levels of estrogen they are exposed to by taking birth control pills that artificially trick the body into thinking it is pregnant, though there is no baby born or nursed. The same damage happens with abortion. These sinful actions actually make the breast tissue more susceptible to cancer than that of a nun by a process that would take more time for me to explain.
These are the real reasons for the epidemic of breast cancer in our modern age, not red meat. Those who delay and reduce childbearing for careers, personal freedom, or whatever reason, are not ever going to entirely reverse the damage they cause to their health simply by avoiding red meat. Likewise, women likely don't need to avoid red meat if they follow God's will and have as many children as he wants to bless them with and nurse them as God provided them the natural ability to. That's not a guarantee that one won't get cancer. Everything in moderation, except childbearing and breastfeeding. In that area of life it's hard to overdo it. Be fruitful and multiply!!!