{"id":2272,"date":"2019-10-22T19:58:14","date_gmt":"2019-10-22T23:58:14","guid":{"rendered":"https:\/\/www.shortform.com\/blog\/?p=2272"},"modified":"2022-03-09T10:17:14","modified_gmt":"2022-03-09T14:17:14","slug":"is-breast-cancer-hereditary","status":"publish","type":"post","link":"https:\/\/www.shortform.com\/blog\/is-breast-cancer-hereditary\/","title":{"rendered":"Is Breast Cancer Hereditary? BRCA Isn’t the Biggest Factor"},"content":{"rendered":"\n

BRCA gene mutations have gotten a lot of attention, and for good reason: The discovery of mutations in BRCA-1 and BRCA-2, the breast cancer genes, can help you understand your breast cancer risk<\/a> and get the preventative treatment you need. But is breast cancer really caused by your genetics? Is breast cancer hereditary?<\/p>\n\n\n\n

We’ll cover the role of the BRCA genes in breast cancer, discuss the role of genes in disease risk more generally, and look at other, perhaps more influential, breast cancer risk factors you should be aware of.<\/p>\n\n\n\n\n\n\n\n

BRCA Genes: Is Breast Cancer Hereditary?<\/strong><\/h2>\n\n\n\n

BRCA gene mutations definitely increase your risk of getting breast cancer, but probably not as much as the media tells you. Although the \u201cbreast cancer genes,\u201d BRCA-1 and BRCA-2, have received a lot of attention, studies find that less than 3% of breast cancer cases are genetic.<\/strong> Additionally, only 0.2% of the population carries BRCA gene mutations, so only a small percentage of breast cancer cases can be attributed to them.
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The fact that half of the women who carry BRCA-1 or BRCA-2 never get breast cancer also demonstrates that your genes are not your destiny.
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It\u2019s not that the discovery of the breast cancer genes wasn\u2019t important. But we need to pay attention to not only who carries these genes but also what causes them to be expressed. A diet high in animal fats and proteins has been shown to act as a trigger for both carcinogens and cancer-causing genes like BRCA-1 and BRCA-2.<\/p>\n\n\n\n

Is breast cancer hereditary? Yes and no. You can inherit BRCA-1 and BRCA-2 mutations from either one of your parents. But 97% of breast cancer cases are not <\/em>hereditary.
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Your Power Over Genetics and Disease Risk<\/h2>\n\n\n\n

Just as we’ve been told to connect breast cancer and genetics in our thinking about the disease, we’ve been told that our genes play a huge part in whether or not we’ll develop many diseases.<\/p>\n\n\n\n

But genes alone don\u2019t cause disease\u2014we have considerable control over which genes get expressed.<\/strong><\/p>\n\n\n\n

Genetics only determine 2-3% of your overall cancer risk.<\/strong> <\/p>\n\n\n\n

Dormant genes, genes that aren\u2019t expressed, have no effect on our health. Genes only affect us when they\u2019re activated, and diet is one of the biggest triggers of gene activation.
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As demonstrated in cancer studies, researchers can turn \u201cbad\u201d genes on and off by altering the amount of animal protein they give to mice.
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The idea of dietary triggers explains why, in populations made up of people who share a genetic heritage, disease rates vary widely.
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Further, genes evolve slowly, changing minimally, or not at all, over hundreds of years. But disease rates change at a much faster rate, sometimes in a period as short as a year. Therefore, we can\u2019t blame changing genes for increasing disease rates.<\/p>\n\n\n\n

Even the risk for highly genetic autoimmune diseases<\/a> like multiple sclerosis<\/a> isn’t entirely controlled by genetics. Genes account for 25% of your total MS risk. That means 75% of your disease risk is environmental and largely under your control.<\/strong> Studies show that migrants adopt the MS risk of their new home country, showing that your genes aren\u2019t the most important factor in the disease\u2019s development.
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Studies have shown this time and time again. Japanese men living in Japan have a lower rate of Alzheimer\u2019s than Japanese American men living in Hawaii. Africans have a lower rate of Alzheimer\u2019s than African Americans. Because in each of these studies the groups compared shared a genetic heritage, the findings demonstrate that genes are not as important as environmental factors in the formation of Alzheimer\u2019s.
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In summary, genes give us dispositions, but they don\u2019t dictate what diseases we\u2019ll get.
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The China Study<\/strong>: More Reason to Believe Most Breast Cancer is NOT Hereditary<\/h2>\n\n\n\n

Studying people in rural China allowed researchers to rule out genetics as a major factor in disease formation, including breast cancer formation, because, compared to other areas of the world, rural China contains populations with homogeneous genes. 87% of the Chinese are of the same ethnic group, the Han.
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Additionally, 90-94% of the adults studied were living in the county where they were born. The lack of migration meant that the genes in the population were relatively similar.
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Even though the Chinese share the majority of their genes, they don\u2019t all have the same cancer risk.<\/strong> For example, some Chinese counties have much higher cancer rates than others, and some types of cancers are much more prevalent in some places. 
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As mentioned earlier, genes make up only 2-3% of a person\u2019s total cancer risk. Therefore, the other 97-98% must be environmental or related to lifestyle. The fact that the Chinese share most of their genes but get different cancers supports this statistic.<\/p>\n\n\n\n

Other Breast Cancer Risk Factors<\/strong><\/h2>\n\n\n\n

If BRCA gene mutations play only a small role in breast cancer risk, what risk factors should you be aware of?<\/p>\n\n\n\n

1. High Blood Cholesterol<\/strong><\/h3>\n\n\n\n

Both dietary fat (found in greater quantities in animal foods than in plant foods) and animal proteins have been shown to increase cholesterol.
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2. Prolonged Exposure to Female Hormones <\/strong><\/h3>\n\n\n\n

These hormones include estrogen and progesterone. The earlier a female starts menstruating, and the later she starts the process of menopause, the greater her exposure to estrogen over her lifetime.
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Animal foods seem to play a part in increasing cancer risk at every stage of a woman\u2019s life:
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