Breast Cancer, Nutrigenomics and Oestrogen Detoxification

WHAT IS NUTRIGENOMICS? 

Nutrigenomics is an interdisciplinary field of study that investigates the relationship between nutrition, genes, and health. Derived from the words “nutrition” and “genomics,” nutrigenomics seeks to understand how the foods we eat interact with our genetic makeup to influence our health positively or negatively. This is a departure from the traditional “one-size-fits-all” model of nutrition, where dietary recommendations are made for the population at large. 

The importance of nutrigenomics extends beyond mere curiosity. Diseases such as diabetes, obesity, cardiovascular diseases, and even certain types of cancer have both genetic and nutritional factors that contribute to their onset and progression. By understanding how specific nutrients interact with particular genes, nutrigenomics has the potential to offer targeted prevention and treatment strategies. For instance, understanding which genes are influenced by certain dietary components can help in creating a nutrition plan that can support these genes, affecting disease risk or progression. 

HOW NUTRIGENOMICS OFFERS A PERSONALISED APPROACH TO NUTRITION 

The central promise of nutrigenomics is personalisation. The idea is not just to understand what foods may be generally “good“ or “bad” for health, but to determine what foods may be beneficial for your health based on your genetic makeup. With the advancement of genome sequencing technologies, it has become increasingly affordable and accessible to assess your genetic profile. This profile, combined with nutrigenomic research, can guide personalised dietary recommendations. 

Imagine two individuals with a family history of breast cancer. One of them may have a genetic profile that suggests a faster rate of oestrogen detoxification, while the other may not. Nutrigenomics can potentially offer each of them a personalised nutrition plan designed to either support their natural oestrogen detox capabilities, thereby affecting their overall breast cancer risk differently. 

This personalised approach extends to micronutrients, macronutrients, and various food groups, allowing for diets to be tailored to individual metabolic types, health conditions, and even lifestyle factors. As a result, nutrigenomics transforms the act of eating from a general health practice to a targeted intervention, optimising health outcomes at an individual level. 

UNDERSTANDING THE LINK BETWEEN NUTRIGENOMICS AND BREAST CANCER RISK 

THE GENETIC FACTORS THAT INCREASE SUSCEPTIBILITY TO BREAST CANCER 

Breast cancer is a complex disease influenced by a variety of factors, including genetics. Certain genetic mutations, most notably the BRCA1 and BRCA2 genes, have been closely associated with a significantly higher risk of developing breast cancer. These mutations interfere with the cell’s ability to repair damaged DNA, potentially leading to uncontrollable cell growth and cancer. However, it’s important to note that having these mutations does not guarantee that one will develop breast cancer; it simply increases the risk. 

Aside from BRCA mutations, other genetic markers, known as single nucleotide polymorphisms (SNPs), have been identified as less potent but still relevant factors that may influence breast cancer risk. These SNPs may play roles in hormone regulation, immune response, and cellular growth and repair mechanisms, among other functions. 

HOW NUTRITION INTERACTS WITH GENETICS 

Nutrigenomics offers intriguing insights into how nutrition can interact with these genetic factors. Certain nutrients have been shown to influence gene expression, either activating or deactivating genes that are linked to breast cancer. 

For instance, nutrients like folate, found in almonds and avocados, may interact with genes involved in DNA repair. Omega-3 fatty acids from flaxseeds may play a role in downregulating genes associated with inflammation, which is a known contributor to cancer progression. On the flip side, high intake of processed foods has been linked to the activation of genes that promote inflammation and tumour growth. 

Additionally, nutrients like indole-3-carbinol (I3C) found in cruciferous vegetables (e.g., broccoli, cauliflower and kale) may play a role in oestrogen metabolism, supporting the detoxification and removal of harmful oestrogen metabolites from the body. 

THE ROLE OF GENES IN HORMONE PRODUCTION, REGULATION AND DETOX 

Hormones like oestrogen play a critical role in various bodily functions, from reproductive health to bone density. However, an imbalance in hormone levels or their metabolism can lead to a variety of health problems, including breast cancer. Genes have a significant influence on how hormones are produced, regulated, and detoxified in the body. 

HORMONE PRODUCTION 

Certain genes are responsible for the biosynthesis of hormones like oestrogen. For example, the aromatase gene (CYP19A1) plays a crucial role in converting androgens into oestrogens. 

HORMONE REGULATION 

Genes like the oestrogen receptor genes (ER-alpha and ER-beta) regulate how the body responds to oestrogen. Mutations or variations in these genes can impact sensitivity to the hormone, potentially affecting breast cancer risk. 

HORMONE DETOX 

Genes related to liver enzymes play a vital role in hormone detoxification. These include the cytochrome P450 family of genes, which help convert active forms of oestrogen into less active forms that can be easily excreted from the body. 

THE SIGNIFICANCE OF OESTROGEN DETOXIFICATION IN BREAST CANCER RISK 

Oestrogen detoxification is the metabolic process by which the liver transforms oestrogen into less potent metabolites for excretion. This detox pathway is crucial for maintaining hormonal balance and reducing the risk of oestrogen-sensitive cancers. While the liver is the primary site for oestrogen detoxification, its metabolites are ultimately excreted through urine and faeces. 

Oestrogen detoxification is particularly significant in the context of breast cancer because some breast cancers are oestrogen-receptor-positive, meaning they grow in response to oestrogen. Inadequate detoxification can lead to a buildup of harmful oestrogen metabolites that can bind to these receptors and promote tumour growth. 

Additionally, specific genetic profiles may either speed up or slow down the rate of oestrogen detoxification, which can be a pivotal factor in breast cancer risk. For individuals with a slower detoxification rate, implementing nutritional strategies to support this process may be particularly beneficial. For those with a faster rate, balancing out oestrogen levels to avoid detrimental low levels may be more appropriate (1). 

Nutrigenomics can provide insights into which nutritional strategies may be most effective for oestrogen detoxification, based on one’s genetic makeup. By understanding these mechanisms, individuals can take proactive steps in their diets to mitigate the risks effectively.