Nutrigenetics: Lactose Intolerance and Genetic Expression

With current research, we are now understanding the complexity and awareness of gene variants and how they change our metabolic function. We see now that these nutrigenetic diet-gene interactions are associated with an increased risk of different diseases. Following this same logic, we are able to predict an individual’s response to specific foods. The reason that one individual is able to drink caffeine until bed and another is not all comes down to our genes. 

Food Responsiveness 

The most common foods that are associated with genetic variations include:

• Lactose non-persistence 
• Salt Sensitivity 
• Taste
• Gluten
• Iron 
• Caffeine
• Polyunsaturated Fat 
• Alcohol 

Lactose Non-Persistence 

Lactose tolerance is a prime example of how humans evolved and created a new trait to take advantage of a food source. This resulted from a change in the way our gene is regulated. As infants, we are lactose tolerant. Lactase is the enzyme used to digest lactose (the sugar found in milk). However, once we wean our bodies stop producing lactase and we become lactose intolerant. There is a mutation in the genes that some carry keeping the lactase switch on. This is what we refer to as Lactose Persistence.  

In order for a gene to be expressed, it needs to be transcribed, translated, and then properly processed to produce a protein. Those who are able to digest lactose have the LCT gene expressed in the cell of the small intestine. Those who are lacking in the enzyme may not be able to digest lactose. 

LCT Gene 

For those who have lactose intolerance, the LCT gene transcription is reduced, leading to a low level of lactase. To turn off LCT it involves blocking an activator or turning up a repressor. In fact, it is theorized that lactase persistence is a human evolutionary adaptation to drinking milk from domesticated animals. The mutation in the gene started to appear around the same time as the domestication of cattle. There is not an exact explanation for the mechanisms of lactase persistence. One theory is that the mutation causes the activator molecules to bind more strongly to the enhancer region, while the other theory is that the repressor molecules no longer bind to the enhancer. 

Specific Example:

In northern Europe, the mutation found was the binding of the transcription faceted Oct -1 was strengthened to the enhancer region. Oct-1 is an activator for LCT. Therefore, it would increase the transcription of the LCT gene. 

Lactase Non-Persistence (LNP or Lactose Intolerance) Symptoms

After the consumption of lactose, those who are lactose intolerant experience diarrhea, abdominal pain, or flatulence. These symptoms arise by the decreased ability to hydrolyze lactose from a decrease in lactase expression. Lactase is coded by the lactase gene (LCT). For more information, please refer to the article below: 

“Associated of the LCT-13910C>T Polymorphism With Obesity and Its Modulation by Dairy Products in a Mediterranean Population”

SNP 

The most common SNP is tested and found in European/Caucasian populations. It is located at -13910 bp upstream from the LCT gene. Studies show that the SNP is functional and associated with changes to the LCT gene expression. Those who have the C allele have almost no detectable levels of lactase production. For more information, please refer to the gene data base below:

Rs4988235 

“Leaky Gut” 

One of the reasons understanding genetic variation and gene expression in relation to food is so important is the other adverse effects it has on the body. When the body does not produce certain enzymes to properly digest a substance (in this case lactose), it results in damage to the gut lining. The gut is comprised of tight junctions responsible for controlling what nutrients are let in and out. With the body seeing food nutrients as foreign invaders it can not break down, it causes an inflammatory response. Over time, this constant inflammatory response triggers antigen production and the tight junctions become inflamed and highly permeable. This allows the improper nutrients to enter and leave the gut, ultimately being released back into the bloodstream causing more inflammatory responses. 

Vibrant Wellness uses a gut zoomer panel to assess the integrity of the gut and specific gut commensals, gut pathogens, and inflammation and digestive insufficiencies an individual may have. A sample report is shown below: 

Leaky gut and inflammation and been connected to almost every single chronic health condition, including autoimmune diseases. The gut is responsible for a wide variety of overall human health. Taking care of the gut is highly important and should never be overlooked. 

From The Kitchen To The Genes 

One can see that genetic expression is constantly changing and our gut health is important. However, many do not understand the deep connectivity of the two. Healthy organic fruits, vegetables, and grass-fed meat feed our microbiome by providing essential micronutrients that positivity make an impact on our genes and their pattern of expression. In fact, there is a special sugar that is found in leafy greens that is beneficial to the bacteria in our gut. This sugar is referred to as sulfoquinovose and is the only sugar known to contain sulfur. Sulfur is essential to create enzymes, hormones, antibodies, and proteins! By adding in leafy greens to your smoothie in your morning, you are not only kick-starting your health but decreasing inflammation! Below are some smoothie recipes that include greens to kickstart your gut health. 

If you are curious about your gut health, current symptoms, or want to know more about your specific genes and risk factors, you can start by reviewing the metabolic assessment below: 

Inflammation plays such a large role in our daily health. By reducing inflammation and improving our gut health, we are ultimately improving our genes and their genetic expression. Lactose intolerance takes on an entirely new meaning when you realize it has to do with gene expression and human evolution. -Kenna Vaughn, Senior Health Coach 

References: 

Corella D, Arregui M, Coltell O, et al. Association of the LCT-13910C>T polymorphism with obesity and its modulation by dairy products in a Mediterranean population. Obesity (Silver Spring). 2011;19(8):1707‐1714. doi:10.1038/oby.2010.320 

The scope of our information is limited to chiropractic, musculoskeletal, and nervous health issues or functional medicine articles, topics, and discussions. We use functional health protocols to treat injuries or disorders of the musculoskeletal system. Our office has made a reasonable attempt to provide supportive citations and has identified the relevant research study or studies supporting our posts. We also make copies of supporting research studies available to the board and or the public upon request. To further discuss the subject matter above, please feel free to ask Dr. Alex Jimenez or contact us at 915-850-0900.