Learn what personalized nutrition is and why "one-size-does-not- fit-all" when it comes to nutrition.
One of the pillars of the functional medicine approach is personalized nutrition. Personalized nutrition is based on the concept of biochemical individuality, an important understanding that we all have different biochemical and genetic makeup which makes us as unique as our fingerprints are. When it comes to nutrition, it means that we all have different nutritional requirements to sustain vital functions in our bodies.
Biochemical Individuality
Biochemical individuality has a profound effect on all systems and processes in the body from blood sugar regulation, to stress response to how well our detoxification and hormonal pathways work. The research conducted in the 1950s by Dr. Roger Williams, an American world-renowned biochemist, revealed that while RDAs (recommended daily allowances) may satisfy the nutritional needs of some people, they are not sufficient or adequate for all [1]. RDAs would be more useful if we all had the same nutrient requirements and metabolized and absorbed nutrients in the same way. But nothing can be further from the truth. RDAs do not take into account our unique biochemistry, genetics, lifestyle, social and emotional environment.
For example, two individuals with different levels of psychological stress would differ in the way they digest and absorb nutrients. High stress can affect digestion in many ways, from loss of appetite, nausea, and diarrhea, to lowered production of digestive enzymes, and exacerbating conditions like IBS and peptic ulcers. Chronically activated “fight or flight” response changes the levels of stomach acid, and decreases oxygenation and blood flow to the intestines which causes inflammation. Another example is an individual with an autoimmune condition like celiac disease who would have a diminished ability to absorb nutrients because of the damaged intestines and the lack of the enzymes necessary for proper and effective nutrient absorption. People who are exposed to various environmental toxins may have a higher need for nutrients that aid detoxification. Likewise, individuals with high levels of physical activity like athletes will have higher nutritional needs. Williams discovered that anatomical variations in the sizes and locations of our internal organs determine their function and unique biological needs. He also demonstrated that identical twins can vary in their nutritional requirements for optimal function. Twins may share the same genes but due to the differences in their environment may have a different expression of their genes later in life. Williams was the forefather of the emerging science of epigenetics.
SNPs and Epigenetics.
We know that people with various inborn errors of metabolism are genetically predisposed to certain conditions. They need to take certain precautions
when it comes to their diet and lifestyle. One such condition is G6PD deficiency which can cause hemolytic anemia. G6PD-deficient individuals need to avoid fava beans and be careful with vitamin C supplementation [2]. They are also more susceptible to Type II diabetes and thus should focus on optimal blood sugar regulation. Likewise, for people with hemochromatosis, it is wise to avoid high-iron foods.
We all have some slight genetic deviations, better known as SNPs, or single nucleotide polymorphisms. The above examples are some of the most significant deviations from the general population, but there are many that are more subtle. SNPs are single-letter changes in our genetic code. SNPs are not mutations but normal variations among all people. It is estimated that there are roughly 4 to 5 million SNPs in any person’s genome [3]. Most SNPs have little to no effect on human health. However, some can have an impact on important biochemical pathways like methylation and detoxification. One of the most studied SNP is MTHFR. Individuals with this variation may have an increased need for folate, B6, and B12. These nutrients support methylation and detoxification, and help reduce the risk of cardiovascular and neuropsychiatric diseases. Individuals with an SNP in COMT (catechol-O-methyltransferase) enzyme, may need more magnesium in their diet than those with normal enzyme activity.
With that in mind, it is important to undertand that "faulty" genes are not what determines our health outcomes. Our lifestyle and environment do. This is exactly what the science of epigenetic studies, the effects of our environment like food, lifestyle, stress on the expression of our genes. If you are interested in learning more about this topic, I highly recommend a book by Dr. Ben Lynch "Dirty Genes" where he goes into great detail explaining how it works. [5]
Microbiome. A critical piece of the puzzle.
While it is helpful to know your genetic profile, there is one more factor that is even more important, in my opinion. It is your microbiome. Even though science has only scratched the surface of learning about the role of the microbiome in human health, what we do know is mindblowing. The inner microbial ecosystem is responsible for a myriad of functions. Not only does it help digestion and assimilation of nutrients, but it also makes vitamins, neurotransmitters, and short-chain fatty acids that are needed for the regulation of metabolism, inflammation, and disease [3]. Microbiome also controls your immune system and communicates with your brain directly affecting your mood. Differences in our microbial diversity can greatly affect our nutritional status and overall health. In functional nutrition gut health is central to addressing many chronic conditions.
Personalized nutrition.
Biochemical individuality is the reason why one person loses weight on a low-carb diet, while another one gains it. There is no such thing as a perfect diet. Assessing a patient's nutritional status is one of the most important pillars of functional medicine. Working with a functional nutritionist will give you a better understanding of your unique dietary and lifestyle needs. Knowing your biochemical makeup will make you more in tune with your body and environment. You will understand your symptoms and learn what your body is asking you for. It will make it easier for you to make everyday dietary and lifestyle choices that nourish you, your genes, and your microbiome.
References:
1. Williams R.J. (1998) Biochemical Individuality. The key to understanding what shapes your health .The basis for the Genetotrophic concept. Keats Publishing, Inc.
2. Quinn, J., Gerber, B., Fouche, R., Kenyon, K., Blom, Z., & Muthukanagaraj, P. (2017). Effect of High-Dose Vitamin C Infusion in a Glucose-6-Phosphate Dehydrogenase-Deficient Patient. Case reports in medicine, 2017, 5202606. https://doi.org/10.1155/2017/5202606
3. National Library of Medicine.
4. Tan, J., McKenzie, C., Potamitis, M., Thorburn, A. N., Mackay, C. R., & Macia, L. (2014). The role of short-chain fatty acids in health and disease. Advances in immunology, 121, 91–119. https://doi.org/10.1016/B978-0-12-800100-4.00003-9
5. Lynch.B Dirty Genes. (2018) A breakthrough program to treat the root cause of illness and optimize your health. HerperOne.
I am ever grateful to be the recipient of Natalia's wisdom and coaching. I now have a healthier diet, a happy gut, and love my resulting wellness. Thank you, Natalia.