Written by: Bonnie Feldman, DDS, MBA, Becca Malizia, BS, Ellen M. Martin
It is easy to feel like an outsider in a digital world where everyone seems to be blogging, Instagramming, Tweeting, about the new diet or exercise that revolutionized their lives. It is easy to think that you alone are struggling to be healthy in this increasingly information-driven society with too many success stories. But the truth is, most people have not found the answer to living their best lives. Most people haven’t found the optimal diet that changed everything. The truth is: you are unique, your body is one of a kind, and the diet that worked for your best friend or someone with the same autoimmune diagnosis, even your sibling, may not be the best for you! The search for the best diet is an ongoing process, and a very personal journey.
What Makes You Unique
Let’s take a step back and discuss the uniqueness of you. Although humans share some 99% of their DNA, that ~1% difference is enormous (1). For one thing, 1% of 6 billion DNA letters is a big number. But many phenotypic variants, including diseases, are the result of codon repeats, misses or other differences at the phrase or sentence, rather than the individual letter, level. Furthermore, pleiotropy (multiple gene interactions) and epigenetics (changes in gene expression) add additional levels of complexity challenging the dogma of one gene-one protein-one trait. Your microbiome is a whole other aspect of the uniqueness of you! The beneficial microbes that live inside your mouth, nose, GI tract and genitals differ from person to person, affected by things such as the environment, what you eat, and even who you are dating or if you have a pet!
So Let’s Break it Down…
Genetics: Even though humans share 99+% of their DNA, your specific genome has never existed before, and will never exist again. Your kids share only parts of your DNA, just like you did with your parents. In fact, you may have no genes in common with many of your ancestors beyond the great-grandparent level. Your DNA double helices loops together as chromosomes. Humans have 23 pairs of chromosomes (22 autosomal and one pair of sex chromosome). You inherit half of these from your mom, and half from your dad. Because of sexual reproduction, and the miracle of independent assortment (genes don’t always stay on the same chromosome you inherited them from) you are a completely unique combination of your parents’ DNA. Each sperm your dad produced and egg your mom produced is a unique combination of the DNA that they inherited from their parents. Natural and sexual selection has shaped sexual reproduction to maximize variation as well as favor certain gene combinations over others…
Multiple alleles, epistasis, polygenic traits and pleiotropy: Although the “one gene produces one trait” is still widely taught, it is becoming increasingly clear that picture, while true for some traits, is too simple for many.
- More than two alleles at many single loci have been recognized for decades. Blood types and hemophilia are two of the better-understood examples.
- Pleiotropy, where a single gene affects multiple traits, may be a factor in the variable, hard-to-parse symptoms of autoimmune diseases (2).
- A more recent understanding of polygenic traits, where multiple genes (not just multiple alleles of the same gene), including ones on distant chromosomes, act together to produce a particular phenotype (e.g., height, blood pressure, autoimmune disease) may be even more important in explaining differences in disease presentation and responses to medications.
Epigenetics: It used to be thought that your genetics and the environment were the only factors, operating on different ends of a spectrum, that made you unique. As a result, identical twin studies were of great importance because in theory, they take genetics out of the equation and focus only on the environmental. Epigenetics is a new field that focuses on the way in which your environment, the chemicals you are exposed to and the food that you eat, can change DNA expression. Epigenetics has become important in autoimmune diseases because differences in expression may explain why two people (e.g.,twins) with the same genes, have different weights or disease profiles (3). It is now thought that diseases such as Alzheimer’s, Crohn’s, even autism, are polygenic, and many different small epigenetic changes in these multiple genes complicate the picture further. In her book Zoobiquity, Dr. Natterson- Horowitz describes epigenetics as rapid evolution “that the genes we pass on to our children can differ from the ones we inherited”(4).
Microbiome: Recently, the microbiome has fed many new fads. So many products now advertise the fact that they have pre- and/or probiotics. Every grocery store is swimming in different kombucha brands, and many food items have added probiotics. Even many pet foods now contain probiotics! (my dog’s included). The microbiome is a crucial part of the body, important in metabolism, regulation and overall body function. There are 38 trillion bacteria that make up your microbiome community (5). Both the oral and gut microbiomes have unique compositions and vary from person to person. Animals too have their own microbiomes, and living with pets can also alter your microbiome (usually in a positive way!).
- Oral microbiome: In and around your mouth, many things affect your own community of oral bacteria, from the food you eat to who you kiss, whether person or pet! New products are hitting the market, focussing specifically on the maintenance of the oral microbiome. Read more about your oral microbiome and probiotics in some of our other blog posts here: The Mouth: Fun, Flirty, and Full of Bacteria; The Rising Culture of Probiotics, Pills, and Fruity Tea to Reduce Oral Pathogens; The Oral Microbiome: Critical for Understanding Oral Health and Disease; Hyperbiotics: The Mind behind the probiotics, for the Body, driven by Soul
- Gut microbiome: In your stomach and the rest of your digestive tract, the gut microbiome has been the main focus of the microbiome movement and is a key player in metabolism. Your bacterial composition can even signal to your brain when you are hungry, and can affect things as specific as food cravings. A healthy gut microbiome consists of a wide variety of different species of bacteria. This composition can be disrupted by your environment as well as antibiotics. Dysbiosis is when your gut microbiome becomes imbalanced, and can result in a wide variety of short or long term GI problems. It has also been implicated in many autoimmune diseases as well as other long term health problems. To read more about your gut microbiome and autoimmune diseases check out our post here: Trust Your Gut- Your Microbiome & Autoimmunity; Pre & Probiotics: The Role of Fiber and Diet on Microbial Health in an Age of Antibiotics; Punk Rawk Labs: A Dabble In Delicious, non-Dairy Cheese
Now Back to FOOD…
Food is an incredibly important component of you. Your diet, what food you ingest, is the currency of fuel and can affect your microbiome as well as your genetics! If you aren’t eating the right nutrients, it’s not surprising that your body can start to function improperly. How you choose to fuel your body has the potential to not only cause but help mitigate, prevent, and cure disease! These concepts are the basis for a movement coined “Food as Medicine”. Embracing food as medicine is another way to get your mind on the right path. At the end of the day, your food choices DO matter, and are a key factor in your overall health. But which foods work as medicine for you?
How do you navigate all the clutter to find a diet that works with your unique phenotype? Does your ethnicity matter? How do your taste preferences factor in? Are you eating things that you like but are bad for you? Are you avoiding foods that might be good for you? Are you allergic or sensitive to certain proteins or FODMAPS? Do you have religious constraints or ethical objections to animal foods? Are you trying to gain muscle or lose weight? Can DNA tests help?
Just HOW do you find YOUR optimal diet?…
There is HOPE!
Amidst the clutter and fads, diagnosed and undiagnosed symptoms, and the overwhelming plethora of information, we are here to help you discover different aspects of what makes you unique and help you reach your optimal health! Although learning about genetics, epigenetics and your microbiome can be complicated, they are all different avenues you can explore to better understand yourself and your body. At Your Autoimmunity Connection you can feel at home in a shared community of people who are going through the same thing as you! We are here to put on our scientific spectacles to give you an educated patients perspective to provide you the tools you’ll need to navigate this information, and find your shortest route to eating the best diet for YOUR optimal health!
Stay tuned as we sort out the hype from the hope, the fluff from valuable information in our new food blog series: Food Matters.
- People Are Not as Alike as Scientists Once Thought | Understanding Genetics. https://genetics.thetech.org/original_news/news38. Accessed 20 July 2018.
- Lobo, I. Pleiotropy: One Gene Can Affect Multiple Traits. Nature Education 1(1):10.2008. Accessed 20 July 2018.
- Quintero-Ronderos, Paula, and Gladis Montoya-Ortiz. “Epigenetics and Autoimmune Disease” Autoimmune Diseases, 2012, doi: 10.1155/2012/593720.
- Natterson-Horowitz, Barbera. “Zoobiquity, The Astonishing Connection Between Human and Animal Health”. ch. 1, pg.19. 2012. https://yourautoimmunityconnection.files.wordpress.com/2018/07/66b31-excerpt-chapter1-drhousemeetdrdolittle.pdf
- Sender, Ron, et al. “Revised Estimates for the Number of Human and Bacteria Cells in the Body.” PLoS Biology, vol. 14, no. 8, Aug. 2016. PubMed Central, doi: 10.1371/journal.pbio.1002533.