Learning more about your genes can help you cut through all the confusion about nutrition and give you actual data to work with. Here’s what I learned about my own health markers and genetic risks after having analysis done.
If I drink coffee or tea before drinking fresh orange juice, I develop some odd symptoms. My face gets very warm and flushed. I feel feverish. My throat feels hot, sore, and tight. I suddenly feel very tired. Sometimes I get headaches and nausea, too. The reaction feels similar to an allergic one, but it isn’t quite the same. I noticed the reaction consistently occurred when I consumed coffee before citrus fruit or homemade juice, so I decided to switch the order. Guess what? No more reactions. As long as I don’t have coffee or tea before citrus fruit, I am fine. Reverse the order, and I am miserable for the rest of the day.
I really wanted to know the root cause of this bizarre set of symptoms. Exactly what the heck was going on in my body to cause such a severe and genuinely uncomfortable response?
A trip down the internet rabbit hole via a search of my strange symptoms led me to a website called Gene Food. I’ve been hooked on the site ever since. Nutrigenomics is a truly fascinating field of science, and I believe it has a lot of potential for helping people prevent chronic illness and serious disease.
Note: This article contains affiliate links. After ordering a custom nutrition report and spending a lot of time reading articles on the Gene Food website, we were so impressed that we decided to join their affiliate program. This means that if you click on the links in this article and make a purchase from Gene Food, All About Habits may earn a commission. This does not increase the cost of the product for you, nor does it diminish the quality of the product – it just helps fund this site so we can keep providing information to you free of charge.
My unusual symptoms are likely linked to some genetic risk factors I have.
The Gene Food site revealed the probable culprit behind my strange symptoms: I likely have a condition called histamine intolerance.
I decided to upload my raw DNA file from Ancestry.com to Gene Food to see if I have any genetic markers (also commonly referred to as “SNPs”, “risk alleles” or “variants”) for histamine issues.
Two days after placing my order, I received my report.
As it turns out, I do have risk alleles for histamine intolerance (and a few other things I will talk about later in this article).
Here’s a screenshot from my custom nutrition plan from Gene Food:
Now, histamine intolerance is a complex issue that deserves its own article (and I am planning to write one about it very soon), but, long story short…coffee and tea (and many other foods and drinks) can block an enzyme called Diamine Oxidase (DAO for short). DAO plays a role in histamine clearance. If DAO is blocked, histamine can build up in the body and cause uncomfortable symptoms.
As you can see in the image above, I carry one copy of the risk allele for AOC1 (as indicated by the yellow +/- box). According to Gene Food’s AOC1 page:
The risk ‘T’ allele of C47T in the AOC1 gene is associated with reduced DAO activity and histamine intolerance. For those carrying a single copy of the risk ‘T’ allele, DAO activity was reduced. Whereas for those carrying two copies of the ‘T’ allele DAO activity and expression was reduced. This suggests that the ‘T’ allele is associated with reduced expression of DAO rather than changes in its activity.
Therefore, those carrying the ‘T’ allele of C47T may be at risk of developing symptoms associated with histamine intolerance such as anxiety, body temperature issues, diarrhea, headaches, low blood pressure, flushing along with inflammation and irritation.
And, as you can see in the screenshot above, I have TWO copies of the risk allele for HNMT (as indicated by the red +/+ box). Gene Food’s HNMT page explains what this means:
Histamine N-methyltransferase (HNMT) is an enzyme that breaks down histamine and is encoded for by the HNMT gene.
Histamine plays an important role in the immune response, in particular, allergic responses. In health, histamine is released from immune cells (known as mast cells) resident in the skin, gut or lungs when a pathogen or allergen is detected. Histamine then generates three standard physiological responses:
Firstly, blood vessels are dilated to allow other immune cells to quickly reach the area where the pathogen was detected.
Secondly, smooth muscle contracts, which is thought to be a protective measure limiting other pathogens entering the body.
Finally, mucus-secreting cells are stimulated, for example in the nose or gut, to protect against further pathogens reaching tissue. In health, histamine is then quickly degraded by HNMT and the immune system clears the pathogen.
As its name suggests HNMT functions by transferring a methyl group onto histamine, inhibiting its function; with HNMT using S-adenosyl-L-methionine (SAM) as a methyl donor. This inhibited histamine can then be excreted from the body.
There is one SNP in the HNMT gene which is associated with poor health outcomes, rs11558538 or C314T.
DAO and HNMT are enzymes that break down (or metabolize) histamine. So, it appears that sometimes when I drink coffee, DAO and HNMT are blocked from doing their jobs, which in turn leads to unpleasant symptoms related to a buildup of histamine in my body. I say sometimes because histamine levels in the body can fluctuate quite a bit.
Since learning about histamine intolerance and my genetic risk factors, I’ve stopped consuming coffee before having citrus fruit. Most of the time, this works – but I have found that sometimes even coffee alone causes what feels like a histamine intolerance reaction. In the article Caffeine Allergy & Coffee Intolerance: What You Need to Know, Dr. Tania Dempsey, a Mast Cell Activation Syndrome (MCAS) expert, explains the likely reason:
Coffee is high in histamine which can set off what looks like an allergic reaction but it doesn’t occur through the typical allergy mechanism. Instead, the histamine from the coffee causes an inflammatory reaction that can be quite severe in some people. Histamine can cause a variety of symptoms, many of which overlap with symptoms related to intolerance or allergy to coffee, such as hives, rashes, shortness of breath, palpitations, abdominal pain, and many more. Some people are more sensitive to the effects of histamine in food and many of them have a condition known as mast cell activation syndrome, which in itself can lead to an increase in the amount of histamine in the body.
That’s enough about histamine intolerance for now. I’ll write a more in-detail article about it soon.
Gene Food provides personalized nutrition recommendations.
I’ll share a little information from my custom nutrition plan shortly, but first I want to tell you more about Gene Food.
On the Gene Food Start Here page, the company founder describes its mission:
We created Gene Food as a launching off point for people on a mission to find what works best for them when it comes to health and nutrition.
You could almost think of us as the referee for the diet wars.
We don’t advocate for any one diet.
We don’t sell supplements.
Instead, we created an algorithm that divides people into 20 different diet types based on their genetics. While we recognize genetics aren’t the whole story, lifestyle plays a big role as well, we see genetics as the foundation upon which we can each build our own “wellness house.”
Here are a few excerpts from the About page:
For generations, Americans have ping-ponged back and forth between different fad diets. Each new wave of research brings with it a new way of eating. We’re told fat is dangerous, eat more whole grains. Now we’re in the midst of another movement towards fat, with a greater emphasis on the dangers of sugar. Some advocate for the exclusion of all plant foods in favor of a carnivore diet. Others tout the benefits of beans and whole plant foods as enhancing longevity. Book after book is published telling all Americans how to eat.
While the nutrition wars rage on, a new and growing body of science is teaching us that there is no one size fits all when it comes to diet.
Our mission at Gene Food is to anticipate an individual’s response to a given diet and then assign them to a diet type that will work for them.
Gene Food’s resident geneticist, Dr. Aaron Gardner, created a scoring system that places people into one of twenty dietary categories based on how well they metabolize fats, carbohydrates, sugars, histamine, dairy and more. Individuals that are more likely to fall into the 107% increase in bad cholesterol group we saw in the Retterstøl study are assigned to a diet type that is more plant-based. By contrast, individuals estimated to have greater ability to deal with a higher saturated fat diet are placed in a diet type that allows for a greater percentage of calories to come from fat. In addition to the broad diet categories, Gene Food’s system scores people for micronutrient balance, sterol absorption, LDL, genes, methylation strength and more. Each gene we report on is assigned a Science Grade, which gives our readers and customers the opportunity to see what the state of the research is for a given gene. Gene with a higher Science Grade are backed by more research, lower Science Grades represent genes that are just starting to emerge. While we do not believe genetics are the only factor in evaluating dietary choices, we see them as a foundational tool to help people get started sifting through the mountain of marketing material aimed at funneling them to one of the popular dietary camps.
I have long believed that there is no one right diet (way of eating) for everyone and was so glad to come across the Gene Food site for this reason. Finally, science is getting closer to customizing nutrition! While nutrigenomics (broadly defined as the relationship between nutrients, diet, and gene expression) is an emerging field and there is still a LOT to be discovered, what is currently known is promising.
I learned a lot of other interesting things from my Gene Food report.
Gene Food has identified 20 distinct diet types. Based on my genetic data, my diet type is Nordic.
When you get your custom nutrition plan, you’ll be able to view it via a link Gene Food will send you by email, and you’ll also be able to download a more detailed PDF version. You’ll also see a button at the top of your plan that says “Download Meal Plan” – be sure to click on that because it is an in-depth PDF guide to eating according to your diet type.
Here is a screenshot of the beginning of my report, from the Overview section:
I found this VERY interesting because in early 2019 I switched from years of low-carbohydrate eating to a whole-food, plant-based way of eating, and have felt SO much better since I made the change. So, it looks like I was on the right path far before I’d even heard about Gene Food. On that note, remember that not all carbohydrate sources are created equal. For more on how to choose good carb sources, please see What are good carbs? A new study provides answers.
Clearly, low-carb high-fat diets truly are NOT right for everyone.
Neither are ketogenic diets, on that note:
Nordics likely don’t have the fat metabolism genes to pull off a Ketogenic diet.
In fact, for some people, high fat intake can be quite dangerous.
Why is dietary fat intake a concern for some genotypes, including those who are assigned the Nordic way-of-eating?
My report explains:
You don’t need to be on a low-fat diet, but should limit saturated fat and processed omega 6 rich fats like vegetable oils.
Analysis of your SNPs has suggested that a Nordic diet will prove beneficial for your general wellbeing. This diet type is characterized by a slightly lower overall fat intake, with an associated increase in carbohydrates, omega 3 rich proteins and plant proteins. Because you fall into the middle of our fat analysis based on your genetics, a good way to determine whether you are eating a healthy level of fat is to have your blood work done regularly. Your doctor can measure markers like LDL-P, APOB, and LDL-C, all of which are indicators of increased risk for heart disease when out of range. Having said that, you should definitely avoid high fat diets.
Here’s a screenshot of my dietary fat recommendations:
My custom plan is 26 pages long and quite detailed – and very impressive and useful.
I have two copies of two risk alleles for lactose intolerance, which is not surprising – I have known I am lactose intolerant for years.
And, I have risk alleles for gluten intolerance – also not a surprise, since I was diagnosed with Celiac disease several years ago.
Some information on my report surprised me.
What I did not previously know was that I have MANY risk alleles for cardiovascular disease, high cholesterol, and type 2 diabetes. All of my bloodwork has always been normal, but my guess is that I’ve been dodging bullets all this time because I’ve always been good about eating healthfully. Discovering that I have so many risk alleles that relate to cholesterol and dietary fat (21 out of nearly 40 in these categories) was a bit alarming, to say the least! I was adopted as an infant and don’t know a lot about my biological parents’ health history, so this information is particularly valuable to me.
Thankfully, I have always been health-conscious and I am particularly glad I have been following a whole-food, plant-based diet for nearly a year. My nutrition plan does recommend that I eat some fish, but that is one thing I am not willing to do (personal preference). However, I do take algal oil.
I am not going to share more details from my report out of respect for Gene Food – the sample plans they provide on their website do not provide full information, so I feel I probably should not share ALL of my details (and, some are a bit personal anyway).
If you’d like to learn more about Gene Food or order a custom nutrition plan from them (which I highly recommend!), you can do so here: Custom Nutrition Plan. If you have not done an Ancestry or 23andme test, don’t worry – Gene Food has a test kit you can order.
Gene Food can help you cut through all the noise about different diets and give you actual data to work with, based on your own genetic markers.
If you decide to order a custom nutrition plan from them, please let us know in the comments!
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