From a genetic perspective, every human is different. So it seems plausible that a diet or exercise regimen that works for one person might not work for you. DNA testing kits promise to unlock your genetic code so that you can eat and exercise in the healthiest and most effective ways possible.
My goal with this article was to find out if DNA testing for health and fitness is really worth it. So I dove into this topic, did a lot of research, and took four DNA test kits to analyze my DNA.
Continue reading for answers to the following questions and more:
- Should you take a genetic test to find the best diet for you?
- What are the best DNA tests for fitness and nutrition?
- Can DNA testing really help you maximize your fitness levels?
Covered DNA Test Kits
What is DNA?
Deoxyribonucleic acid (DNA) molecules carry the building plan — or genetic instructions — for every cell in your body. It’s a plan that you inherited from your biological parents.
According to the human genome project, there are an estimated 20,000 to 25,000 protein-coding genes in the human body — a number that keeps fluctuating as new scientific methods are developed. Indeed, the very definition of what a gene is keeps changing.
Why I Decided to Take a DNA Test
I’ve always been fascinated by what my genetic predisposition could mean for my life, and by what (if any) control I have over that.
That’s why some people take genetic tests: to find out about their health risks and their relative likelihood of developing conditions like Alzheimer’s disease, breast cancer, liver disease, cystic fibrosis, sickle cell anemia, Huntington’s disease, heart disease and ovarian cancer (among many others).
Others don’t want to learn about their predisposition because you can’t unlearn that information. Take a test that shows you’re “high risk” for breast cancer and you might spend your life worrying about a disease you’ll never get. That can add a lot of unnecessary stress as you look for possible symptoms.
I don’t have any hereditary diseases in my family, as far as I know. So my goals in taking a DNA test were to get more insight into the diet and exercise aspects of my genetic code, and to take cues on how to improve my diet and physical performance.
What You Learn From a DNA Fitness and Diet Test
When DNA testing companies started offering affordable at-home tests, their primary focus was to provide you with more data and information about your ancestry and traits.
A few years ago, a buddy of mine signed up for 23andMe* to find out about his ancestry. While the results weren’t life-altering, it was fascinating to learn how much European, Asian and African DNA he had inside of him.
As the industry and the science behind those DNA tests evolved, companies started adding health and wellness reports.
For example, DNA test kit manufacturers claim that your genetic makeup has a strong influence on your health and well-being, and thus that you should make lifestyle choices based on it.
How At-Home Tests Work
Almost every DNA test kit I’ve read about, including the ones I took, require you to obtain a sample of your cells from the inside of your cheeks by using a cotton swab. Depending on the type of test, you might also need to submit a saliva sample.
It’s entirely painless and non-invasive, and takes only a few minutes. Once completed, you stick the swab into a pre-labeled envelope and send it to the lab. Once your test reports are ready, you’ll get notified in the mail or via email, depending on the service.
How DNA Impacts Your Health and Fitness
Your DNA can have a significant impact on your health and wellness.
For example, if one of your parents has been diagnosed with Huntington’s disease — a progressive brain disorder — you have a 50% chance of having inherited that disorder.
Besides providing insight into your carrier status for hereditary diseases, your DNA can also influence other areas of your life related to your metabolism, the likelihood of food intolerance or allergies, and more.
The DNA tests I took provided me with information about how my metabolism works, if I’m more likely to respond to strength or high-intensity training, if I have any potential issues with absorbing certain micronutrients (i.e., vitamins or minerals) or if my skin is more or less sensitive to sun exposure.
However, it’s important to understand that not all test results are created equal — at least as far as scientific certainty is concerned.
For example, there is sufficient scientific evidence to suggest that people who carry the apolipoprotein E (APOE) gene have an increased risk of developing late-onset Alzheimer’s disease.
By comparison, nutrigenetics — the science of studying the relationship between the human genome, nutrition and health — is in its infancy, and test results are often based on preliminary scientific studies or statistical correlation.
For example, my genetic profile indicates that my utilization of fat is low and that I might be sensitive to too much total fat and/or too much saturated fat in my diet.
That’s funny, considering that I’m on a ketogenic paleo diet and >80% of my daily calories come from fat. What’s more, I feel great and my blood work and body composition reflect that.
My point is, just because there’s a statistical correlation between certain genes and certain dietary implications, that doesn’t necessarily mean that you’re affected and should blindly follow the recommendations of the test report.
How Your Lifestyle Can Change Your DNA
I was long under the impression that it’s impossible for a person to change their genetics. That’s a common belief, but recent scientific research suggests that while you can’t change your genetic code, your lifestyle can influence how your genes are expressed — it’s called epigenetics.
Vitamin D alone can influence the expression of 900 genes!
That means that just because you inherited the APOE gene described previously (for example), you’re not necessarily guaranteed to develop Alzheimer’s disease — especially if you follow a healthy dietary lifestyle that prevents your brain from developing issues with its glucose metabolism, which is the potential root cause of the disease.
What’s more, according to Dr. Perlmutter (a neurologist and proponent of high-fat low-carb eating), 90% of the genes that deal with health and resist disease are influenced by what we eat.
Epigenetics — the study of changes in organisms caused by modification of gene expression — is a hot topic among scientists right now. The takeaway is that our DNA is plastic and malleable, and you can directly influence whether or not individual genes activate or deactivate through your lifestyle. That’s called gene expression.
Keep that in mind when you try to make sense of any DNA test report and the accompanying recommendations.
My Experience With DNA Fitness Testing
While attending the Paleo f(x)* trade show in Austin, TX, I learned about Fit DNA RX*. The company specializes in food, exercise, nutrients and lifestyle — as far as DNA testing is concerned — and I decided to sign up.
Fit DNA RX offers several testing kits, including:
- Fit RX*: Learn how your body responds to nutrition and exercise.
- Elevate RX*: Performance-based assessment of how your body responds to exercise and training.
- Nourish RX*: In-depth analysis of how your body absorbs nutrients at a cellular level.
- Extend RX*: Provides insight into how your body ages according to your DNA.
- Ultimate RX*: A combination of all four DNA tests.
I took the Ultimate RX test and thus got four individual reports that showed some overlapping information.
If you want to get a PDF copy of my reports — so you can see what’s in there — submit your email address below and I’ll send you a download link.
If you don’t want to read through the full reports, below are the key findings from each of the four test kits I took.
Weight Loss and Exercise
Weight Loss Tendency
Your genetic profile indicates that your weight loss ability is BELOW AVERAGE. You may lose slightly less weight or body fat than expected from a lifestyle intervention.
So make sure to choose a well-designed plan and employ strategies to stick with it for the long term.
I’ve never struggled with managing my weight. But looking at photos from 2008-2012, I can tell that I gained some weight after coming to the U.S. and assuming a Standard American Diet (SAD).
Fat Loss Response to Cardio
Your genetic profile indicates that your fat loss response to cardio exercise 3 days per week while working out at a moderate-to-high intensity is LOW.
This does not mean that you cannot lose fat from this amount of cardio, but your fat loss may be minimal. You are likely to get optimal fat loss by exercising more. Aim for at least 200 to 300 minutes per week.
I do CrossFit 5 or 6 times per week, and I supplement my exercise regimen with a spinning bike I use for high-intensity interval training.
Fitness Response to Cardio
Your genetic profile indicates that your fitness response to moderate-to-high-intensity cardio is BELOW AVERAGE.
You may be less likely to experience optimal cardiovascular fitness improvements from high-intensity cardio compared to others with a more favorable genotype.
This does not mean that you will not improve your fitness. You can. But you will likely see greater gains from longer, moderate-intensity workouts. Or you may benefit from endurance-based resistance workouts such as circuit training and power training.
I’ve definitely seen dramatic improvements in my cardiovascular capacity by not going “all in” at every workout. Instead, I work out at a low heart rate a few times a week — it’s called heart rate training.
Body Composition Response to Strength Training
Your genetic profile indicates that your body composition response to strength training is ENHANCED. In addition to strength improvements, you are more likely to see reductions in your body fat percentage from weight training.
Make sure to include resistance exercise 2 to 3 times a week.
HDL Response to Cardio
Your genetic profile indicates that your HDL response to cardio is ENHANCED. For optimal results, do cardio 5 or more days per week.
Based on blood tests I’ve had done over the past few years, diet was the most influential factor on my HDL scores.
Insulin Sensitivity Response to Cardio
Your genetic profile indicates that your insulin sensitivity response to cardio is ENHANCED.
Performing 3 or more days of cardio per week should improve your glucose uptake. You can optimize these effects by working out more than 3 days per week and including resistance training in your workouts.
I’ve never tested my insulin and blood glucose levels with different types of workouts, but I’ll do that when I get a chance and report back on it!
Grip Strength/Muscular Fitness
Your genetic profile indicates that you are likely to have ABOVE AVERAGE hand grip/intrinsic muscular strength.
You are genetically predisposed to perform above average on tests of grip strength as well as tests of general muscular strength and endurance.
I have noticed during CrossFit workouts that I have a relatively strong grip. For example, I recently won a contest in my gym by hanging from a pull-up bar for two minutes without letting go.
Food and Nutrients
Your genetic profile indicates that your utilization of fat is LOW . You may be sensitive to too much total fat and/or too much saturated fat in your diet.
If you are dieting, or reducing calories to create a negative energy balance, you may experience less weight loss with a higher-fat diet. Aim for a low total fat and low saturated fat, reduced-calorie diet.
Most of what I eat as part of my ketogenic paleo diet is fat. In fact, approximately 70-90% of my caloric intake comes from fat each day. I have not seen any evidence suggesting that my fat utilization is low.
Your genetic profile indicates that your utilization of complex carbohydrates is ENHANCED . This suggests that you may experience the best weight loss results if you follow a diet that is higher in complex carbohydrates and lower in fat.
This means that you should focus on including more whole, unprocessed plant foods in your diet, including beans, whole grains, nuts, seeds, fruits and vegetables.
Use added oils sparingly. Instead of sautéing vegetables in olive oil, for example, use vegetable broth.
Since starting a ketogenic diet, I’ve tried to figure out what amount of carbs would kick me out of ketosis.
One day, I ate a whole pizza with a whopping 160 grams of carbs. I measured my blood glucose and ketone levels two hours and 10 hours after eating the pizza. To my surprise, I was still in ketosis at each test. So, evidently, my body utilizes carbs efficiently.
Your genetic profile indicates that you are likely to have a SLOW rate of caffeine metabolism.
This means you are not likely to benefit from the stimulant’s ergogenic benefits as much as someone with a normal rate of caffeine metabolism and caffeine use may actually be detrimental to your health.
I totally agree with that. That’s why I stop drinking coffee at noon. If I have a cup of coffee at 2 or 3 p.m., it negatively impacts my sleep.
Vitamin B6 Tendency
Your genetic profile indicates that your response is LOW, indicating that you are at risk for having low levels of Vitamin B6.
Check your status by asking your doctor for a blood test. Eat enough B6-rich foods and supplement if you are low.
I eat lots of avocado, spinach and tuna — all good sources of Vitamin B6. So I’m not concerned about having low Vitamin B6 levels.
Vitamin B12 Tendency
Your genetic profile indicates that your response is LOW. This suggests that your blood levels of Vitamin B12 may be at the low end of the acceptable range.
Ask your doctor to check your Vitamin B12 levels and get them checked on a regular basis. If your levels are low, in addition to getting more Vitamin B12 through foods, you may wish to supplement.
I eat lots of meat and pastured eggs — all good sources of Vitamin B12. So I’m not concerned about having low Vitamin B12 levels.
Vitamin D Tendency
Your genetic profile indicates that your response is BELOW AVERAGE, so your levels of Vitamin D may be low and possibly deficient.
Get your blood tested for Vitamin D. If your levels are low, increase your sun exposure and add more Vitamin D-rich foods or supplements.
I eat a lot of salmon, sardines and pastured eggs — all good sources of Vitamin D. Plus, I spend sufficient time under the sun — around 20 minutes every day, either by sitting shirtless outside in the afternoon or by biking to CrossFit without a shirt. So I’m not concerned about having low Vitamin D levels.
Look and Feel
Your genetic profile indicates that you are inclined to have an UNFAVORABLE level of sun sensitivity.
We recommend that you protect your skin from short term burning and the long term health risk for skin cancer by taking extra steps to guard your skin against UV ray exposure.
I burn easily, which is why I put a mineral-based sunscreen on my face every morning.
Your genetic profile indicates that you are likely to have a BELOW AVERAGE level of susceptibility to stretch marks.
You can reduce your risk even further during high risk times (such as pregnancy) by practicing healthy diet, exercise and lifestyle habits to maintain healthy skin elasticity.
When I was a professional athlete in my early 20s and I gained muscle mass, my skin tore near my armpits and my groin, leaving me with stretch marks. I only gained 10-15 pounds during that time, so I didn’t expect that to result in stretch marks. So, I would challenge the above assessment.
Intrinsic Motivation to Exercise
Your genetic profile indicates that you are MORE LIKELY to have intrinsic motivation to exercise.
You will be more inclined to start and maintain an exercise routine without the need for external motivation or rewards. So be sure to build time into your schedule to enjoy at least 150 minutes of activity a week.
I’m driven and highly motivated — both inside and outside of the gym.
Addictive Behavior/Stimulus Control
Your genetic profile indicates that you are LESS LIKELY to have an addictive behavior personality type.
You’re less susceptible to overindulging in highly stimulating behaviors like excess alcohol or drug use, overeating or to smoke.
That’s good news as cigarette smoking is the most common preventable cause of many diseases, including heart disease and cancer and contributes to about 6 million deaths a year world-wide.
I’ve never smoked or used drugs — but I do like my glass of red wine every night.
Your genetic profile indicates that you may be likely to get an ABOVE AVERAGE amount of sleep per night. Since the average American sleeps just 6.8 hours of sleep a night, that’s good news.
Because many lifestyle, diet, and behavior factors impact your sleep duration, you’ll be more likely to maximize your genetic potential and to consistently get the recommended 7 to 8 hours of restorative sleep each night if you implement habits that are conducive to good sleep.
I get at least seven hours of quality sleep every night. But that wasn’t always the case.
A few years ago, I changed my sleeping patterns by becoming incredibly protective of my sleep. I go to bed every night around 9 p.m. and get up shortly after 5 a.m. — every day. I’d argue that my good sleep is more a product of behavior than genetic predisposition.
Your genetic profile indicates you are likely to consume a NORMAL amount of sugar.
You’ll consume even healthier amounts—and avoid the negative health consequences related to eating too much sugar—by raising your awareness of what foods contain added sugar and how much you presently consume, so you can choose better alternatives.
I can assure you that I consume below average amounts of sugar. In fact, I virtually avoid all food that has sugar, with the exception of some fruits.
Age Related Hearing Loss
Your genetic profile indicates that you have an INCREASED risk for age-related hearing loss.
We recommend that you take extra precautions to protect your ears, maintain good general health and avoid damage and health conditions that can contribute to hearing loss over time.
So far my hearing is excellent, but I’ll keep an eye (or ear) on that.
Your genetic profile indicates that you are inclined to have ABOVE AVERAGE systemic inflammation levels.
You can lower your CRP levels and avoid inflammation-related chronic diseases by practicing healthy diet, exercise and lifestyle behaviors.
Reducing inflammation and the risk of developing a chronic disease is the primary reason why I adopted a ketogenic/paleo lifestyle.
Triglyceride Response to Cardio
Your genetic profile indicates that you are at risk for a BELOW AVERAGE triglyceride response to regular cardiovascular exercise.
If a blood test shows your triglyceride levels are elevated, we recommend that you continue getting at least 150 minutes per week of physical activity most days a week for good general health and employ other exercise, lifestyle and/or medical interventions to reduce them to healthy levels.
My triglyceride levels have come down from 102 to 38 since I started with the paleo diet. I expect them to be even lower this year after having also started a ketogenic diet.
Your genetic profile indicates that you are inclined to have BELOW AVERAGE blood levels of calcium.
You can help keep your skeleton strong by eating a bone-building diet, getting regular exercise and practicing other skeleton saving behaviors.
I recently had a body composition scan performed to determine my body fat and bone density. Despite the fact that I don’t eat a lot of dairy (because it’s not paleo) I had excellent bone density.
Dietary Choline Tendency
Your genetic profile indicates that you have an INCREASED sensitivity to a low-choline diet.
Since you are more likely to suffer organ dysfunction and muscle damage should your choline intake fall below recommended levels, you should make it a priority to eat plenty of choline-rich foods for optimum cell, nerve and organ function.
I eat a lot of eggs, seafood, poultry and broccoli — all good sources of choline.
Should You Take a Genetic Test?
I strongly believe that you should learn as much as you possibly can about your body and what impact food, exercise and lifestyle can have on it.
Your DNA is your DNA, whether you like it or not. It might be scary to learn that you have a heightened likelihood of developing a particular disease or disorder, but knowing that information gives you the ability to take steps to mitigate those health risks.
Specifically, understanding your genetic makeup can help you to fine-tune your approach to diet and exercise, which can not only improve your overall wellness but also actively change your gene expression.
However, I don’t recommend that you build a diet or exercise regimen solely based on the findings of a DNA test. In fact, a randomized clinical trial from 2018 concluded that there was no significant difference in weight loss between overweight participants following a “DNA diet” and those on diets that weren’t based on the participants’ genotype.
- Carefully read the test results
- Think about how they apply to your lifestyle
- Get additional tests (blood work), if necessary
- Change your lifestyle solely based on test results
- Blindly adopt a low-fat high-carb diet
- Stop doing cardio or strength training
- Expect dramatic results by implementing the recommendations from the test
If I knew nothing about food, fitness and the human metabolism — and then decided to blindly follow the advice provided by my DNA test reports — I’d be on a low-fat high-carb diet. That’s exactly the opposite of what evolution has taught to be the most effective diet for weight loss.
Plus, your genetic makeup doesn’t give you much indication of gene expression. Just because I have the NBPF3 gene, and thus have a genetic predisposition to lower Vitamin B12 levels, that doesn’t mean that this gene is active (expressed).
I encourage you to get your DNA tested so that you have a baseline. Just don’t freak out if you see low or below average results. Instead, get a full health screening from a healthcare professional you trust, and talk about the results of your test. If there’s anything noteworthy or concerning, you might be prompted to get some extra blood work done at your next annual physical.
That said, you can also implement the small (positive) tweaks suggested by your data. For example, I’ll make it a point to get some of the vitamins and minerals noted to make sure that I have adequate levels. I’ll also double down on sun screen and lower my caffeine intake.
At the same time, I’ll continue with my ketogenic paleo diet and my functional fitness regimen — both of which have transformed my body and have put me on a better path towards health.
Frequently Asked Questions
I’d recommend against that. There is little evidence to suggest that a diet based on your individual genotype is better than a healthy diet that’s based on broader scientific evidence and 2.6 million years of human evolution.
I don’t argue that there’s no place for personalized nutrition. I just don’t think personalized nutrition is the most important thing you should worry about. The key is to establish a basic nutrition plan that you can turn into a lifestyle, and worry about health tests later.
If you’re looking for a diet that you can turn into a lifestyle, check out this ultimate guide on healthy eating and my guide to the ketogenic paleo diet.
There are numerous companies available these days. I’ve used Fit DNA RX* and the test results I show in this article are based on that. Another popular choice with FDA-approved testing methods is 23andMe.
If you’ve done the 23andMe test already and would like to give Fit DNA RX a try, you’ll get a discount, and Fit DNA RX can reuse the samples you gave to 23andMe — no need to take another swab.
23andMe also provides some interesting — if not particularly valuable — data on ancestry and ethnicities.
A DNA fitness test can give you statistical insight into how your genome or genetic makeup might influence your fitness, athletic performance, and overall wellness.
The premise of the DNA diet is that everybody is different and a one-size-fits-all diet doesn’t work. While I agree that we’re all different, there is no scientific evidence that your DNA can give you insight into what foods you should eat or avoid.
Instead, I highly recommend the diet that humans have evolved with over the course of 2.6 million years. That’s a ketogenic paleo diet, paired with intermittent fasting. From there, you can see how your body reacts to individual foods and make adjustments as you go.
Sleep is a major contributor to the health of the bacteria in your gut. Those bacteria, in turn, can directly influence the expression of your genes. As a result, the quality of sleep you get, and other lifestyle factors (such as diet) directly influence which of your genes become active.
Genetic testing reveals what genes you have and how those genes statistically correlate with certain traits, such as the rate at which you metabolize caffeine or whether you have a particular food intolerance. Unfortunately, home DNA test kits don’t reveal which of the genes you have are active.
DNA testing can, potentially, guide you in the right direction or give you a clue about what to pay attention to in your workout plan. For example, my test results showed that I might have difficulty improving my cardiovascular capacity (VO2max) through HIIT.
I can take that as a clue and experiment with other types of workouts, such as heart rate training, to compensate for my physical limitations.
However, I wouldn’t recommend that you blindly structure your training based on a DNA test, without working with a knowledgable coach and listening to your body.
That depends on how you define “work!” A DNA test can certainly give you insight into your genetic makeup and how that correlates to certain fitness and dietary traits.
However, gene expression is heavily influenced by your lifestyle and, unfortunately, the DNA tests discussed in this article don’t tell you whether a certain gene in your body is active or not.
While the process of sampling DNA of hair is scientifically sound to identify chemical residue of heavy metals, food and other things, there is no scientific evidence that such test results reveal food sensitivities. In other words, you might get a false positive that could lead to removing foods from your diet that aren’t causing any issues.
DNA testing may be able to help you lose weight, if utilized the right way. But it’s much more effective to focus on quality sleep, exercise, and a healthy diet that’s low in processed carbs and high in healthy fats and protein.
Conclusion – DNA Testing for Health and Fitness
Unlike food sensitivity tests — which are entirely unreliable and can be downright misleading — DNA testing is a scientifically sound method to give you insight into your genome and how your family history might impact your health and disease risk.
However, the interpretation of the results are often based on statistical correlation and observational studies. But just because others who have similar genes show a certain trait, that doesn’t mean you do too.
DNA testing for health and well-being is a fascinating concept that’s still in its infancy. We have to learn a lot more before we can make informed and life-changing decisions based solely on DNA test results.
So keep that in mind if you decide to take such a test to improve your athletic performance or overall wellness. The good news is that once you know about your genetic makeup, you can always apply the latest scientific research to better interpret the results.
For example, based on today’s research, having the PEMT gene is correlated with an increased sensitivity to a low-choline diet. Maybe in 10 years, we’ll know for certain that people with PEMT have to increase their intake in dietary choline — or even take supplements.
I found my test results fascinating and I could certainly identify with some of the findings. Others didn’t seem to match. That could be because the associated genes aren’t active, or because my lifestyle is suppressing them.
What’s your take on DNA testing for health and fitness? Have you taken a test? If so, do you agree with the findings?