It is fair to say that ZOE provides a pretty powerful tool when it comes to evaluating your metabolism. Through measures of blood sugar spikes, fat clearance, and gut microbiome, ZOE gives you a snapshot into how your body responds to food right now. The key thing here is that it is a snapshot, not the full picture. A DNA test can reveal the genetic architecture underneath that is contributing to these real-time responses: how your muscles are composed, how your brain is likely to age, how you respond to different training stimuli, and what nutrients your body finds harder to metabolise. 

Your DNA tells you the why and what you can do about mitigating these predispositions.

You’ve invested in understanding your body by taking a ZOE test, but have you been left with unanswered questions such as what can you actually change in the gym, or why your family history is still worrying you? Understanding your genetics can help provide these outputs which ZOE was not designed to.

What does ZOE measure?

ZOE is a personalised nutrition programme built around three biological measurements: your postprandial blood glucose response (how sharply your blood sugar rises after eating), your blood triglyceride clearance rate, and your gut microbiome composition. Using continuous glucose monitors, a fat-response test, and a stool sample, ZOE builds a picture of your individual metabolic responses to food - which differs substantially between people even when they eat identically.

The central insight ZOE delivers is that there is no universal healthy diet. A food that stabilises one person's blood sugar may spike another's. ZOE's personalised food scores reflect your measured responses, not generic nutritional guidelines.

But what does ZOE not tell you?

You and your friend have both completed ZOE - they have a low blood sugar spike, while you had a high one. What is causing this difference in response?

ZOE reflects on your current metabolic state - a state that will shift with changes in behaviour, diet, age, activity, stress and more. What it cannot show you is what sits beneath this metabolic state. This is where DNA testing can complement your ZOE results. It can help you gain valuable insight into what macronutrients you may be more sensitive to, how efficiently you absorb vitamins, how well your detox pathways may function and how well your body responds to hunger and satiety signals. This can help you refine your dietary choices further by looking at your whole picture!

For example, there are genetic variants that can influence whether you are more predisposed to overeating and weight gain from saturated fat intake. There are also genetic influences on the response to higher carbohydrate intake when following a calorie restricted diet for weight loss. Insight into your genetic predispositions plus the data from ZOE gives you a comprehensive overview of what dietary strategies may be optimal for you. 

What can a DNA test add that ZOE doesn’t cover?

While ZOE focuses on your gut and nutrition, a DNA test can provide a whole-body view of why your body is responding in certain ways. This provides you the toolkit to take proactive steps to live healthier for longer. 

Here at FitnessGenes, our one-time test opens up insights into multiple aspects of your biology such as blood sugar regulation, inflammation, vitamin and mineral absorption, hormone function, and more. This provides actionable recommendations of how you can optimise your training, diet, supplements, lifestyle, and behaviour to be your healthiest self. 

How can I use both sets of data together?

ZOE and DNA testing are not competing products as  they answer different questions. ZOE tells you how to eat now, based on how your body currently responds. Your DNA tells you the biological rules your body is operating under and they do not change regardless of what you eat, how you sleep, or how hard you train.

Nutrition: Use ZOE's food scores to guide meal choices based on your measured responses. Use your DNA to understand which nutrient variants may be driving those responses and to personalise your diet and supplementation strategy further.

Training: ZOE doesn't address how you should exercise. A DNA test gives you insight into your muscle fibre profile, recovery genetics, and injury risk markers that inform what types of training is likely to suit you best.

Longevity: Combining the data from ZOE and a DNA test can provide a complete toolkit into how to adapt your nutrition, lifestyle, and behaviours to benefit longevity. Live healthier for longer through informed, data-driven solutions. 

If you’ve already completed the ZOE test, you’re actually the perfect candidate for DNA testing. You’re already motivated; you are already proactive, curious and act with energy when it comes to being health-conscious. DNA testing is the natural next step. It deepens your understanding, sharpens your strategy, and gives you the “why” behind everything ZOE has shown you in that first step.

FAQs

I've already done ZOE - do I really need a DNA test as well?

Yes, if you want the full picture. ZOE tells you how your body responds to food today. A DNA test tells you the fixed genetic architecture driving those responses and adds information ZOE doesn't touch: your training genetics, long-term brain and disease risk, and supplement needs. They answer different questions and work better together.

Can a DNA test tell me what to eat, like ZOE does?

A DNA test informs nutritional strategy differently, through genetic variants that influence how you metabolise fats, carbohydrates, and specific micronutrients, not through direct measurement of your blood sugar or fat response. Together, DNA and metabolic data give you both the why and the what.

Can my ZOE or DNA results change over time?

ZOE results can change. Your gut microbiome, blood sugar responses, and fat metabolism shift with diet, weight, age, and lifestyle. Your DNA does not change. It is a fixed reference point that informs your biology for life, regardless of what your current metabolic state looks like.

How can a DNA test influence any advice from ZOE?

A DNA test may highlight genetic variants that affect how you handle certain macronutrients such as fats or carbohydrates, which may provide further insight into how you could sharpen and refine the dietary guidance given by ZOE. For example, a variant of the APOA2 gene can cause increased risks of overeating and weight gain with high saturated fat intake. If your ZOE advice suggests a high-fat diet would be best, you can use your genetic data to make sure your high-fat diet contains the right kinds of fats for your genetics.

‍What testing procedures do DNA tests use compared to ZOE?

ZOE previously offered testing for blood glucose and fat levels, and is now focused on stool samples for gut microbiome analysis. Our DNA test uses a saliva sample which involves spitting a small amount of saliva into a tube. This is much less invasive than the testing ZOE requires but opens the door to a large amount of data. At FitnessGenes, your one-time saliva sample will unlock over 180 reports on various aspects of your biology, along with access to new reports and updates.

Author

Geraldine Campbell, MSc is an exercise physiologist who has worked at FitnessGenes for over 10 years. The work underpinning FitnessGenes' US patent (US 10,621,499 B1) covers methods for generating personalised training and nutrition recommendations from genetic data.

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