We’ve never been more in tune with our vital health signs as a society. Wearables, step trackers, glucose monitors, sleep apps and at-home testing now give us access to a constant stream of information about our bodies. But is that data actually helping us move forward?
Without the right context, health data can confuse more than it clarifies. Numbers are only useful when you understand what they mean, how they relate to your symptoms, and what to do next. In this discussion, Dr Sabine Donnai and Jonathan Wreaves explore the metrics that matter, the danger of tracking the wrong things, and how to turn raw health data into meaningful action.
Watch our discussion with Dr. Sabine Donnai and Jonathan Wreaves.
We are not suffering from a lack of data. We are suffering from a lack of understanding.
We are living in a world now where there is a huge volume of data, almost an excess of data, if we think about the wearables people have, the sleep trackers, the glucose trackers and the access to lab testing. People don’t know what to do with this data. It’s confusing.
Yeah, and that’s exactly what we’re seeing. We have people coming in with piles and piles of data, sometimes years’ worth, and we say: “What has this taught you?”
Then you have the silence.
Has it made you wiser? Has it made you change your habits? How has this impacted your health, your lifestyle, or have you understood anything from this?
The answer, in the main, is: “I’ve got the data. What do I do with it, and how do I make this relevant to me?”
Is more data better? No, it’s relevant data that is better.
That’s where, I guess, we come in, thankfully. Of all the data points we can measure now, which do you feel have been most useful for us to gather from our clients, so we can start tracking and influencing?
I think there are clearly some key elements, but it also depends on what the client is presenting from a symptom point of view. You get some people who run and do their own testing to investigate a certain symptom, but we know they’re going down the wrong path in the first place.
We often see it with digestive symptoms. People run food intolerance testing, when actually they should be looking at bacterial overgrowth testing.
We also have people measuring their sleep, and they’ve been doing so for many months, when actually it’s not a sleep quality issue. It’s an obstructive sleep apnoea diagnosis that they’ve missed. So, the relevant testing for the symptoms is crucial.
Having said that, there is clearly some data that we find offers huge value.
We know tracking cardiovascular fitness, or VO2 max, is critical because it correlates very strongly with current and future health.
We know that tracking markers related to metabolic function is important. Insulin, for example, is not commonly measured when people look at glucose markers or glucose sensors, and that is a mistake people often make.
We know tracking lean tissue and muscle mass is critical.
And how do people do that? How do they track that?
Most people will say, “I’ve got some scales, and I’ve put on weight or I’ve lost weight.” Then we say, that’s not the data point you really want to track.
The weight is almost irrelevant.
Exactly. For a population, there is some use, but for an individual, that data is irrelevant. We need to break that down and see, of that weight, how much is fat tissue and how much is lean muscle tissue?
Where is that tissue distributed? That can have a significant impact depending on where it is within the body.
Yes, that can be done at home, but often it’s done inaccurately on poor-quality devices.
That’s what we’re seeing. We’re seeing what we call the “skinny fat” profile. People look very slim, and they’re not overweight in terms of total weight, but they have far too much body fat.
So, tracking on its own is only relevant if you know what to track and if you know how to interpret it.
Often, it’s the combination of a multifactorial approach, where you’re looking at the whole person with relevant different types of testing, rather than acting on one test or not understanding that test.
There’s also the danger that the more data and testing you do, the more you disengage someone because they can’t relate to it. It becomes overwhelming.
Our job is really to focus on the key interventions that we can help coach someone through, so they can change behaviour and stick to it.
The second part is identifying the key elements people need to focus on. If someone has 50 interventions or 50 elements they need to start working on, no one is going to do all 50. But if we say, “Look, these two or three are actually going to give you the biggest reward for your symptoms and what you’re trying to achieve,” that becomes far more useful.
The skill and the expertise is knowing which ones to focus on, having chosen the right data in the first place and being able to interpret that data.
So really, having all this data is like having a map without a compass: plenty of information, but no direction.
So nicely said, Johnny.
Key extracts
- We are not suffering from a lack of health data, but from a lack of understanding.
- Wearables and trackers can be useful, but only when the right metrics are measured and interpreted properly.
- More data is not always better. Relevant data is what makes the difference.
- Symptoms need the right type of testing, otherwise people can end up investigating the wrong issue.
- Metrics such as VO2 max, metabolic function, insulin, lean tissue and muscle mass can offer valuable insight into current and future health.
- Expert interpretation helps turn overwhelming data into a focused, personalised health strategy.
We have more health data than ever, but less clarity
Modern health technology has changed the way we understand our bodies. Many people now track their steps, sleep, heart rate, blood glucose, calories, recovery scores and body weight every day.
On the surface, this looks like progress. More information should mean better decisions. But as the video explains, the reality is more complicated.
Many people arrive with months, or even years, of health data, but still do not know what that data has taught them. They may have tracked their sleep without improving their energy. They may have monitored glucose without understanding insulin. They may have collected test results without knowing how those markers connect to their symptoms, habits or long-term health.
That is the central problem: data alone does not create wisdom.
If health data does not help you understand your body, change your behaviour or make better decisions, it can become noise. It may even create anxiety, confusion or disengagement.
A number on a dashboard does not automatically tell you what to do. A sleep score does not always explain why you feel tired. A normal glucose reading does not necessarily mean your metabolic health is optimised. A change in body weight does not reveal whether you have lost fat, muscle or fluid.
The value lies in interpretation.
This is where expert guidance becomes essential. The right clinician or health specialist can look beyond isolated numbers and ask better questions:
- What symptoms are you experiencing?
- Which tests are actually relevant?
- What patterns are emerging across different markers?
- Which findings matter most?
- What actions will have the biggest impact?
Without that context, even a large volume of data can leave people stuck.
“We are not suffering from a lack of data. We are suffering from a lack of understanding.”
Dr Sabine Donnai, Viavi Founder & Chief Executive
More Data Is Not Always Better
One of the key themes in the discussion is that more data does not automatically mean better health insight. Relevant data is what matters.
This distinction is important because many people assume that testing more things will create a clearer picture. In reality, excessive or poorly chosen data can make the picture harder to understand.
For example, the video explains how someone with digestive symptoms might pursue food intolerance testing, when the more relevant investigation may be bacterial overgrowth testing. Similarly, someone may track sleep quality for months, when the underlying issue could be obstructive sleep apnoea.
In both cases, the person is collecting data, but not necessarily the right data.
That can lead to wasted time, missed diagnoses and frustration. It can also cause people to focus on surface-level metrics while overlooking the deeper issue.
The lesson is simple: the most useful health data is not always the easiest data to collect. It is the data that is most relevant to the individual, their symptoms and their goals.
The Metrics That Matter Most
Although health data should always be personalised, the video highlights several areas that can offer significant value when measured and interpreted properly.
VO2 Max and Cardiovascular Fitness
VO2 max is one of the most important indicators of cardiorespiratory fitness. It reflects how efficiently your body can use oxygen during physical activity, involving your heart, lungs, blood vessels and muscles.
Tracking VO2 max can help identify whether your fitness is supporting your health goals or whether it needs focused improvement.
Metabolic Function and Insulin
Many people now use glucose monitors or track blood sugar markers, but the video makes an important point: glucose alone does not tell the whole story.
Insulin is often missed, despite being highly relevant to metabolic health. A person may focus on glucose spikes while overlooking how hard the body is working to control those glucose levels.
Lean Tissue and Muscle Mass
Weight is one of the most commonly tracked health metrics, but it is also one of the least specific.
Body weight alone is often not the data point people should focus on. For an individual, total weight can be misleading because it does not show what that weight is made of.
A person may lose weight but also lose valuable muscle. Another person may appear slim but carry too much body fat and too little lean tissue. This is sometimes described as being “skinny fat”, where external appearance does not reflect internal body composition.
Interpretation Is Everything
Tracking is only relevant if you know what to track and how to interpret it.
This is where many people become overwhelmed. A wearable might show dozens of daily metrics. A private blood test may return pages of results. A body composition scan may include numbers that are difficult to understand without explanation.
When people are given too much information without guidance, they can disengage. Instead of feeling empowered, they feel confused.
That is why the role of expert interpretation is so important. The aim should not be to give someone 50 things to fix. Very few people can act on that. The aim should be to identify the two or three changes that will deliver the greatest benefit based on their symptoms, goals and health profile.
This is the difference between information and strategy.
“Having all this data is like having a map without a compass. Plenty of information, but no direction.”
Jonathan Wreaves, Viavi Chief Clinical Officer
A map can be valuable, but only if you know where you are, where you are trying to go, and which direction to take.
Health data works in the same way. It can show patterns, risks and opportunities, but it needs interpretation to become useful.
Without context, data can leave people wandering between numbers, trends and test results without a clear next step. With the right guidance, that same data can become a route map for better health.
Turn Health Data Into Action With Viavi
At Viavi, health data is not treated as a collection of isolated numbers. It is used to build a deeper understanding of the whole person.
Through advanced diagnostics, expert clinical interpretation and personalised health planning, Viavi helps clients understand which metrics matter most for their body, symptoms and future health. The goal is not simply to gather more information. It is to make that information useful.
A Viavi Advanced Health Evaluation is designed to look beyond standard health checks. It can help assess key areas such as cardiovascular fitness, metabolic health, body composition, muscle mass, biomarkers, lifestyle factors and long-term risk.
This broader view is important because health is multifactorial. Sleep, stress, fitness, nutrition, hormones, metabolic function, inflammation and body composition can all influence how someone feels and performs. Looking at one marker in isolation may miss the bigger picture.
By combining relevant testing with expert interpretation, Viavi helps clients move from uncertainty to clarity.
If you are ready to move beyond tracking and start making informed decisions about your health, contact Viavi today to book your Advanced Health Evaluation.