In the past, monitoring blood sugar levels was something you only did if you were diabetic. My grandma was diagnosed with type 2 diabetes in her 50s, and I vividly remember her tracking her blood sugar levels by pricking her finger, squeezing a drop of blood onto a testing strip and inserting the strip into a little machine which sat on her kitchen table.
Thankfully, technology has since helped make the process less visceral. Now, with the introduction of continuous glucose monitors (or CGM for short), those with diabetes can track their glucose levels in real time without ever having to draw blood. And since most CGM sensors can be paired with a smartphone – via Bluetooth – everything is recorded in an app, so you can have a constant eye on your blood sugar levels at the click of a finger.
This technology, for those with type 2 diabetes, is nothing short of revolutionary. But that’s not the whole story....
As you might have gathered when looking at the little plastic circles adorning multiple upper arms in your gym, CGMs have been increasingly marketed to – and used by – people who aren’t diabetic.
People for whom blood sugar spikes and crashes don’t fall under the ‘medical emergency’ category, but who are hungry for more biometric data via which they can optimise their wellness.
Here’s everything you need to know about one of the newest – and buzziest – wearable product innovations out there.
What are continuous glucose monitors?
Continuous glucose monitors provide real-time monitoring of glucose levels (the sugar in your blood). These new continuous glucose monitors look like small patches which sit on the back of your arm and feature a tiny sensor (resembling a needle) that penetrates the skin and measures glucose levels.
This data is then sent to a smartphone, allowing users to constantly watch their glucose levels throughout the day, and alert you if your glucose levels are too high or too low.
So how does the science work?
Everyone’s glucose levels rise when you eat, as food is broken down into simple sugars to act as fuel to keep our bodies up and running.
When we eat, our bodies have to work to process the glucose we consume. Enzymes, with help from the pancreas, break down the food we eat, and our bodies tell the pancreas whether or not to release insulin to manage our rising glucose levels.
For people living with diabetes, the pancreas doesn’t produce the insulin needed and/or the body’s cells may not properly use the insulin being produced (which is why monitoring glucose is so important for diabetics).
‘People’s blood sugar response to different types of carbohydrate can vary quite significantly depending on metabolism, genetic make-up, stress levels, sleep patterns and even the microbes living in the gut,’ explains Rachel Hampson, nutritional therapist and vice-chair at the Institute for Optimum Nutrition.
A ‘spike’ is roughly defined by scientists as a sudden increase of more than 1.7mmol/L of glucose in your blood. A ‘crash’ is when the total amount of glucose in your bloodstream falls below 3.9mmol/L.
Who should actually be tracking their glucose?
Continuous glucose monitors are clearly indispensable for people with diabetes, but what about everyone else?
They can also be useful for people who are at risk of developing type 2 diabetes says Professor Tim Spector, co-founder of ZOE, the personalised nutrition company and author of Sunday Times best-selling books, Food for Life and Spoon Fed.
He describes how glucose monitors can provide real-time insights into how your body is responding to certain foods – as well as whether your blood glucose is above optimal range for long periods of time in the day.
‘People at risk of type 2 diabetes can use these insights to implement dietary and lifestyle changes to prevent incremental worsening of blood sugar levels over time,’ he explains. ‘This will help reduce the risk of developing insulin resistance and type 2 diabetes.’
But for everyone else, is knowing all the data about your glucose levels actually helpful?
‘The use of CGMs in people without diabetes is a growing field in disease prevention and personalised nutrition,’ says Prof Spector. ‘It can give a very useful insight into your metabolism, as blood sugar responses can vary greatly from person to person, even when they eat the same food.’
‘It’s important to remember, though, that it’s normal for blood sugar to rise after a meal,’ he caveats – speaking to a common gripe among those who are sceptical about CGM’s having much material benefit for the non-diabetic population.
‘The aim is not to flatline your blood sugar – instead, people should focus on eating in a way that avoids repeated, excessive spikes.’
Could wearing a CGM make me healthier?
To find out first-hand how informative wearing a continuous glucose monitor really is, I decided to test the Lingo wearable, a consumer bio wearable from Abbott – one of the largest manufacturers of CGMs.
While I do have a family history of diabetes (my grandma, as mentioned, had it, as do both of my uncles), I’m not overweight, or currently at risk of developing type 2 diabetes.
I tested the wearable for a month – when I felt great, I checked my glucose; when I felt awful, I checked my glucose; when I exercised or ate something, I checked my glucose (you get the gist...) Here, then, is how I got on...
The setup
The device comes pleasingly packaged in a neat box. I downloaded the Lingo app onto my phone, set up an account, and followed the simple instructions on how to apply my biosensor (which is about the size of a £2 coin) into my upper arm.
I must admit, the tiny probe hurt more than I was expecting it to – but it’s no more painful than a sharp pin prick since it barely pierces the arm. Perhaps it was more the clicking noise that accompanies the insertion that shocked me. The biosensor lasts for two weeks – so you don’t need to charge it or anything, then you remove it and pop a new one in.
On the home screen of the app, there are two numbers. The top number is your ‘live Lingo Count’ – the longer the glucose spike, the higher this number goes. The bottom number is your daily target or recommended ‘Lingo Count’. Below the numbers is a glucose graph, where you can see the spikes – and how many points they add to the count.
Within an hour I started seeing my real-time glucose data on the Lingo app and I already knew I was going to become obsessed with checking it.
After 24 hours
The first week is all about working out what your ‘baseline’ is, and seeing how your current eating habits affect your glucose levels. So, basically, just eat and exercise as you normally would and see how your body reacts via the spikes on your iPhone screen.
I ate a baked feta pasta dish for dinner on the first evening of wearing the monitor (a go-to mid-week meal made popular by TikTok) and my glucose levels spiked pretty much immediately (by +15 points on the Lingo app). My Weetabix and banana (plus coffee, of course) breakfast the following morning didn’t seem to have as dramatic a spike, but an hour-long reformer Pilates class at lunch sent it skyrocketing again.
I must confess, I think I checked my glucose level on the hour every hour during the first 24 hours of wearing it – even though, for the majority of the time, it just said ‘your glucose is steady’. It begged the question; could this obsession with tracking my health do more harm than good?
After a week
One week down, three to go. Somehow, according to the Lingo app, I successfully stayed under my benchmark target of 85 and spent my ‘Lingo counts’ throughout the day, which meant my new (personalised) target had been reduced to 55.
I tried to work out if there were any major patterns or themes, but – to be totally honest – all my data seemed a little conflicting. Avocado on toast, no spike. Homemade leek and potato soup, big spike. Three small glasses of prosecco on a Saturday night, no spike. HIIT workout, huge spike. Roast dinner with all the trimmings, no spike. Dark chocolate, spike.
The app tells me the next stage is all about focusing on my new target (55), lowering my glucose spikes and building healthier habits. It recommends making my midday break an active, healthy one with a short walk and water and really focusing on my meal when I eat – since minimising distractions can help you gauge how hungry you truly are.
After a fortnight
Two weeks in and this week I’ve managed to stay within my new target for four out of the seven days, so since my Lingo counts were, on average, under my target of 55, my recommended target has once again been reduced – this time to 45.
Have I managed to make sense of all the data? In all honesty, not really. Could I tell you why my body randomly has a glucose rollercoaster in the middle of the night? Nope. Do I understand how to flatten those glucose spikes? Sort of.
My app recommends including 10 minutes of movement after each meal to help keep my glucose steady, and this does make a noticeable difference. It also suggests thinking about how I can include more fibre into each meal and snack (since fibre can help reduce glucose spikes, and help you feel fuller for longer).
For me, when I ate ‘undressed carbs’ – that is carbs without accompanying fibre, fat or protein – my glucose levels sharply rose, and then steeply crashed (AKA a sugar crash).
Each biosensor only lasts two weeks, so in order to keep testing for the remainder of the month, I have the dreaded task of removing my current monitor and applying a new one. But it wasn’t as bad as I thought. You just slowly peel away the adhesive from your skin in one motion and it’s out.
After a month
As someone with a rather competitive edge, I’m ever so slightly ashamed to admit that during the month I spent testing this glucose monitor, I never actually made it out of the second ‘focus’ stage and into the final ‘evolve’ phase.
Why? Because in order to complete the focus level, you need to stay within your set target for five days a week, for two weeks in a row. And since I only managed to stay under target on four days on week two, it didn’t matter that I was within target for six days on week three, I had to remain in the focus stage for week four.
But you’re probably not that interested in my specific numbers and whether I spent most of my Lingo counts in the afternoon or evening. The question, I’m sure, you want to ask is if it’s any good, what I learned and whether it’s worth your hard-earned money...
My verdict
Is this technology groundbreaking? Absolutely. Is it really something we all need? Well, I can’t answer that for you. But, for me, I personally won’t be sticking with it long-term. That’s because wearing the monitor didn’t meaningfully change the way I ate or exercised.
And, on reflection, I guess that’s because – give or take – I’m someone who knows what my body needs (both food and movement-wise) to feel strong and healthy.
If, however, you’re someone right at the beginning of a health journey, I can see how these insights might be more valuable. Especially if you’ve become disconnected from which foods make you feel and function at your best.
And, of course, if your current body composition means you are at risk of developing type 2 diabetes, this technology could make a huge material difference. It is, as mentioned, pretty groundbreaking.
I think it’s really important to remember that your blood glucose is impacted by more than just food. And that if you are someone who obsesses over numbers, or calorie counts, or has a history of disordered eating, this wearable is probably not for you.
What the Lingo glucose monitor did show (and remind) me is that we all have highly personalised glucose responses to food, exercise, stress and sleep. And yes, understanding how our individual bodies respond to each of these factors can be a powerful way of improving our health.
But, when it comes to investing in your health, it’s important – as in all areas of life – to know your ‘why’. How valuable a piece of kit really is – whether that’s a wearable like a CGM or a Peloton bike – lies in how effectively it will help you to achieve your ultimate health and fitness goals.
Key (personal) takeaways
- When I drink alcohol, my glucose levels tend to drop quite low.
- The importance of properly fuelling before exercise is not to be underrated (on the days when I hit the gym straight after work without having a small snack first, my glucose levels plummeted).
- ‘Naked carbohydrates’ (eg pasta on its own without protein) massively spiked my glucose levels.
How to wear a pair a Lingo glucose monitor
If you’re interested in tracking your glucose levels, first ask yourself why and if you really need to. We also recommend working with a medical professional or dietician to help you properly understand all the different insights into how your body responds to food and exercise.
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With nearly a decade of journalistic experience – in print, online and social – at national newspapers and lifestyle magazines, it’s fair to say Alice has tried it all when it comes to health and fitness. From packing herself off to an extreme Aveduric retreat in Sri Lanka and sweat-testing every new fitness fad to running the London Marathon and completing a 70.3 IronMan, Alice now looks after WH’s food content. With a ‘food first’ ethos, she is here to help you decipher exactly which foods will support your health, and which macro-counting, pasta-replacing, intermittent-fasting, 13-day cleanse is just, well, a scam. A keen baker and host, her favourite dessert has to be pavlova (with lots of summer berries and whipped cream, of course).
