Getting empowered and onboard with tech tools. Let’s talk about blood glucose levels, our master hormone insulin, and CGMs.
I’ve been tracking my blood sugar for years now. I am not diabetic nor pre-diabetic. Metabolic health is at the forefront of learning to THRIVE, which is what I coach my clients on as a clinical nutritionist. We live in an era where low-profile wearable devices give us biofeedback so that we can optimize our choices and therefore our health. Examples of the sorts of ‘tech tools’ I love and personally use every day are my Oura Ring for sleep tracking, my Apple watch for exercise and my continuous glucose monitor (CGM), and a glucometer for tracking my blood glucose levels. I use the Freestyle Libre CGM to track, which uses a filament inserted into my interstitial fluid (the fluid that surrounds our cells) on my upper arm that looks like a little white button. What I love about using a CGM for myself and my clients is that its evidence-based data. Whatever dietary camp you follow whether it’s keto, paleo, carnivore, vegan, vegetarian, whatever, we can all obtain objective data on every choice we make. This is powerful. Being able to create sustainable behavior change with closed-loop feedback for myself, my family, and my clients is a game-changer.
When I am in the scientific literature it is extremely apparent to me how much of our health lies within our control. Discovering the tremendous downstream consequences of metabolic dysfunction, I recall reading my mum’s labs one day back home in Sydney, Australia. Not only were specific biomarkers well out of the optimal ranges (she already had hypertension and hypothyroidism) she was also pre-diabetic. Her endocrinologist and I sat down and with regards to her pre-diabetic state and he told me that he can’t do much until my mum has diabetes. Modern medicine is a Godsend in certain situations, however, it is reactive and not proactive in terms of prevention. Thankfully, he was open to discuss how diet and lifestyle can reverse metabolic dysfunction, and together we came up with a plan.
Metabolic dysfunction enables dis-ease in our body and our brain. Obesity, hypertension, PCOS, pre-diabetes, diabetes type 2, Alzheimer’s (often called type 3 diabetes due to insulin resistance in the brain), cognitive decline, hyperinsulinemia, stroke, CVD, and infertility. Increased anxiety, depression, mood disorders, and fatigue are also symptoms of metabolic dysfunction. A whopping 88% of the US population alone are metabolically unhealthy, and 90% of people in the US don’t even know they are pre-diabetic. The problem is that there is no feedback loop when it comes to our diet and lifestyle choices. Most of us know that high sugar processed foods won’t move us in the direction of our goals, and that whole food is a better choice. That’s a great start, but it’s not enough. Now tech companies are stepping in and the personalized data is showing how our choices today can either prevent or contribute to disease down the road. Metabolic health is LIFE. It is a critical underpinning mechanism for both our physical and mental health.
Tracking data using a CGM and lab biomarkers helps me as a clinician to individualize treatment and empower my clients. Getting to see what’s happening under the hood and discovering with real-time data how what they just ate, when they exercised, whether they got enough sleep, and how stressed they feel provides us with a tangible feedback loop. No practitioner can offer you this invaluable type of real-time biofeedback on how your choices are directly affecting your metabolic health. Tech is turning this around and putting the power into our hands. I think of it like this: Would I prefer someone to tell me what to eat (they would be guessing), or would I prefer my body to speak to me directly with real-time biofeedback via my CGM? I choose the latter. Do I stay plugged into my CGM all the time? As a non-diabetic I have the luxury of not needing to be plugged in all the time, but I use it often for insights and direction. I love having a healthy relationship with all of the tools I use and believe it’s also useful to sometimes take a break and not track.
The CGM for myself and my clients only confirms that my thrive lifestyle and my rooted in science #5tothrive formula is extremely efficacious at supporting blood sugar balance throughout the day.
“Metabolic fitness is something we work towards. We have to build it brick by brick. We build new habits and we build momentum and we get consistent. The CGM offers real-time data that gives us a closed feedback loop so we know which direction we are headed in.” ~ Priscilla
I often get a lot of questions in my DM’s on instagram @thrivewithpriscilla when I talk about using my CGM, so I thought I would answer some of the repeated ones here:
What exactly is metabolism?
In short, metabolism is the set of hormonal processes in our body that takes our food and the environment (eg: sunlight) and turns it into energy. Every cell in our body requires energy to function. When these processes are compromised there are dire consequences that adversely impact our quality of life and longevity. We have 5 levers that can modulate metabolism: Nutrition, exercise, sleep, stress and sunlight. The exciting news is that these are within our control.
What about the glycemic index? Can’t I just follow that and have balanced blood sugar?
Glucose is our primary energy molecule. We can produce energy from carbs (glucose), protein, and fat. Our body prefers to stay in a very specific glucose range, and when we are out of range dysfunction occurs. The glycemic index is a way of measuring how a specific food compares to pure sugar, and how that affects blood sugar control. The problem is that it is normalized to 100. This means that it’s working on average. Unfortunately, it removes individuality and nuances that a glucometer and CGM biofeedback can give us. For example, brown rice is better than white rice when compared to pure sugar, however, you and I will show variables in mmol/L or mg/dL when comparing pure sugar, white rice, and brown rice. Your blood sugar may not spike with brown rice and my reading may show a significant spike. A study showed this at The Weissman Institute in Israel in 2015, where scientists used CGMs to continuously monitor 800 non-diabetic participants’ blood sugar levels over 47,000 meals focusing on how certain foods trigger responses in post-prandial (post-meal) blood sugar. Researchers found that when participants ate the same meals they individually had a completely different post-prandial blood glucose response. This study undermines the efficacy and sufficiency of the generalized glycemic index due to significant variability. It also illustrates the importance of individualized nutrition and why someone can lose weight on a particular diet and another person on the same diet cannot.
Aren’t calories in vs calories out more important?
The principles of energy balance and thermodynamics are not flawed. If we take in more energy (calories) than we expend we will gain weight. If we take in less energy than we expend we will lose weight. That said, there’s an elephant in the room that counting calories leave out. It doesn’t take into consideration the hormonal and biochemical cascade that occurs after we consume food. It also negates the importance of meal composition. It’s not only the calories that matter when it comes to energy balance, it’s also the hormonal effects. The hormonal theory of weight balance says, ‘The context of our decisions will drive hormones which will affect how our bodies manage the energy.’ For example, if you have a high blood sugar spike your body must release a high amount of insulin to correspond to that spike. Insulin’s job is to remove the sugar out of the bloodstream and store it. It will shuttle the glucose to your liver, and if that’s full to your muscle cells next to be stored as glycogen. If your muscle cells are full of insulin (eg: you’re not moving) then it shuttles the glucose to be stored in your adipose tissue, aka your fat cells. Yes, calories matter, but equally so too do the hormonal effects when it comes to energy balance.
How does exercise impact blood sugar? Is there a preferred type? What does metabolic flexibility, metabolically fit, and fat-adapted actually mean?
HIIT training or weight lifting often releases cortisol and sometimes adrenaline. These hormones elicit a stress response in the body. They tell our body to hold onto the energy (flight/ fight response) for our muscles (and brains) because we may need to run like the wind from a bear! Both cortisol and adrenaline inhibit insulin, therefore insulin cannot do its job of getting the glucose into our cells. In turn, we may see a blood sugar spike on our CGM. This is caused by our liver dumping stored glycogen into our bloodstream, or producing it from macronutrients, protein, fat, or carbs known as ‘gluconeogenesis’ to fuel our workout. The physiological effects of a spike due to intense exercise on blood sugar are very different than a spike from consuming sugar. The research on high-intensity interval training (HIIT) shows a strong correlation between bouts of intense exercise and insulin sensitivity. Research shows that after an intense training session our body responds more efficiently to the insulin levels in our body, meaning we require less insulin per unit of glucose to remove it from the bloodstream. Practically speaking, if you can train in the morning you’re potentially setting yourself up for better blood sugar levels throughout the day.
Training at a high intensity in a threshold between fat oxidation and glucose oxidation is advantageous, however many people cannot or do not want to train this way. The best way to understand this is that our body can use different energy systems. For example, when we engage in HIIT we primarily burn pure sugar for energy (anaerobic exercise). Conversely, when we engage in a lower intensity exercise (aerobic exercise) our body switches to burn primarily fat for energy. When you train fasted at the high end of your aerobic threshold and consume a higher healthy fat diet your body increases its ability for fat oxidation by utilizing your fat stores instead of your sugar stores. This makes you ‘fat adapted.’ You become a fat-burning machine well after the workout is over. We can switch between food energy (glucose) and our own stored energy (fat). When we train fasted we double down on the fat-burning benefits. Switching over from a sugar burner to a fat burner is known as being ‘metabolically fit, or ‘metabolically flexible’. This has been shown to greatly improve mitochondrial efficiency, which is the energy-producing ATP powerhouses within our cells.
Our muscles are our largest glucose disposal tanks. They also determine our carbohydrate threshold. Our muscles pull glucose into their cells when we contract them without the need for insulin. This is why studies on resistance training show it to be highly efficacious in improved blood sugar control and insulin sensitivity. All exercise in the literature has been shown to have a positive affect on blood sugar, and hence insulin.
Can walking positively impact blood sugar levels and insulin?
The short answer is YES! If you’re not into HIIT or strength training, the good news is that all exercise in the scientific literature has been shown to improve insulin levels. A brisk walk after a meal has been shown to support blood sugar balance and help to reduce a potential spike. Exercise across all studies shows a positive impact on blood glucose regulation and therefore insulin sensitivity.
How important is sleep when it comes to blood sugar levels and insulin?
Sleep studies have shown just six hours of sleep can increase insulin levels by 40% when compared with eight hours of sleep. As little as one night of poor sleep has been shown to put participants within a pre-diabetic range. This is why aiming for around 7.5-8 hours of sleep is optimal, especially for those trying to improve their insulin sensitivity, metabolic health, or to lose fat. Poor sleep significantly increases insulin levels and dysregulates our hunger hormones and satiety signaling in particular ghrelin and leptin. In turn, we crave more fast-release sugary carbohydrates the next day, which sends us on a blood sugar rollercoaster that is then compounded by increased insulin levels. This is a recipe for disaster! Alcohol when consumed at night adversely affects sleep (sorry folks!), which is also something to watch.
I’ve heard fruit is good then it’s bad. Juicing is good then it’s bad. I’m so confused!
If we look at everything nature it’s in its whole form. All plant foods are wrapped up in fiber. Mother nature knows fiber will slow the release of sugar from the fruit into our bloodstream. Emerging science also tells us that our gut microbiome affects our blood sugar levels from the meal we’ve just consumed. What are our good gut buddies preferred fuel? You guessed it, fiber! When we strip out the fiber we fasten the release of glucose into the bloodstream and deprive our good gut bacteria of its food. Juicing carrot and celery for example is going to impact blood sugar a lot differently than if we consumed them in their whole form. Similarly, if we add protein and fat to the fiber in these veggies we will have a further improved blood glucose response, as protein and fat blunt glucose. If you want to have a juice I recommend doing so with a meal, try and get some leafy greens in and minimal to no fruit. Remember too that fat-soluble vitamins such as vitamins A, D, E, and K are not bioavailable to us for uptake in the body if we aren’t having fat with them, so have a spoonful of nut butter or some avocado with your juice!
If I monitor my blood glucose what’s the goal?
In short, staying within the optimal ranges is going to move you in the direction of optimizing your metabolic health. Riding blood sugar high peaks and low valleys along with staying high has long-term negative health implications. High spikes and low crashes can lead to downstream cognitive decline with feelings of low mood, the shakes, fatigued, tired, and hangry up to 2 hours after a meal. Blood sugar imbalance and insulin resistance cause inflammation in the body such as inflammatory cytokines, C-reactive protein, interleukin-6 – all of which are closely connected to our immune system.
The goal is to see rolling hills and a smoother ride within the optimal ranges (mmol/L or mg/dL) on a CGM for myself and my clients. Sharp high peaks and valleys are what we want to steer away from along with blood sugar staying elevated for hours after a meal and not coming back down to base level. Over time this creates insulin resistance whereby our cells stop responding to insulin’s signal to deposit more glucose from the carbs we consume. This is also how weight gain often occurs.
How can intermittent fasting help with blood glucose & insulin?
Intermittent fasting (IF) is not for everyone including children, adolescents, pregnant women, nursing women, and those with specific health conditions. It is always best practice to speak with your physician first before engaging in any type of fast. Please see my other blog post on intermittent fasting HERE which discusses a recent study as it pertains to weight loss, IF for women, and circadian intermittent fasting, which I coach some of my clients on. Within the scientific literature, time-restricted eating primarily refers to human trials, while time-restricted feeding mostly refers to animal studies; however, both terms are used interchangeably.
Circadian rhythm signalling has an impact on blood glucose levels and insulin. In one study researchers found that the post-prandial (after meal) glycemic response to the same meal consumed in the morning and again at night had a different response. In other words, glucose was lowest in the morning and highest at night, which suggests we have a lower glucose tolerance at night than we do in the morning. Another study found that when participants followed an early time-restricted eating schedule their hunger levels were diminished, and they felt satiated faster due to satiety signaling hormones (leptin) being higher and appetite-stimulating hormones (ghrelin) being lower when compared to the control group. I have been practicing circadian rhythm intermittent fasting for 8 years now and anecdotally can attest it has greatly improved my satiety signaling and metabolic flexibility. Most of the studies in the literature are on men, or mixed women and men when it comes to time-restricted eating. In terms of resistance training, one study showed an 8-hour time-restricted eating window in healthy males resulted in a decrease in blood glucose, blood insulin, and fat mass while maintaining muscle mass. More trials need to be conducted.
My personal CGM data
Below, I have included some snapshots of the data from my CGM. This is the sort of data I interpret with my clients along with their labs which then helps us to make an informed individualized actionable sustainable plan moving forward. I prefer to take a test don’t guess approach and personalise their plan. Getting specific as to what is working and what isn’t and how their daily choices are directly affecting therm is powerful. Before you look at my data I have shared below my morning routine. After I drop the kids off at school I train in the morning I strength train and resist my muscles for approx. 45-55 minutes fasted. I usually break my fast with my Thrive Smoothie around 10:30am after a 16 hour circadian intermittent fast. It’s important to note context when observing data because I have already set myself to optimise my blood sugar. My data is in mmol/L as that is the metric we use here in this part of the world. You will need to convert to mg/dL if that is your preferred metric. Postprandial optimal levels are within a tight rage. I aim for between: 3.9 – 6.1 mmol/L or 70 – 110 mg/dL.
None of the aforementioned information above is in any way sponsored.