Blood Glucose & Your Body
While they tend to be recommended by fitness trainers, as a means of creating energy for exercise, carbohydrates are not required for energy.
They are however, the fastest way to get glucose into muscles.
Our body has two fuel types….glucose and ketones.
Your body is like a house with a heating system that is powered by mains gas….but with a bio-mass heating system that can burn wood-pellets instead when the gas runs-out.
I used to live in a house like this, and I used wood pellets most of the time to heat the boiler, and then flicked a switch that used gas instead when we ran-out of wood pellets.
Generally when one system is working the other isn’t.
When you take a bite of a carbohydrate-rich food (a juicy jam-filled donut, pizza, bread, pasta, potatoes, cereal, sugar, etc) those carbohydrates get digested and broken down into their simplest form in your body: glucose.
Your liver does the job of converting all those other sugars in these foods (anything that ends with “ose” like fructose, lactose, sucrose, etc) into glucose too so it can be used by your body.
The glucose is then sent to your bloodstream, which is where the term “blood glucose” comes from.
This quick rise in blood glucose signals your pancreas to release insulin, a hormone that shuttles the glucose to your cells for energy (your muscle cells first…when they are full fat cells and liver cells are used for storage).
It must do this because glucose cannot remain in the blood, it must be used or becomes very dangerous to us and if not cleared this can be fatal. (Ask any type 2 diabetic what the consequences of elevated blood glucose are!)
If you have periods of time when you don’t eat anything at all, or if you eat foods which are high in fats and proteins, then your body uses ketones for energy instead of glucose.
Ketones are produced by the liver.
Ketones have a few benefits over glucose as an energy source. When ketones are used, there is no requirement for insulin to be present.
This is great for fat-loss because insulin’s job is not only to shuttle excess blood glucose into empty (or new) fat cells, but it also signals existing fat cells to stay “locked”, to prevent even more excess energy circulating in the blood.
Insulin is elevated for a while after eating carbohydrates (up to a few hours for many people) which means that if we eat carbohydrates consistently throughout the day we will never have a period of time where our body is able to utilise stored fat. Not great if you are trying to lose weight.
What happens then if we only have small meals throughout the day, but each meal contain carbohydrates or sugar?
Well, there is a likelihood that even if you aren’t consuming many calories, you may not lose any body fat, if your insulin levels remain elevated.
Additionally, high blood glucose interferes with a hormone called leptin.
Leptin manages satiety (feeling full) and tells your brain that you no longer need. So elevated blood glucose can make you hungrier and cause you to eat more, even after you have already eaten!
So, ironically, eating carbohydrates for energy….may make you feel hungry, tired and low on energy.
Another benefit of using ketones for energy, is that if there are too many in our body for any reason they are just expelled through our breath. So we can make them on demand and excrete them if we don’t need them.
This means there isn’t the need to weigh and measure foods to ensure that you have the correct balance of energy-in v energy-out when your body is fuelled by ketones, but when fuelled by glucose you need to be careful not to have excess fuel, for fear of weight gain. Now, this brings us to the problems with high blood glucose.
Blood Glucose Issues
Let's say you ate more carbs than you need.
While your body may usually deal with occasional binges, if you constantly eat foods that elevate your blood glucose, your cells may eventually become insulin resistant, or your body may not be able to produce enough insulin to deal with the constant blood glucose rush. This can cause symptoms including:
Poor exercise recovery
Low energy and tiredness
Resistance to weight-loss
Feeling “hangry” or craving sugar/carbs
Blood glucose, not managed properly, can cause serious problems that affect even healthy people.
Why Healthy People Should Care About Blood Glucose
Blood glucose affects everything from your cells to your organs, and is one of the most important factors in your health. Even if you don’t think you have blood glucose issues, there’s still a possibility that it could be eroding your energy levels, leading to oxidative stress, causing skin issues, and making it hard for you to lose weight.
To create a day with steady, consistent energy levels, balancing blood glucose should be your number one strategy. You may have noticed that soon after the sugar “high” that you get from carbs, you may feel an energy crash! When healthy individuals consume more carbohydrates (or sugar) than their body can easily handle at once, blood glucose will quickly spike.
In response, your pancreas may over-correct, creating too much insulin into your blood, clearing all the available glucose.
You will then feel a period (before your body has had a chance to “flick the switch” to using ketones for energy, and before the liver can produce more glucagon) where your are running on empty. You know that feeling…..where you have a big bowl of pasta for lunch, followed by a dreaded 3pm slump over your desk at work. If you’re dealing with rollercoaster energy levels, like this example, you may want to consider ways to ensure your glucose levels are better balanced.
The up-and-down feelings caused by high blood glucose, can actually cause oxidative stress in your body.
Oxidative stress results from an imbalance between antioxidants (good) and free radicals (bad) in your body.
Free radicals are a well-known cause of cellular damage, disease, and perhaps even ageing.
On the other hand, antioxidants can counteract the negative effects of free radicals. When you have excess oxidative stress, like that caused by high blood glucose, you're generating more free radicals than antioxidants, tipping your body’s scales toward cellular damage. (You may now close your chemistry textbooks…) By causing oxidative stress, high blood glucose after a meal, can have a wide-ranging, negative effect on the body of even the healthiest people. The negative consequences of this may not be evident for a few years, so it’s a good idea to take preventative measures early with diet, exercise, and lifestyle strategies to maintain healthy glucose metabolism.
Poor glucose metabolism has been linked to acne and skin breakouts, especially in women. It is thought that, as your body produces more insulin to deal with blood glucose, androgen hormones are activated.
Androgens can stimulate skin sebum production in certain people, and excess sebum is a well-known cause of skin breakouts. Also, poor glucose metabolism has been shown to suppress sex hormone-binding globulin (SHBG), which is supposed to bind and capture excess sex hormones like androgens. This can cause further elevation of androgens. And if that’s not bad enough, elevated androgens can also contribute to making insulin resistance worse. Other issues, such as advancing the appearance of ageing skin, may also be linked to blood glucose. Researchers in the Netherlands studied over 500 non-diabetic patients, looking at their blood glucose levels.
Even after accounting for lifestyle factors, the researchers found that as blood glucose levels increased, the subjects’ perceived age (as indicated by skin health) also increased.
How to Balance Blood Glucose Naturally Research shows that exercise, sleep, stress, and fasting can all contribute to healthy glucose metabolism and blood glucose management.
There are also some dietary strategies that can help you improve blood glucose:
Foods high in protein not only keep you from overeating, but they also have much less of an effect on blood glucose.
Unlike carbs, protein takes a while to digest, preventing post-meal blood glucose peaks.
Many studies also show diets higher in protein (and lower in carbohydrates) result in better short- and long-term markers of blood glucose control. Increasing your protein intake can also increase muscle mass.
Muscle is the largest storage area in the body for circulating blood glucose, so having more muscle means more places to shuttle glucose, and therefore lower blood glucose levels.
Aim to eat protein at every meal and to consume 0.8-1.2 grammes of protein per kg of body weight per day. For an average man that is 64g - 96g of protein per day.
Be Aware Of Carbs
Most healthy people don’t need to completely eliminate carbohydrates, but if you have insulin issues or are sensitive to carbohydrates, then try to minimise them.
Many people find it harder to have a few carbs than to cut them out altogether (I am one of these people).
Once I have them, I start to feel more hungry, get cravings, feel tired and feel hot.
I actually feel great when I have no carbs at all, so I try to resist them altogether.
When I do indulge (family birthday cake or special nights out) it often takes me a fair bit of willpower to get back onto a zero carb die, but once I eliminate them for a day or two I feel great, don’t experience hunger, sleep better and have mental clarity and improved, constant energy levels. Learn what works for you, but if you do eat carbohydrates try to:
Stick to one serving at a time, preferably paired with protein
Choose unrefined complex carbohydrates, which have less of an effect on blood glucose (such as starchy vegetables, whole fruits, and properly prepared grains)
Save carb-rich meals for after exercise (when glycogen is depleted) and/or go for a post-meal walk, which decreases postprandial glucose spikes
But look… Carbs are delicious!
Writing this has made me fancy a piece of toast and jam!
Better get the dumbbells out!
For more on how to manage blood glucose, create better insulin sensitivity and generally improve your metabolic flexibility, check out me book Use Your Head, Heal Your Heart.