Hunger Hormones - Part 1
Insulin
In this part, we’re taking a deep dive into insulin. What it’s used for, why we need it, and how it affects our appetite and hunger.
What is insulin & why do we need it?
Insulin is a hormone that our body uses to manage the sugar in our bloodstream. Glucose, our main energy source, rises in our blood after we eat and reduces a few hours later. But glucose needs to be heavily managed in the body because it’s like a teeny tiny shard of glass…it can damage the cell if there’s too much.
Insulin is released in concert with glucose and helps the cell manage this little shard of glass. Insulin binds to a receptor site on the cell and opens up the glucose gate for one molecule to go in. Insulin stops glucose from flooding into the cell and causing damage.
We can see how helpful insulin is when we look at our brain and eyes. They don’t use insulin and they are the first organs damaged by high blood sugar. This is why diabetics are at risk of blindness and cognitive problems. Our whole body would be at risk if it wasn’t for our friend insulin.
But, like with all good things, too much is a problem.
If insulin is too high in our blood, then it triggers inflammation. High insulin comes from high blood sugar and high cortisol. So, let’s look at high blood sugar.
Blood Sugar Rollercoaster
So many of us are on the blood sugar rollercoaster that it seems normal. Of course, I get testy when I’m hungry. Of course, I get tired and crave sugar in the afternoon…doesn’t everyone?
Yup, everyone on the blood sugar rollercoaster does :)
I use the term “blood sugar rollercoaster” to describe the ups and downs we get when our blood sugar isn’t well managed.
The story of this rollercoaster usually starts with breakfast. If you eat a breakfast that’s not balanced for your lovely body, then your blood sugar might get a bit high. The biggest culprits are sweetened drinks (like sugar in your coffee) and refined food that is high in sugar but low in fibre, healthy fat, or protein. Think pancakes, 0% fat sweetened yogurt, or white toast with jam.
Once you’re on this particular rollercoaster you might feel a twinge of hunger mid-morning or you get VERY hungry if lunch is a bit late. These are signs that your blood sugar is a bit low and your body will ask for something sweet to bring it back up. We always overcompensate, so instead of a small boost, you get another spike.
The blood sugar rollercoaster is most evident by the late afternoon. The lunch spike is long gone and now you’re dipping really low. Lows always equal the high – a small high = a small low. A big high = a big low.
Now it’s 4pm or 5pm and you’re exhausted, hungry, grumpy, and your day isn’t over. Yes, your 4pm sweet craving is just a symptom of the blood sugar rollercoaster.
Symptoms of imbalanced blood sugar (rollercoaster symptoms) –
Tired and craving sugar around 4pm
Feeling hungry within 3 hours of eating
Your hunger feels – demanding, changes your personality, lowers your energy
You wake up feeling hungry or feel hungry in the middle of the night
You feel GREAT after a sweet treat…and then feel impatient, tired, and frustrated after about an hour
You have sore joints, inflamed skin, etc (Inflammation is triggered when our blood sugar is high)
Blood Sugar, Insulin, Insulin Resistance & Type II Diabetes
Your blood sugar and the hormone insulin dance together all day, every day. They’re partners and need each other to work properly.
When we eat food, our digestive system breaks it up into its chemical properties, carb, fat, protein, vitamins, minerals, etc. For this story, we’re going to focus on carbs.
The carbs in our diet break down into sugars – glucose, fructose, and galactose. ALL carbs break down to these sugars eventually (including non-starchy veggies) and that’s GOOD. We need these sugars!
Our body likes to run on a steady supply of glucose. Fructose and galactose are converted to glucose when needed by the liver. And extra sugars are stored in the muscles and fat cells for later use.
When we eat whole food carbs with lots of their natural fibre, it takes time for those foods to be broken down, so we get a slow and steady drip of glucose into our bloodstream.
When we eat refined carbs and especially when we drink a sweetened drink, the glucose heads into the bloodstream super quickly and we get a high boost of glucose. This puts us right on the blood sugar rollercoaster.
Now comes insulin -
Glucose in our bloodstream needs to move into our cells, and that’s where insulin comes in. Our pancreas gets a signal to secrete some insulin anytime we have glucose in our blood.
Remember, insulin is a hormone that acts as a gatekeeper for our cells. Our cells want glucose, but too much can damage the cell. If a cell is “hungry”, then insulin binds to a receptor site on the cell and that allows just enough glucose to enter the cell.
That process continues happily until the glucose gets low in the bloodstream…and then we feel hungry and it all starts over again!
When there’s too much sugar… (Insulin Resistance)
When there’s chronically too much sugar in the bloodstream, insulin becomes like an annoying neighbour to the cell.
Instead of waiting until the cell is hungry, insulin needs to get rid of all of this glucose so comes knocking at the cell. If the cell gets too much sugar for too long, then it might break its insulin receptor so the insulin can’t bother it anymore.
But…the cell will need sugar eventually and so it sends a signal that it’s hungry, but the insulin can’t bind anymore.
When this happens, we can feel hungry all the time even though our blood sugar is pretty high. And high blood sugar can trigger inflammation and damage arteries.
If this process continues and too many cells have damaged receptor sites, then our blood sugar can be high in blood tests. (this is fixable too…so don’t worry if you’re feeling these symptoms).
Symptoms of insulin resistance –
- sugar cravings after meals
- feeling tired after a meal
- trouble sleeping
Check out Part 3 or our Blood Sugar Masterclass to find balance :). But first, it’s time to learn about ghrelin and leptin, two hormones that also control our hunger.
Got any questions or comments? Comment below, jump to our private Facebook Group, or the Ask Lisa page :).