When it comes to food and fat, we all think we know what’s right and healthy but we’re only getting part of the picture. You see, nutritional science is still a young art and there are many things that still haven’t been discovered. There are others that have only become apparent in recent times.
Leptin, one of our key hormones is one of those “new” discoveries. Just 9 short years ago in 1994 it came into the spotlight of scientists researching obesity and looking for biochemical means. Since then a relationship has been found with various hormones that are key in driving our fat storage capacity.
1. Leptin – involved in appetite and energy regulation
Leptin is a hormone released by fat cells and is the ruler of energy regulation. Leptin is the one telling your brain that you’ve got enough energy stores in your fat, that you don’t need to keep eating, and that you feel okay. But what if your brain can’t hear what leptin is telling it? Then your appetite signal is never switched off and your body thinks you need to keep consuming more energy and store more fat for energy too. Your brain also signals your body to feel lazy in order to conserve that energy. To increase energy storage, the brain signals more release of insulin to push more energy into fat cells.
But most people overweight are actually leptin resistant and therein lies the problem. The more fat cells you have the more leptin you have, remember leptin is a hormone that is released by your fat cells, so more fat=more leptin=leptin resistance. What’s happening with increased weight gain or obesity is that your brain can’t see the leptin calling out, so your brain thinks you’re constantly starving.
Leptin is also meant to slow down our feeling of reward associated with food. But when that doesn’t happen we feel we need to eat the food to gain the reward and never feel satisfied. Does any of this sound familiar to you?
2. Insulin – the energy storage hormone
Insulin is the hormone that gets triggered when we predominantly eat carbohydrates, aka sugars. Many people think that eating fat is what makes us fat but it’s actually sugar and carbohydrates and that’s where insulin comes into play. The blood sugar levels in our body are kept in a very tight range, so when we eat sugar or carbohydrates, insulin is the hormone that helps to bring those blood sugar levels back within the normal range. But the extra sugar circulating in your blood has to go somewhere, because excessive high or low blood sugar can be life threatening.
So what happens to the excess sugar? Some of it gets stored as glycogen in the muscles and liver, the gycogen is there so your body can break it down when it needs more energy. But most of us aren’t using our conserved energy and are eating too much energy, so insulin pushes the excess into fat stores and our body has UNLIMITED capacity for creating fat cells. The most predominant type of fat cells in our body are triglycerides. Triglycerides are made up of a glycerol (sugar) back bone and then 3 fatty acids attach to that sugar to make a fat cell (triglyceride).
There’s a lot more involved in insulin action, but we’ll leave that to another time. When the brain can’t see the leptin signal, it also causes more insulin to be released and therefore more fat storage. Having high insulin inhibits the leptin signal to the brain. The more insulin, the more fat, hence the reason why we have an obesity epidemic. It’s not the fat, it’s the high consumption of sugar and carbohydrates.
3. Cortisol – the most predominant stress hormone
Cortisol is our stress hormone and we can probably all agree that stress is a major factor in modern day life. Adrenal fatigue is becoming a common condition associated with cortisol. Too much cortisol will also increase blood sugar levels and promote the release of more insulin. Cortisol promotes increased food intake and the consumption of comfort foods. I’m sure you can relate to times you’ve been under stress and reached for the chocolate or cake?
Cortisol also promotes the storage of the worst type of fat for our health, visceral fat, otherwise known as belly fat, something we all love…not
4. Ghrelin – the hunger signalling peptide
Ghrelin is produced in the stomach and gives us our hunger signal. It’s the one that tells us it’s time for lunch and makes our tummy rumble. When we eat, ghrelin levels rise and after we’re finished they are meant to lower. But excess sugar and carbohydrate consumption doesn’t switch off the ghrelin signal so after a meal ghrelin stays high and we feel like we need more food. So we eat more and keep perpetuating the vicious cycle that these hormones play together.
When it comes to losing weight we are constantly trying to work against the natural processes of our body, but as Dr Robert Lustig says “The biochemistry always comes first”. Our biochemistry drives the body but it also drives our behaviours. Hormones are very powerful and as you can see from all of these sneaky hormones making you fat, when one thing is out of balance, a cascade of events gets ignited and puts everything out of balance.
Can we fix the hormones making us fat? Yes we can and the answer lies largely in what we eat.
Join me for a FREE weight loss webinar (online meetup) next week. I’ll be covering weight loss principles and how to get off the dieting merry go round.
I hope to see you there
P.S. Invite your friends along too by sharing this post. We all need to quit dieting and start living!