Hope everyone had a great Thanksgiving. I was in Pennsylvania and computer-less so I was unable to even think about training for the five days. I learned a few good things during my break though:
- I’m God-awful at laser-tag. I was never very good at Halo or COD when my friends played, so I should have seen this coming. All the little kids kicked my ass.
- I’m not as bad at go-kart racing. In fact, I was pretty damn good at that.
- Yes, it’s confirmed. Any side-dish with sweet potatoes in it is officially the best side-dish at any meal.
Allow me to introduce the topic of this post by quoting the Part I of Insulin-based Nutrition:
“So where are we going from here? Here’s the thing: almost all of these diets include improved insulin sensitivity as a benefit. But what if we’re looking at this from the wrong angle? Instead of using insulin as the end goal, what if we could draw from these current strategies and just manipulate insulin in the first place?”
This is the second post in the insulin-based nutrition saga and it has been a long time coming (about two weeks). It will cover the different hormones that interact to make us hungry, full, stressed, tired, and so forth. It shouldn’t be too long, so here we go.
Insulin may be the most important hormone in the body, as it is central in regulating cellular glucose uptake, increasing protein synthesis, and promoting satiety.
Insulin is released from the pancreas in response to elevations in blood glucose. It forces the liver to go through a process called glycogenesis, which takes simple glucose and turns it into glycogen to be stored. Insulin also tells muscle and fat tissue cells to take up glucose in order to remove it from the blood. In this way, insulin controls blood sugar levels.
Similarly, insulin promotes what we think of as the “sugar crash” after a meal heavy in carbohydrates. This is known as reactive hypoglycemia, or the rapid rise and subsequent decline of blood glucose levels.
High blood sugar levels are bad. High blood sugar levels indicate an insensitivity to insulin, which can lead to diabetes.
Insulin controls protein synthesis (rebuilding muscle) via amino acid uptake, while also regulating storage of glucose as triglycerides in fat tissue (makes you fatter). Furthermore, insulin helps stop the breakdown of proteins, as well as gluconeogenesis (the production of glucose from non-sugars, such as amino acids and fatty acids.) For all of these reasons, insulin may be one of the most anabolic hormones in the human body.
Without it, it would be nearly impossible to build muscle.
Glucagon is the antagonist hormone to insulin. When blood glucose levels drop, such as after a long day of fasting, glucagon levels are high.
Glucagon promotes both gluconeogenesis (the breakdown of amino and fatty acids) and glycogenolysis (the breakdown of glycogen into glucose).
Leptin and Ghrelin
Leptin and ghrelin are antagonist hormones, in a similar way to insulin and glucagon. Ghrelin is highest right before a meal and lowest immediately following the meal. In short, higher circulating ghrelin levels make you hungry and increase food intake.
Interestingly enough, ghrelin may help defend against symptoms of anxiety and depression, as well as stimulate growth hormone. It also may be partially elevated in response to stress, which explains why I eat my feelings.
Ghrelin levels are not related to obesity, except in certain cases, though a difference in the circadian rhythm of obese individuals may contribute to lack of sleep, which in turn leads to elevated ghrelin levels. Ghrelin levels are negatively correlated with body weight, so levels rise when weight is lost and levels fall as weight is gained. In this way, ghrelin seeks to regulate body weight.
On the other hand, leptin levels are directly proportional to body fat levels. In this way, leptin is more like a messenger that sends signals to the brain, letting it know to decrease food intake and increase energy output. Therefore, leptin promotes satiety and fullness.
Cortisol is a hormone released in response to stress and serves to spare glucose by promoting gluconeogenesis (breakdown of amino and fatty acids for glucose production). Cortisol prioritizes your body’s processes during stressful times by diverting energy away from processes that it deems less important (e.g. the immune system). For this reason, prolonged elevated cortisol levels can, at the very least, hurt your recovery from gym sessions or make you prone to getting sick.
Cortisol acts against insulin by inhibiting the use of glucose in the body, instead promoting the breakdown of proteins and fatty acids. For this reason, prolonged elevated cortisol levels can promote the breakdown of muscle tissue. It also inhibits the uptake of amino acids by cells, decreasing protein synthesis.
Cortisol is very catabolic, will not help recovery from training, and can even waste away your muscle tissue.
Human growth hormone (HGH) is a steroid, yes, but it is also a hormone that promotes growth, cell reproduction, and cell regeneration in humans. It’s release from the anterior pituitary gland is stimulated by things like deep sleep, fasting,peptide (ghrelin) and sex hormones (testosterone), and vigorous exercise. Also, vigorous sex.
It increase muscle mass through sacromere hypertrophy, increases protein synthesis, stimulates the immune system, increases lipolysis (formation of free fatty acids), strengthens bones, and promotes gluconeogenesis in the liver.
It also promotes growth of all internal organs (one of the reasons long-term steroid use is bad).
Fun fact, nearly 50% of growth hormone is produced in the third and fourth stages of NREM sleep.
In short, human growth hormone is the BOMB.com.
Conclusion (aka the only part you care about)
Let’s try and summarize this post. First off, here’s a quick list of the hormones and their positive effects in terms of fat loss, muscle building, energy levels, and overall health.
- Insulin (controls blood sugar levels, increases protein synthesis, stops protein breakdown)
- Glucagon (breaks down fatty acids)
- Leptin (regulate hunger and metabolism and promotes satiety)
- Cortisol (sucks, may or may not break down fatty acids)
- Growth hormone (makes you a beast)
So overall, what can we take away from this post (can you tell I love using bullets to summarize things?):
- Insulin spikes make us tired and should be controlled for overall health purposes
- We should avoid elevated cortisol levels at all costs
- Growth hormone rules and makes us awesome
- Ghrelin stimulates growth hormone, as well as hunger, and has a host of other benefits
- Leptin is also our friend
- Fasting, insulin spikes, and stress management are all tools and factors that should be manipulated in a nutrition plan
- Growth hormone and insulin do not exist together, so we must be carefully manipulate both
So there’s that. This was not an exhaustive explanation of the body’s physiological processes and how the different hormones interact, but more of a summary of the effects of these hormones and how you can benefit from manipulating them.
The third and final part of the insulin-based nutrition saga is on the way and will help pull the first and second posts together into executable ideas that you can include in your nutritional strategy.