These are notes on a presentation done by Dr Jack Kruse as part of the Paleo Summit done by Underground Wellness. Dr Kruse is a neurosurgeon, was obese himself and regained his health and lost weight by adopting the paleo diet. Along the way he learned about the hormone leptin and it's significance in our health.
What is Leptin?
Leptin is a hormone that is made in fat cells. It ties in with almost every other hormone in the body. It's a structural analog with a cytokine called IL 6. People who are obese or are very thin are often leptin resistant. He says "leptin resistance underpins inflammation". He also says "to me, obesity is not a disease, obesity is a symptom of a huge underpinning biochemical process in our bodies". He goes on to explain that a leaky gut and consumption of a diet that is mismatched to the biology of an animal is the root cause of this bioche4mical process, of obesity.
More on Obesity....
He says that the 3 problems of obesity are inflammation, which begins in the gut, which as he says is the interface between our diet and our immune system. The second step is when that inflammation moves out into the body into our organs, which are not all affecte4d the same way. Lastly, once the inflammation reaches the brain, he says that is really the root cause of all the "neolithic" diseases...what he calls the diseases of modern living.
Leptin and Circadian Rhythms...
Leptin evolved in relation to the major cycles that we have on earth, the light/dark cycle of day and night as well as geothermal cycles. He says that watching things with bright lights, such as video games, at night disrupts our circadian systems- it disrupts our sleep, which can alter our metabolism, and can actually cause inflammation at the brain level that can lead to leptin resistant and weight gain.
How Does Leptin Resistance begin?
Generally speaking though, he explains that leptin resistance begins when we eat a diet that is not suited to our biology and thus results in inflammation in the gut. This inflammation is seen by the immune system, which lies just below the lining of the gut, and which initiates a huge number of biochemical reactions in response, including the release of an array of cytokines. Eventually those cytokines get into the brain in places where there is no blood-brain-barrier (I also have to wonder about the presence in our environment and medicine of substances that cause the blood-brain-barrier to become permeable). He says the area most relevant to leptin resistance is one called the Area Postremo, which correlates directly to the Vagus Nerve which forms the Gut-Brain Axis.
Is a Calorie Really a Calorie?
Mainsteam medicine and dietetics tells us that a :calorie is a calorie", but it's not that simple. The response of our hormones to calories determines how those calories are partitioned. In our muscles we have proteins called uncoupling proteins that allow us to burn energy as free heat. Uncoupling means that we can eat a lot of food and then release some of those calories as heat.
Let's talk About Technology...
While animals are dependent on their environment, humans are able to alter and create our environment. Our ability to d to this- to alter our physical reality to meet our desires more often, has resulted in a evolutionary mismatch. Our cultures have evolved faster than out genes have so that we make choices, such as what to eat and when, that were not biologically possible during the time that our genes were evolving. Not only are we in a struggle between our brain and our genes every day, our brains actually have the power to alter our genes as what we eat has that power. Further, the agricultural revolution was the beginning of this- of humans eating in a way that is not a match for our biology, the beginning of chronic inflammation.
Let's Talk About Inflammation...
We need to limit inflammation so that we can reach our health potential. We can do this by bring our living conditions such as what we eat and our sleep cycles back in line with our biology. Disordered hormones are a sign that there is a mismatch somewhere in the body. The incongruity of the way we live our lives with our biology is a constant stress on our leptin receptors, which ultimately results in inflammation in the body.
What About High Cholesterol and Heart Disease?
The way that Dr Kruse got healthy was to do the opposite of all the conventional wisdom about health that he learned in medical school. 80% of our brain is made of cholesterol, and every hormone in our body is made of cholesterol. How could it make sense that such vital parts of our body could be made of something so bad for us? Cholesterol is turned into hormones by thyroid hormone and vitamin A, so having "elevated" cholesterol can function as a reservoir to allow our body to respond quickly to hormone changes when needed. If we have inflammation in our bodies, this inflammation can cause cholesterol to oxidize, which is problematic.
The Role of the Gut...
Dr Kruse says if we don't feel well, we can't think well. That a healthy gut is critical to a healthy mind. Good brain function means that our neurotransmitters are balanced and working well. We need to have certain nutrients coming in to our systems to keep this happening. It's not entirely true that we are what we eat- it's more accurate to say that we are what we assimilate. if our guts are inflamed, and we aren't digesting and absorbing our food well, then we won't be able to keep our brains at optimal functioning level.
For more on Dr. Jack Kruse's leptin plan and how to do it, go here.
