Insulin resistance: Genetic research shows an unexpected twist
Confronting my biases.
Hi there,
I love having a member-supported site, which allows me to avoid financial biases, like promoting certain supplements or diets. But that doesn't mean that I don't have personal biases that creep into the articles, as much as I try to keep everything balanced.
My most recent article has challenged me on some personal nutritional biases...
This article on insulin resistance has been in the draft stage for months. I kept going back to the research, trying to figure out what I was missing. My expectation was that sugar in the diet caused insulin resistance - and if not sugar, then probably industrial seed oils or toxins in the environment.
First, a little background:
Insulin resistance affects ~14-23% of the population, depending on how you define it. Essentially, insulin resistance means that cells don't respond as they should to the insulin signal telling them to take in more glucose from the bloodstream.
There are thousands and thousands of peer-reviewed research articles on insulin resistance, and almost all of the studies gloss over the mechanism of what causes the insulin signal not to be properly received by the cells.
Nothing seemed to really explain the "why", and many genetic studies of insulin resistance fail to distinguish it from diabetes. I just kept going around in circles, and so the article languished in my draft folder for months...
Then I started looking at Mendelian randomization studies on IR and found that they didn't point the finger at sugar or PUFA or environmental toxins, but instead showed a causal role for branched-chain amino acids (BCAAs). Mendelian randomization studies are used to determine causality using known genetic variants. Contrary to my expectations, when I started digging into it, there were several decades of research and lots of studies that show that branched-chain amino acids (BCAAs) play a causal role in insulin resistance.
Dietary sources of high BCAAs include chicken breast, Greek yogurt, whey protein, beef, and eggs (all foods that I assumed should be eaten in abundance to prevent insulin resistance).
And yes, high fructose can also cause insulin resistance. But the studies in humans show that it takes a lot of fructose, more than most people consume.
My takeaway from reading so many studies on insulin resistance is that it's not as simple as I thought, and that I need to be careful not to let my personal dietary preferences get in the way.
Before you email me back and tell me that I'm wrong and that keto/carnivore/LCHPMF is best for IR, please read the whole article and the references. Then you can email me :-)
I've left the article open for non-members to read just for this week, so please share it soon with your friends and family.
Wishing you well this holiday season!
~ Debbie
Insulin Resistance: Learning from Genetic Research
Key takeaways:
~ Insulin is a hormone that regulates glucose levels in cells and throughout the body. It binds to receptors on cells, causing glucose transporters to move to the cell surface and take glucose into the cell.
~ The term insulin resistance indicates that the signal from insulin is not properly received by cells and the receptors do not move to the cell surface to take up more glucose.
~ Insulin resistance can lead to diabetes. Even before diabetes develops, insulin resistance can have negative health consequences.
~ Genetic variants can make you more or less likely to develop insulin resistance, depending on your diet.
~ Importantly, genetics can show which cellular pathways are involved, including the role of BCAAs in insulin resistance.
Read the full article here
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