Following my first post about Carbs vs Fats, I’m looking into insulin resistance and Type 2 diabetes. I always thought of diabetes as an irreversible illness where you’d have to take injections every day for the rest of your life. But I’ve learnt a bit more and the great news is, that’s not true.
First, some basics:
- What is insulin? Insulin is a hormone that helps glucose get into your muscle cells. After you eat a meal, the carbohydrates are broken down into simple sugars that enter your bloodstream, and in response, your pancreas secretes insulin. The insulin reaches the cells in your muscles, prompting them to accept the glucose molecules which will power the cells.
- What is insulin resistance? It’s a condition where your cells fail to respond to insulin. If you are insulin-resistant, your cells fail to respond to the insulin and the glucose molecules are unable to enter the cells. The glucose then builds up in your bloodstream.
- What is diabetes? Type 2 diabetes is a disease where your blood glucose levels are consistently too high, due to your cells not responding to insulin. Type 1 diabetes, which is less common, is a disease where your pancreas does not produce enough insulin.
- What can happen? High blood glucose levels, over time, can damage your blood vessels and your nerves, possibly resulting in atherosclerosis, heart disease and stroke, blindness, and diabetic foot ulcers (which can lead to amputation).1Centers for Disease Control and Prevention. About diabetes. CDC.gov. Published June 1, 2017. Available at: https://www.cdc.gov/diabetes/basics/diabetes.html. Accessed March 22, 2019.
Type 2 diabetes is a serious and life-threatening disease that afflicts millions of people in countries that have picked up the ‘western diet’ centered around animal products and junk food. It’s a lifestyle disease: it typically comes about as a result of dietary habits (not genetic luck-of-the-draw).
To date, all the conventional wisdom that I’ve been exposed to (from what you’re told in school and what you read online, to third-hand info from acquaintances with diabetes or insulin resistance) has essentially said that carbs are the culprits and in terms of dietary intervention, the only thing to do is to reduce your blood sugar levels by limiting your carb intake. Avoid bread, limit fruit and fruit juice, cut out all sweets. No mention of any other foods or macronutrients: carbs are the red flag.
But now that I’ve done a bunch of reading myself and learnt about the metabolic processes involved in blood sugar and insulin levels, I have a better understanding of how diabetes interventions work.
Let’s look at the traditional treatment: insulin injections. They’re absolutely necessary for Type 1 diabetes, but for Type 2 diabetes, it’s not so clear.
- Consider that the number one risk factor for diabetes is obesity2Alberti KG, Zimmet P, Shaw J. International Diabetes Federation: a consensus on type 2 diabetes prevention. Diabet Med. 2007;24(5):451–63. (why? I’ll explain later).
- Consider, also, that insulin not only ‘unlocks’ your muscle cells’ glucose receptors, allowing the simple sugars into the cell to fuel your workouts – it also promotes the storage of fat in our fat cells.
- If we have insulin resistance or diabetes, our cells don’t respond adequately to the insulin our pancreas produces.
- So, we take an insulin injection to flood our bloodstream with insulin and try to ‘force’ the cells to accept the blood glucose after our meal.
- But then what happens after the now-elevated insulin levels? Remember that insulin promotes fat storage…
- We gain weight, increase (or perpetuate) our insulin resistance, and the cycle continues.3Williams KJ, Wu X. Imbalanced insulin action in chronic over nutrition: clinical harm, molecular mechanisms, and a way forward. Atherosclerosis. 2016;247:225–82.
We’re stuck: we do our best to reduce the symptoms of the disease (elevated blood glucose) by avoiding high-carb foods, and keep ourselves alive with daily insulin injections – all the while not questioning why our cells are insulin-resistant in the first place.
But why DO we develop insulin resistance in the first place? Typically, we’re either born with elevated insulin levels4Le Stunff C, Fallin D, Schork NJ, Bougnères P. The insulin gene VNTR is associated with fasting insulin levels and development of juvenile obesity. Nat Genet. 2000;26(4):444–6., or we develop insulin resistance from too much fat in our bloodstream. Intramyocellular lipid (IMCL), or the fat inside our cells. If we consume a high-fat diet, or if we are extremely overweight to the point where the lipids in our fat cells ‘spill over’ into our bloodstream, the fatty acids are absorbed into our muscle cells. There, they break down into free radicals and other elements that then prevent insulin from doing its job (i.e. unlocking the cells and allowing glucose to enter) – this is insulin resistance.5Brown A, Guess N, Dornhorst A, Taheri S, Frost G. Insulin-associated weight gain in obese type 2 diabetes mellitus patients: what can be done? Diabetes Obes Metab. 2017;19(12):1655–68.
Here’s the thing: animal products are causally associated with insulin resistance, while whole plant-based foods dramatically reduce blood insulin levels.
Saturated fat from animal products gets into our bloodstream and then into our muscle cells, breaking down into toxic components that prevent insulin from doing its job.6Cnop M, Hannaert JC, Grupping AY, Pipeleers DG. Low density lipoprotein can cause death of islet beta-cells by its cellular uptake and oxidative modification. Endocrinology. 2002;143(9):3449-53. On the other hand, plant-fats have the opposite effect: the fats in nuts, seeds, avocado and other whole plant foods are safely stored away, without affecting our cells’ ability to use insulin.7Nolan CJ, Larter CZ. Lipotoxicity: why do saturated fatty acids cause and monounsaturates protect against it? J Gastroenterol Hepatol. 2009;24(5):703–6.
As for protein? A particular kind of amino acid – building blocks of protein – in meat, dairy and eggs (branched-chain amino acids, or BCAA) has been found to spike blood insulin levels in a way that plant proteins (e.g. from legumes) do not. Add egg white to your otherwise plant-based meal, and an insulin spike results. The same goes for fish, dairy and other meats. Switch out the animal protein for plant protein (try tofu, nuts or beans) and you won’t get that spike at all.8Nie C, He T, Zhang W, Zhang G, Ma X. Branched chain amino acids: beyond nutrition metabolism. Int J Mol Sci. 2018;19(4):954.
There are several studies and many, many accounts of reversal of diabetes with plant-based diets.9Anderson JW, Ward K. High-carbohydrate, high-fiber diets for insulin-treated men with diabetes mellitus. Am J Clin Nutr. 1979;32(11):2312–21. I know there are claims made by keto-enthusiasts that you can ‘reverse’ diabetes through a low-carb diet: but this is not actual reversal of the disease, it only prevents elevated blood glucose levels by restricting carbohydrate intake. Real reversal of the disease means that you’re no longer intolerant to carbohydrates: you can eat a jam sandwich without needing an insulin injection to handle the glucose.
Why are we telling people to continue with inconvenient, expensive and painful insulin injections, that keep us in a spiral of sickness and line the pockets of pharmaceutical moguls, rather than halting the disease in its tracks with good food? You tell me.