|*Chart courtesy of C. Saladino, PhD, Professor of Chemistry & Biochemistry, Misericordia University|
Want some jellybeans with your books?
Shoes? Bolts & screws?
They sell candy everywhere now.
Let's think about this in the context of breakfast. Typically, when you wake up in the morning, your blood glucose and insulin levels are both fairly low. Even if you ate a sugary late-night snack right before bed, by the time you wake up several hours later, your body has done what it needs to go with the glucose and your numbers are back to normal. So now it's time for breakfast. There are two ways to go: you can consume a breakfast that will fill you up and keep you satisfied for hours without raising your blood glucose or insulin all that much. This would be a meal of primarily protein and fat: eggs and bacon; sausages and cheese; ham; leftover meat loaf; full-fat plain yogurt with some cottage cheese for extra protein; leftover chicken & veg. (Coffee with tons of butter and coconut oil...) You get the point.
OR...you could eat what we've been told for years is a more “healthy” breakfast: glass of orange juice; bowl of wheat & bran flakes with skim milk; fat-free blueberry muffin; granola bar; bagel with margarine or jam.
While that first breakfast will keep you going for several hours both physically and mentally, this second one is a recipe for blood sugar and mood regulation disaster. Right here at the start of the day, the poor unsuspecting soul who eats this “healthy, low-fat breakfast” has set him/herself up on the blood sugar rollercoaster, and they'll be holding on for dear life all day. Do you see how misguided it is to the start the day with a huge bolus of carbohydrate? (Maybe not for everyone, but if you're trying to lose body fat and/or prevent hypoglycemia and even out your mood swings, oatmeal and fiber bars are not the way to go.) Like Dr. Robert Lustig said, "Breakfast is not the time for your sugar fix."
Let's see what just happened in terms of setting the body up to be a sugar burner or a fat burner. Upon waking, just when the body is best primed to remain in fat-burner mode (courtesy of the low insulin levels), this low-fat dieter has just ingested a few wallops of carbohydrate--be they from sugary cereal that is obviously problematic or even from a “whole grain, complex carb" source, like multigrain bread. And with this, she has just given her body the unmistakable signal to NOT burn fat. To NOT use fat as fuel (either dietary fat from her food or her stored body fat—precisely what she is so desperate to get rid of.) By consuming that large amount of carbohydrate and raising insulin, she has essentially shut down the use of fat for fuel. So much for losing body fat with a low-fat diet. According to John Kiefer, “Your body starts each day as a fat-burning machine, and the key to simultaneous fat loss and muscle gain is to avoid screwing that up.”
This is what I mean when I say “the hormonal milieu.” Fuel partitioning is NOT only about how many "calories" we eat. It's about how the types of food we eat affect our hormones. (And for the love of all that's holy, do NOT let anyone tell you different!)
Nutritious breakfasts, or blood sugar bombs?
P.S. About cortisol: according to the chart above, cortisol breaks down fat but also breaks down muscle. And it turns the amino acids it gets from breaking down that muscle into glucose. (One of cortisol's primary purposes is to raise blood glucose levels in response to a stressor. From an evolutionary perspective, this stressor would have been a real, no-bull emergency, and you would have needed a lot of glucose flooding your system to give you quick energy to either stay and fight or RUN FOR YOUR LIFE. [Hence “fight or flight.”] A lion chasing you, trying to make you its dinner. A lion chasing your friend, and you want to make sure he is dinner, and not you. Okay, so cortisol gets released, blood glucose goes up, and then what? Insulin levels go up, too, right? And what did we learn about insulin today? It inhibits fat burning. So we’ve broken down muscle tissue to get at the amino acids to turn them into glucose, and we can’t burn all that much fat. Eek! It’s a metabolic double whammy. This is why there is actually “stress-induced diabetes.” Indeed, if you are a stressed-out, stressy stressball, you can make yourself diabetic even if you eat a pretty good diet. Piece of advice: calm the _____ down. Now.
P.P.S. Cortisol flooding your body with glucose isn't necessarily a bad thing. It's what is biologically hard-wired to happen, and at its heart, it is a protective mechanism designed to keep us alive in a very threatening situation. Problems with cortisol arise when we are constantly stressed out and do not fight or flee. If glucose floods our bloodstream because our bodies perceive the traffic jam, work deadline, or argument with a significant other, as an "emergency," and then we just proceed to sit there stewing in our car, at our desk, or on the couch, we might as well have eaten a donut and then vegged out on the sofa. (Well, no, it's not quite as dramatic a glucose spike as that, but you can see what I mean.)