There are some hidden gems in the world of nutrition and fitness — findings that have interesting and useful implications outside of the general “eat this, not that” advice.
Resistant starch is one of them. The second meal effect is another.
Once you know these things exist, you can put them to immediate use. That’s what I love about them, they’re directly actionable.
Low carb diets are popular — especially among T2 diabetics — because of their regulatory nature when it comes to insulin and blood sugar. If you eat a high carb meal, you spike your blood sugar. Eat a low carb meal and you don’t.
Let’s say you eat a low carb (or low-glycemic) breakfast: the interesting part about doing so is that it doesn’t just have a positive effect on blood sugar at the time, it actually improves your PPGR (postprandial glycemic response) at the subsequent meal. This is termed “the second meal effect.”
Postprandial is a really fancy term for “after the meal.” PPGR is a gauge of hormonal and metabolic function (and thus health). If you have a functional metabolic and hormonal response and eat a high carb meal, you’ll see a certain spike in blood sugar (appearance) that is flushed from the body in a certain period of time (clearance): PPGR.
If you feed someone with a dysfunctional hormonal and metabolic response the same meal, you’ll see a bigger spike with a much greater struggle to flush the system back to normal. Their PPGR is worse. This person would benefit from a low carb lifestyle that avoids spiking blood sugar in the first place.
If you have a functional response, you still benefit from anything that will help you reduce spikes and flush blood sugar faster. Enter the second meal effect, where eating a low carbohydrate diet for a first meal makes you more carb-tolerant at the second meal.
Understanding this means that if you’re planning on ingesting a higher carbohydrate meal, you can time it optimally or strategically set it up.
Carbs come in handy when you’re actively working to increase performance; they restore glycogen stores; they improve sleep in some people; they help avoid physiological insulin resistance seen in long-term low carb diets and so on. But there are still hazards with regard to constant spikes and good blood sugar control reduces general risk for disease.
So if you can blunt the spike and aid clearance, that’s a good thing. Resistant starch does just that (among other things). And so does gaming the second meal effect.
In simple terms: if you’re planning on going higher carb for a meal — for whatever reason — low carb the meal prior to it. Don’t think of “2nd meal” as “lunch.” The name is a bit confusing. It should probably be called “the subsequent meal effect.”
If you eat a low carb dinner, your PPGR will be improved at breakfast the following morning (what most people would consider “first meal”). Make sense?
Understanding both the second meal effect and the positive effects of Resistant Starch, my recommendation would be to eat low carb along with RS supplementation prior to the meal where you increase carb intake.
Of course, don’t take my word for it — go buy a blood glucose monitor and verify for yourself. They’re insanely cheap for giving such important verification.
Kevin Geary is the founder of RebootedBody.com and a respected expert on cravings, eating psychology, and long-term habit change. He’s worked with thousands of men and women in over 35 countries around the world through his online academy and programs like Shut Down Your Sugar Cravings.