Insulin is, by current accounts, the greatest scourge to a lean physique, long-term health, smart children, world peace, sexual competence, NAFTA, singularity, the economy, the rain forests, climate change, your mother, your father, and your brothers and sisters. In short, you should panic and throw yourself from the nearest window. Since the nearest window is on the first floor, I merely got a bit wet (it’s been raining). Hopefully you smacked your head and came to your senses: we have insulin for a reason. Today, I’d like to shine the light on a study that shows we might be able to determine our “best” diet from our fasting insulin levels.In the study “Insulin sensitivity determines the effectiveness of dietary macronutrient composition on weight loss in obese women,” subjects were given a diet based on their fasting insulin levels. Those who were insulin-sensitivity (fasting insulin < 10 microU/mL) were given a high carbohydrate/low fat diet (60%cho/20%fat, HF/LF). Those who were insulin-resistant (fasting insulin > 15 microU/mL) were given a “low” carbohydrate/high fat diet (40%cho/40%fat, LC/HF). I put low in parenthesis because I don’t think 40% of calories from carbs is particularly low, though certainly lower than what one would see in the Standard American Diet…which is shit to begin with. Conclusion?
RESULTS: Insulin-sensitive women on the HC/LF diet lost 13.5 +/- 1.2% (p < 0.001) of their initial BW, whereas those on the LC/HF diet lost 6.8 +/- 1.2% (p < 0.001; p < 0.002 between the groups). In contrast, among the insulin-resistant women, those on the LC/HF diet lost 13.4 +/- 1.3% (p < 0.001) of their initial BW as compared with 8.5 +/- 1.4% (p < 0.001) lost by those on the HC/LF diet (p < 0.04 between two groups). These differences could not be explained by changes in resting metabolic rate, activity, or intake. Overall, changes in Si were associated with the degree of weight loss (r = -0.57, p < 0.05).
Those who could tolerate higher carbs got better results eating higher carbs. Those who couldn’t tolerate higher carbs got better results eating lower carbs. Excuse me while I pass out from total and utter shock…ok, now that I’m awake what the hell do we know? Well, this study was very unique in that all of the meals were prepared in the lab for the subjects and there were weekly weigh-ins and dietary compliance discussions. Quite controlled and I think it shows just how placing a blanket statement about any macronutrient is short-sighted, or in this case, misinformed.
So what’s the take home?
- Pay attention to your fasting insulin level during your next blood test. If you’re not happy with your physique, make some adjustments.
- This doesn’t mean that, if you’re insulin sensitive, you should eat high carb junk. EAT REAL FOOD, but now you can make more of those sweet potato fries you’ve been jonesin’ for. Health is still paramount.
- If you’re making a change, pay attention to how your body feels; you might be insulin sensitive but still subjectively feel better on lower carbs. Trial and error here will go a long way toward better health.
- There is no universally applicable carbohydrate level for all humans, full stop.