Low Glycemic Breakfast Helps You Burn More Fat

I’m guessing that everyone who reads this blog is doing something to lose weight, either dieting, exercising or better yet, doing a combo of both.  But the research on what foods to eat when and in relation to exercise is still unclear to most, for example, what’s the best food to eat before you workout?

Some research suggests that exercise and diet interact together to influence health, such as exercising after short-term fasting (like before breakfast) may increase the amount of fat burned, or eating a meal that elicits a low blood glucose response (like high fiber meals) prior to exercise to boost the use of body fat instead of glucose.  But now it seems we have some more confirmation that low glycemic is indeed the way to eat before you hit the gym.

A group of researchers at the University of Nottingham conducted a controlled human intervention trial in more sedentary exercisers.  As expected, they found that blood glucose concentrations were higher after the high glycemic index or HGI meals than the low glycemic index or LGI meals, and had returned to baseline levels by the time exercise was finished, after which they were not influenced by breakfast eaten.  Plasma free fatty acids (FFA) a marker for adipose oxidation or fat burning, fell after consumption of both types of breakfasts, but began to rise at 2 hours post-breakfast in the LGI and not HGI treatment—meaning, the body was using up fat more when the subject ate an LGI breakfast.

Circulating concentrations of FFA were not different between treatments following lunch.  Overall, fat oxidation was higher in the LGI treatment than in the HGI treatment during the post-breakfast and exercise periods. Following lunch, fullness scores were higher in the LGI trial than in the HGI trial.  Bottom line: the authors concluded that consuming a low glycemic index breakfast increases fat burning for energy during exercise and improved satiety during recovery in sedentary females.  So the take home message is that those of us trying to shed fat should choose a LGI meal prior to exercise and it may be best if we workout after breakfast!