Summer’s around the corner and with it vacations, trips, fun stuff. Sticking to the best food choices, however, can be challenging when you're away from your routine.
Since I don’t subscribe to the notion that we should stick to a perfect diet all days of the year I want to believe that our body is forgiving, adaptable, and doesn’t expect us to be on our best behavior more than, let’s say, 80-90 percent of the time. To fully experience another culture, another country, an excellent restaurant I’d like to put aside food worries.
What are the consequences of letting go every once in a while?
The good – and the bad – news
A new study offers both reassurance and forewarning.
Researchers overfed a small group of young, healthy, non-obese men in two experimental settings, one resembling a holiday or a vacation – 5 days of indulgence – and another approximating chronic overeating – about a month of immoderation.
The study, published in the American Journal of Physiology – Endocrinology and Metabolism specifically chose to test the sort of over-consumption typical of a Western diet. The volunteers ate their normal diet, and on top of it had 1000 extra calories derived from high-calorie snacks such as chocolate, potato chips and meal replacement drinks. The researchers, led by Dale Morrison, measured many metabolic parameters, such as blood sugar and insulin, as well as C-peptide, an amino acid that is released in response to increased production of insulin.
And the results: 5 days of overfeeding had little effect on body weight and body fat, but 28 days changed body mass and fat mass: after 28 days participants gained on average 3.5 pounds of weight, of them, almost 3 pounds of fat. This is no wonder: 28 days of 1000 extra calories are 28,000 additional calories, much greater than the extra 5000 calories consumed after just 5 days.
What’s interesting is that after-meal blood glucose levels spiked only when participants overfed for 28 days. Insulin response was also increased only in the chronic overfeeding condition. These changes in insulin production and insulin clearance are suggestive of the emergence of insulin resistance – the body loosing its sensitivity to insulin.
This study is small, but may suggest that at least in healthy, young people, short-term overeating is buffered; the body regulates and shifts the excess energy so that glucose and insulin are kept quite stable, and even weight doesn’t change much.
On the other…