Keeping
lost weight off is notoriously difficult. A recent two-year
experimental study helps to shed light on just why it's so hard: cutting
calories and losing weight causes long-term increases in the hormone ghrelin
that increases hunger. To truly keep the pounds away, people have to
deal with feelings of increased hunger for the rest of their lives.
This
study provided a structured highly supportive weight loss program for 35
Norwegians who were morbidly obese. At the outset, all participants underwent a
three-week inpatient program in which all meals and snacks were
provided. The inpatient program also provided intensive instruction
in how to achieve and maintain healthy behavioral change with nutrition
education and psychological counseling. Participants also
participated in daily exercise routines. Over the course of the next two years,
four more three-week inpatient sessions were completed. Throughout
the study, all participants were placed on a moderately calorie restricted
diet, consuming about 500 calories per day less than otherwise needed to
maintain one’s weight. The macronutrient breakdown of the diet was 50%
carbohydrates, 30% fat and 20% protein. Between inpatient stays,
participants were advised to continue exercise and maintain a healthy diet
similar to that provided at the center. On average, the participants
lost about 11 lbs. (~4% of bodyweight) within the first three weeks of the
program, and an average of 24 lbs. (~9% of bodyweight) at the end of the
two-year study.
At
both the one- and two-year marks all the patients reported feeling increasing
hunger following their weight loss. Why did hunger levels increase?
Results indicated that as weight went down, levels of the hormone that drives
hunger, ghrelin went up. Ghrelin levels went up with initial weight
loss and these levels stayed up even as patients maintained weight.
On
top of the increase in hunger, people's bodies become more efficient in using
energy after weight loss. For example, on average, a person who has
weighed 176 lbs. their whole adult life can maintain their weight consuming
about 400 more calories daily than a person who has come down to 176 lbs. after
previously weighing more.
What
to do: The take home message here is that weight loss maintenance
requires deliberate lifelong dietary and lifestyle changes. To minimize
ghrelin increases during weight loss, it helps to lose weight gradually over
time without drastic decreases in calories consumed. To cope with
increased hunger it helps to increase intake of low calorie fluids and
non-starchy vegetables. It also helps to adopt a healthy balanced diet
that does not profoundly differ from one’s usual intake. For example,
diets that radically switch up your intake such as very low carbohydrate diets
are unlikely to be maintained and are especially associated with weight regain.
It is also recommended that in order to keep weight off, individuals need to
engage in 60 minutes or more of physical activity most days. Odds of
maintaining activity are best when exercise is social and when one does
activities one enjoys. Recording intake and portions also is positively
associated with weight loss maintenance. The likelihood of morbidly obese
individuals keeping weight off over the long term is much better with bariatric
surgery, partially because the surgery significantly reduces hunger. Even
though it is hard to keep lost weight off, remember maintaining even modest
weight loss of 5-10% of bodyweight can meaningfully improve your health.
And, regular activity and better food choices have many health benefits even if
they do not result in weight loss.
Source
Coutinho SR, Rehfeld JF, Holst JJ et al. Impact of weight loss
achieved through a multidisciplinary intervention on appetite in patients with
severe obesity. American Journal of Physiology Endocrinology and
Metabolism, 2018; DOI: 10.1152/ajpendo.00322.2017
Information adapted from
articles available at:
www.sciencedaily.com/releases/2018/02/180201123318.htm