An hour with Professor David Cummings
During the 18th International Congress for Endocrinology the CEMMS Social Media Team had the privilege of taking an hour of Professor David Cummings’ time to discuss different topics under the umbrella of obesity and weight loss. To put it mildly, Dr Cummings is incredibly astute in his field and has received numerous awards throughout his tenure in the United States, including funding from the President himself. (perhaps insert bio here) Throughout the conversation we were fortunate enough to record several of his breakthroughs which we now aim to share with our audience.
Genetics vs Environment
Stigmas are undeniably one of the greatest hindrances to the treatment of obesity and, as such, we broached the topic with Professor Cummings regarding the best methods to combat these stigmas. In addressing this incredibly complex issue Professor Cummings enlightened us with the findings of several scientific studies which sought to examine the impact that one’s environment plays in determining body weight when compared to genetics. Of these findings, the most telling results were those of the twin and adoption studies. To explain the method of twin studies in simple terms, biological traits are compared between identical and fraternal twins. It can be reasonably assumed that both sets of twins share a common environment to a similar degree because they are usually raised in the same household. It must be remembered that identical twins have identical genetics and fraternal twins do not. In studies such as these, the concordance of body weight, meaning that the body weights of the two compared individuals during adulthood are within 5% of one another , was found to be over 80% in identical twins and less than 30% in fraternal twins. This is obviously a huge difference even they have a similar degree of environmental sharing. The other type of studies explained to us was adoption studies. In adoption studies children who are taken away from their biological parents at birth are observed and the question is asked “as adults, to what extent do they share body weight traits with their adoptive parents when compared to their genetic parents?” In simple terms, comparing the effect of genetics and environment. In these studies there was found to be a strong relationship between the body weight of adult children and their biological parents whom they have never met and no relationship whatsoever between the weight of the child and the weight of the adopted parents despite the fact that the adoptive parents possessed full control of the child’s developmental environment . In conclusion, it was found that in conditions of plenty about 80% of body weight is determined by genetic predisposition and only 20% is determined by environmental influence.
Body weight “ballparks”
To better explain the above point Professor Cummings explained that genetics place an individual in a body weight “ballpark” - for example, 300 pound Samoan man or 100 pound Japanese woman- and that variation in this “ball park” through diet, exercise or medication will only result in about a 5% change. So, in applying this change a 300 pound person would drop down to 285 pounds. While this change might not be a visible or aetehic one Professor Cummings elucidated that even a small amount of weight loss confers disproportionate health benefits. In short, diet and exercise will not usually lead to huge amounts of weight loss but will still result in a plethora of other health benefits and such should be highly encouraged. Individuals suffering from obesity may, through valiant efforts, be able to lose a significant portion of weight but will find it incredibly difficult to transcend the boundaries of their genetic “ballpark”.
Keeping the weight off/ Yo-Yo dieting
In our discussion another important topic was addressed - keeping the weight off. It is a common occurrence that individuals who lose large amounts of weight through diet and exercise eventually regain this weight in the years to follow. Professor Cummings brought to our attention that studies were carried out to determine whether or not weight fluctuations during one’s teenage years are more likely to lead to obesity during adulthood. These studies involved continually forcing rats to lose and regain 20% of their body weight through a 50% reduction in calorie intake. It was found that, when allowed to regain the weight, the rats would put on weight until they arrived at almost the same weight they were at before the diet began. This trend continued, with the diet-free weight being lower with each repeated cycle. They never regained weight to the point they would have been at had they never dieted. The conclusion to this studies (in rats, at least) is that it is better to continually try and fail than to never have tried in the first place.
Debate, debate, debate
In our conversation with Professor Cummings we asked his opinion on the importance of international congresses such as ICE. In his reply he emphasised the importance of disseminating the findings of researchers to other medical practitioners in order to derive practical benefits from said research. Part of this involves rigorous academic debate and discussion and without this environment of discussion the benefits of surgery in the treatment of diabetes would likely never have been discovered.
Perhaps one of the most pertinent topics of conversation with Professor Cummings was regarding the safety of bariatric surgery. There are myriad misconceptions regarding the safety of bariatric surgery procedures, which Professor Cummings attributes to the spread of misinformation. He attributed this to the spread of “horror stories” - tales regarding operations which aren’t necessarily true but stick in people's minds and find their way around in conversation. To mitigate this, Professor Cummings simply suggested a proper communication of facts: the 30-day mortality rate for bariatric surgery is incredibly low - 0.2 percent - behind only knee replacement surgery and elective hysterectomy and is statistically safer than a gallbladder removal or an appendix removal. In short, the myths surrounding the dangers of bariatric surgery are just that - myths.