- Dr Jenna Daku
How is it ethical to starve adolescents for science?
** TRIGGER WARNING: Numbers and kcals are referenced throughout this blog**
Sadly, this is not a sensationalist title designed to grab your attention. Researchers in Australia are running a clinical trial called “Fast Track to Health” and they are literally starving adolescents in the name of research. Obviously, I've got a lot to say about this...
What is "Fast Track to Health"
They have recruited “obese” and “overweight” adolescents between the ages of 13 - 17 to engage in a 12-month clinical trial that is looking at the effectiveness of “Alternate Day Fasting” and “Reduced Calorie Plan” in weight loss and impact on cardiovascular risk factors. Participants randomly selected to engage in Alternate Day Fasting will be subject to alternate days of eating only 600-700 kcals per day and then maintaining a “healthy” food plan for the rest of the week. Those assigned to the “Reduced Calorie Plan” will be assessed by their assigned dietitians although the website does not give any information from the onset regarding what range of kcals this may include.
If we look at the recommended guidelines for calorie consumption in Australia, according to the country’s “Healthy Food Guide” it is recommended that adult women consume between 1800 – 2350 kcals per day, and adult men consume 2400-3000 kcals per day (dependent on activity levels). However, the guide explicitly states: “If you are younger, males should be consuming about 800kJ more, while females should maintain approximately the same kilojoule content as mentioned for the 31- to 50-year-old females.”
Now, I’m not claiming to be a maths genius here but if I am not mistaken, this means that the average female participant in this study will be consuming around 1/3 of their recommended caloric intake on fasting days, and the average male participant will only be consuming around 1/5 of the recommend caloric intake on fasting days. Since the trial lasts for 12 months, this means that these adolescents on the “Alternate Day Fasting” will be consuming between 1/3 and 1/5 of their recommended calorie intake for 6 months. The nutritional guidelines for the remaining days are not made clear on the website.
To put this in to context, this is 1/3 the calorie intake that the (adult male) participants of Ancel Keys’ Minnesota Starvation Experiment consumed (1800 kcals / day) (Kalm & Semba, 2005). The semi-starvation state that these men were subjected to has become a foundation for understanding the physiological and psychological effects of eating disorders. An extreme example of the potential psychological effects of prolonged starvation is highlighted in Todd Tucker’s Book “The Great Starvation Experiment”, which opens with a vignette of one of the research participants, known as Number 20, who chopped his own fingers off with an axe after several months of starvation.
Now, since I don’t have the exact numbers for the Reduced Calorie Plan, and I’m not about to guess given that this is such a haughtily contested topic, I’ll leave the numbers for now. But I am hoping that you can see how my concern leads me to question the ethics of this clinical trial.
What about ethics?
The topic of biomedical ethics is admittedly not a specialty of mine and it's also far too nuanced to get in to in any great detail in this blog post. However, I’d like to offer a couple of key points from “The International Ethical Guidelines for Health-Related Research Involving Humans”– a document created by the World Health Organization (WHO) and the Council for International Organizations of Medical Sciences (CIOMS).
Firstly, for a scientific study to gain ethical approval it needs to first show an extensive review of the literature that looks at the efficacy of past studies and interventions related to the topic at hand. The literature review provides a foundation for understanding previous research, and contextualising the ethical foundation for the study at hand. A strong scientific literature review will examine the evidence from various angles, and it won’t just go in to prove a specific point or angle. Basically, the researchers need to prove that they have taken every precaution to protect participants from undue harm, that the intervention being researched has the potential to improve health on a community and population level, that the information generated by the research has social value, and that it has scientific value as well (ie: it can be replicated with reliability). The literature review is the first point of exploring these issues. Again, this is a totally layman and brief overview of ethics and it does not reflect all the nuances.
Now, I won’t be writing my own literature review here, but we can assume that the researchers found some evidence to support the use of their chosen interventions. And I can’t deny that the research shows that dieting, fasting, and calorie reduction results in * short term * weight loss. For the purposes of this blog though, I’ll refrain from outlining that research. However, if the authors did a thorough literature review, they would have also outlined the research that shows that dieting and caloric restriction is ineffective in the long run and may predict future weight gain and metabolic disturbances (Fothergill et al., 2016). They also would have come across longitudinal studies on adolescents, one of which showed that “dieting and unhealthful weight-control behaviours predict outcomes related to obesity and eating disorders 5 years later” (Newmark-Sztainer et al, 2006). Or another 15-year longitudinal study that illustrated that dieting and weight control behaviours in adolescence and young adulthood predicts unhealthy weight control behaviours in adulthood (Haynos et al, 2018). The literature review would have also outlined the 7-year follow up study which showed that weight management behaviours such as fasting, vomiting, and skipping meals in obese adolescents predicted higher weight in young adults (Nagata et al, 2018). And since their research is focused on adolescents, they would have also discovered and outlined that family-based health centred interventions that focus on adults, rather than children, may yield better long term results compared to interventions that target children (Golan & Crow, 2012).
Given the outlined research, I am left questioning the choice of intervention used and whether it is necessary (and ethical) to submit adolescents to a year of prolonged ‘unhealthy weight management behaviours’ such as fasting and food restriction when the existing body of research has yet to prove consistent and reliable results. Especially given that WHO and CIOMS specifically state that “their distinctive physiologies and emotional development may also place children and adolescents at increased risk of being harmed in the conduct of research” and as such the ethics committee and researchers must insure that “the risks must be minimized and no more than minimal” (p.65). I’m no ethics expert, but it doesn’t exactly feel as though the risk to the adolescents participating in this study is ‘minimal’ given the context of the existing research on calorie restriction and weight management.
What about health?
Now, to be fair, from an ethical standpoint we need to consider whether there's a social basis for research like this, and we could argue that there certainly is given the current rhetoric around 'obesity'. Now, I’m not arguing the fact that there is evidence linking higher weight to negative health outcomes. However, correlations between weight and health outcomes does not mean that there is a causal relationship there. In fact, it’s extremely difficult to measure causal relationships in humans because we need to account for an enormous array of confounding variables (aka factors that can skew the data and interfere with the ability to establish a causal relationship). These include, but are not limited to, psychological, behavioural, social, environmental, cultural, biological, and genetic factors. Basically, it’s not as simple as saying ‘higher weight means higher risk of disease and death’.
I’m also not contesting that we need to find ways of improving our health, and that this is particularly true for vulnerable populations such as adolescents. However, we need to be sensitive to how we are defining health and whether we are taking in to consideration all of the relevant factors that contribute to human health and wellbeing. If we are coming from a holistic approach to health, and considering the delicate interplay between physical, psychological, social, emotional, and environmental factors it is hard not to question the current weight management approach.
When we look at the effects of our weight management efforts there is considerable evidence (around 50 + years worth) that what we are doing contributes to negative psychological and physical health outcomes and that it could be contributing to the very ‘problem’ we are attempting to ‘solve’ (aka ‘obesity’).
I can’t get in to all of this right now, because this post is getting long enough, but let’s take weight stigma in the context of the two above points. Weight stigma is a considerable health concern and form of prejudice, according to WHO (2017) . The incidence of weight discrimination is said to have increased by 66% between 1990 and 2000, to the point that some speculate it is comparable to the prevalence of racial discrimination in the US (Puhl & Hever, 2010). Research on the impact of weight stigma shows that it increases the overall state of chronic stress on the body and is linked with metabolic dysregulation and inflammation (Vadiveloo & Mattei, 2017) as well as lower self esteem, psychological stress, and body dissatisfaction (Puhl & Hever, 2010; Bacon & Aphramor, 2011). Furthermore, when we look at weight stigma in the context of behavioural changes, it has been linked with decreased engagement in weight-loss practices, binge eating, and an overall increase in caloric intake (Puhl & Hever, 2010).
So, although the current weight management paradigm claims to focus on health, when we break it down and look at other factors involved apart from short term weight loss and some short term health benefits, it becomes apparent that this paradigm is not only ineffective in the long term but may be causing harm – and this doesn’t even include the increased risk for developing a clinical eating disorder.
While we're talking about health, we need to talk about eating disorders:
Adolescents are considered to be the highest risk group for eating disorders. The average age of eating disorder onset, is somewhere between 10-20 years of age, and children under the age of 18 are twice as likely to develop a restrictive eating disorder than they are to develop type 2 diabetes (Pinhas et al, 2011). According to statistics obtained by Adolescent Growth via the National Institute of Mental Health, 95% of people with eating disorders are between the ages of 12 and 25 .
Furthermore, dieting and body dissatisfaction are among the top adolescent risk factors in the development of eating disorders (Rohde, Stice & Marti, 2015). To put this in to an experiential context, my current case load of clients who struggle with disordered eating and clinical eating disorders, 100% of them have an onset of disordered eating behaviour in adolescence. Whilst not everyone who diets will go on to develop a clinical eating disorder, every single person that has walked in to my consulting room has a history of dieting in childhood and adolescence. Every single one of them. There’s a reason why decades of research on eating disorder aetiology consistently outlines the need for adequate prevention methods aimed at adolescents…
How is this okay!?!
When we put this in the context of Australia’s “Fast Track to Health” trial, it makes me seriously question the ethical foundations for this research. Furthermore, as an eating disorder therapist, I am left feeling particularly concerned for the wellbeing of participants and the impact that 12 months of semi-starvation could have on their physical, emotional and social wellbeing. I am seriously concerned that this study is putting these adolescents at undue risk for developing a clinical eating disorder.
For me, the fact that this study gained ethical approval in light of my above arguments speaks volumes to the fat phobia that steeps our socio-cultural environment. At the end of the day, we are so desperate to eradicate ‘obesity’ that we will willingly and knowingly put adolescents in an environment that knowingly puts them at risk of developing a clinical eating disorder.
Seriously though, how is this okay?!?
Kalm, L. M & Semba, R.D (2005). “They starved so that others be better fed: Remembering Ancel Keys and The Minnesota Experiment”. History of Nutrition.
Tucker, T. “The Great Starvation Experiment” (2006). University of Minnesota Press.
Vadiveloo, M. & Mattei, J. (2017) “Perceived weight discrimination and 10-year risk of allostatic load among US adults”. Annals of Behavioral Medicine.
Puhl, R.M & Hever, C.A. (2010). “Obesity stigma: important considerations for public health”. American Journal of Public Health.
Newmark-Sztainer, D., Wall, M., Guo, J., Story, M., Haines, J., Eisenberg, M. (2006). “Obesity, disordered eating, and eating disorders in a longitudinal study of adolescents: How do dieters fare 5 years later?”. Journal of the American Dietetic Association.
Nagata, J. M., Garber, A. K., Tabler, J., Murray, S. B., Vittinghoff, E., Bibbens-Domingo, K. (2018) “Disordered eating behaviours and cardiometabolic risk among young adults with overweight or obesity”. International Journal of Eating Disorders.
Bacon, L. & Aphramor, L., (2011) “Weight science: Evaluating the evidence for a paradigm shift”, Nutrition Journal.
Fothergill, E., Guo, J., Howard, L., Kerns, J.C., Kruth, N.D., Grychta, R., Chen, K. Y., Skarulis, M.C., Walter, M., Walter, P.J., Hall, K.D. (2016) “Persistent metabolic adaptation 6 year after ‘The Biggest Loser””. Obesity.
Pinhas, L., Morris, A., Crosby, R.D., Katzman, D.K. (2011) “Incidence and age-specific presentation of restrictive eating disorders in children” JAMA.
Rohde, P., Stice, E., & Marti, C.N. (2015) ‘Developmental and predictive effects of eating disorder risk factors during adolescence: implications for prevention efforts”. International Journal of Eating Disorders.
Golan, M. & Crow, S. (2012) “Targeting parents exclusively in the treatment of childhood obesity: long term results”. Obesity Research.
Haynos, A.F., Wall, M.M., Chen, C., Wang, S.B., Loth, K., Neumark-Sztainer, D. (2018) “ Patterns of weight control behaviour persisting beyond young adulthood: Results from a 15-year longitudinal study”. International Journal of Eating Disorders.