Question: My 25-year-old daughter is doing a cleanse — which involves eating nothing and drinking just a vegan protein shake for seven days. Apparently, after that she will introduce foods gradually and monitor her reactions to see what foods she should avoid. She is going to a personal trainer and I have no idea what his qualifications are — but I am certain that he is not qualified to be prescribing something like this. She won’t listen to me but she might listen to you. Is this safe and does it make any sense to you?
Dr Grant replies: I think you are right to be alarmed. This type of ‘cleanse’ is certainly not recommended by any medical professionals, registered dietitians or any personal trainer that I have ever met. It is possibly even dangerous as it could lead to nutritional deficiencies, extreme fatigue, dehydration, muscle wasting and worst case scenario, even an eating disorder.
Having an unhealthy preoccupation with food, body weight and shape can potentially lead to one of the more prevalent types of eating disorder known as Avoidant/Restrictive Food Intake Disorder (ARFID). An adult with ARFID does not eat enough calories to maintain basic bodily functions and exhibits three primary features:
⬤ Avoidance due to the sensory characteristics of food (sensory food aversions).
⬤ A lack of interest in eating or food (food avoidance).
⬤ Worries about the consequences of eating (phobia affecting food intake).
What is your daughter’s motivation in undertaking such an extremely restrictive dietary measure? I can only assume it is to lose weight. I wonder exactly how overweight she is. As part of her initial assessment, I assume the trainer estimated her muscle mass and percentage body fat and set some achievable targets over a defined timeline. What is her baseline fitness? Has she been actively involved in club sport, gym classes, personal training programmes in the past? Has your daughter ever suffered any mental health disorder such as depression or anxiety? Does she have a history of substance misuse?
As you can see, there is much more to controlled weight loss under expert guidance. Like all experts, you need to check their credentials before you fall into a marketing trap and believe in their often false promises. Food is one of the major pleasures in life. No one should be deprived of that luxury and certainly not opt into living on protein shakes for one week in order to undergo a ‘cleanse’. Whether the protein shake is vegan or whey protein (more commonly used) is arbitrary. You can get results (build muscle and burn fat) with both. Whey protein is derived from milk that is processed to make it low in calories, lactose, carbohydrate and fat.
That brings me to another question. Is your daughter attempting to become a vegan and what are her motivations? Once again, if done for the right reasons, under the right conditions, with appropriate nutritional supplements, in conjunction with a healthy lifestyle, becoming a vegan may provide additional health benefits.
Lastly, your comment about her plan to then slowly reintroduce specific food types and ‘monitor her reactions to see what food she should avoid’ made me wonder does she have concerns about food intolerance or possibly underlying Irritable Bowel Syndrome (IBS). These two conditions really need the expertise of a registered dietician who will also be able to decide if your GP or a gastroenterologist may need to be consulted.
Dr Jennifer Grant is a GP with Beacon HealthCheck