Monday, May 09, 2016

Why I'll Never Prescribe a Very-Low-Energy Diet

A VLED is a "very low energy diet", and it's defined as one providing fewer than 800 calories per day. These programs are generally administered by physicians, are expensive, often take the form of meal replacement shakes, and usually last for around 12 weeks.

Multiple meta-analyses on VLEDs have been conducted, and generally their findings haven't been particularly exciting. Either they've concluded they aren't worth prescribing, or they've concluded that there isn't sufficient information for a conclusion.

Well add another meta-analysis to the pile. This one, published in March in Obesity Reviews, had what I found to be a very odd conclusion, and I'll get there in a bit. Ultimately the researchers findings were that when compared with a standard, and non-extreme, behavioural weight loss program, 3-5 years later, VLED patients will have lost 2.86lbs more.

Bare in mind too, VLEDs are challenging for patients. Can you imagine 12 weeks of just shakes? I've heard stories of people having to bring their meal replacement shakes to weddings, or to chug them in place of Christmas dinner. VLEDs have risks too. Gallstones from overly rapid losses, disproportionate loss of muscle mass, and electrolyte abnormalities.

So when I read that 5 years later, with VLED diets being shown to affect an additional half pound lost per year, and with their associated risks, and their not insignificant costs (both actual dollars and the cost to a patient's ability to live a normal life), I figured that certainly, the authors' conclusion will have to be that there's not much point in recommending them to patients.

Nope.

Despite VLEDs being found to barely lead to additional losses, despite their risks and their costs, the study's authors concluded,
"Adding a VLED to a behavioural weight loss programme produces greater weight loss in the medium and longer term than a behavioural programme alone. Such programmes appear well-tolerated. Current advice against their use for routine weight loss in medical clinics should be reconsidered."
Huh? Am I missing something?

While there are true success stories with every approach (including VLEDs), weight lost through suffering tends to come back.