Very low‐energy and low‐energy formula diets: Effects on weight loss, obesity co‐morbidities and type 2 diabetes remission – an update on the evidence for their use in clinical practice

Abstract

The role of formula very low‐energy diets (VLEDs, <800 kcal/day) and low‐energy diets (LEDs, 800–1200 kcal/day) within clinical practice has regained attention over the last few years. Formula diets can achieve clinically significant weight reduction in the short‐term (3–5 months) and new evidence demonstrates that long‐term weight loss maintenance (up to 4 years) is achievable. Weight reductions of between 10% and 15% bodyweight have been reported, which is associated with clinically meaningful health outcomes in a number of obesity‐related co‐morbidities including type 2 diabetes (T2D), obstructive sleep apnoea and osteoarthritis. Recent evidence indicates that using a formula LED with a weight loss maintenance programme can help people with overweight or obesity and T2D achieve remission. Despite this, few healthcare professionals in the UK routinely use LEDs. Concerns about adherence, risk of precipitating eating disorders, safety, cost and long‐term efficacy may, in part, contribute to their under use. To help inform healthcare professionals on the use of formula diets within clinical practice, this review examines the current evidence for the use of VLEDs and LEDs for weight loss and weight loss maintenance, and in the treatment of obesity‐related co‐morbidities, including T2D, osteoarthritis, psoriasis, obstructive sleep apnoea and secondary coronary prevention, with a particular focus on T2D remission.

Pragmatic management of low‐energy diets in people with type 2 diabetes in primary care: a decision aid for clinicians

“…In counselling a person considering a low‐energy diet, we note that it is most effective as part of a multicomponent approach including behaviour change. We also acknowledge that low‐energy diet research is not as yet generalizable, and there are gaps in knowledge regarding application and impact in ethnic populations, and wider health implications . Suggested management may not be suitable for all, so clinicians are advised to adopt an individualized approach and seek expert advice where uncertainties arise.…”

“…Our observations from practice and previous research have highlighted the need for monitoring throughout the diet, which can be achieved through a combination of reported self‐monitoring and clinical review. Timely management can ameliorate the well‐documented transient side effects of low‐energy diets, such as constipation, fatigue and headache . Responsive adaptation of the medication plan can help avoid and manage hypoglycaemic events for those prescribed insulin and sulfonylureas, whereas efficient supported reintroduction of treatments can optimize care in the post‐diet period.…”

Very Low-Energy Diets—Opportunity for Greater Weight Loss, but Risk of Bone Loss

“…10 Moreover, increasing evidence suggests that greater weight loss can help achieve type 2 diabetes remission. 4 Finding strategies successful at achieving sustained weight loss in individuals with obesity should be an absolute priority in public health research. The TEMPO Diet…”

“…2 The finding that more than 80% of women in the severe group achieved 10% or greater weight loss is encouraging, as this can provide clinically meaningful health benefits. 4 Eventually, policy makers need to consider whether the risks associated with reported greater hip BMD loss and a potentially associated higher fracture risk exceed the benefits of the greater weight loss 4 achieved with VLEDs compared with moderate caloric restriction. Given the considerable burden of obesity, this seems unlikely at the population level, but may differ between individuals.…”

“…2 Indeed, the rapid weight loss, satiety, and feasibility of VLED use may contribute to improved adherence. 4 Successful weight loss and maintenance with VLEDs is generally reported when VLEDs are accompanied by additional weight loss maintenance support. 4 Going forward, we need a better understanding of the totality of (positive and negative) health outcomes with different weight loss strategies.…”