DPR-session-1-energy restriction

Very Low Energy (kilojoule/Calorie) Diets

The invention of Very Low Energy Diets (VLEDs) stemmed from an interest in creating a weight loss therapy that could produce outcomes comparable to starvation but without the increased risk of morbidity and mortality.
The precursor of VLEDs began in 1915 when high protein food-based diets of 1,700 – 2,500 kJ (400 to 600 Calorie) were used for rapid weight loss to treat people with obesity.
Liquid drinks comprised almost entirely of high-quality protein (milk casein or egg albumin) or a combination of protein and carbohydrate (egg albumin and sucrose or glucose) were later developed to create a semi-starvation state with success.

However, in the late 1970s, liquid milk formula-based diets began to be produced from low-quality protein (hydrolysed collagen or gelatine) that was nutrient incomplete and led to 60 deaths in the USA.
The deaths were later attributed to cardiac complications resulting from a starvation response from prolonged and extremely rapid weight loss (~30% body weight in 4 months) in otherwise healthy people with obesity.
Higher-quality protein and more nutritionally complete VLEDs are now used and clinical trials from the early 1980s ‘til now, show that VLEDs are a safe and highly effective weight loss intervention for the management of obesity.

Food-based VLED

An example food-based 3,350 kJ (800 Calories) per day meal plan:
Breakfast	1/3 Cup oats 2/3 Cup milk
Morning tea	Tea/coffee
Lunch	½ small can salmon or tuna 1 cup salad vegetables
Afternoon tea	Tea/coffee
Dinner	90g lean beef/chicken strips 1/3 Cup noodles 1 ½ Cup stir fry vegetables 1 teaspoon oil
Dessert/supper	2/3 Cup plain yoghurt 1 small piece fruit

Low Energy (kilojoule/calorie) Diets

Both overweight and obesity are associated with the incidence of multiple health problems, including, but not limited to:

Diabetes: progression or remission?

recently, type 2 diabetes was considered to be a progressive condition.
Following the path:
normal glucose tolerance → pre-diabetes → type 2 diabetes.
Disease management has primarily focused on delaying progression rather than achieving remission.

Publication of evidence about the reversibility of type 2 diabetes in the UK in 2011 was followed by over 1000 enquiries from people with diabetes.
The overwhelming sentiment expressed was profound relief at the possibility that the condition was not inevitably permanent.
Prevention/remission will reduce treatment costs and the additional burden of disease due to macro and microvascular complications.
Diabetes reversal should be a goal in the management of type 2 diabetes.

Reduced Energy Diets

Tailor-made to the individual.
Generally recommend that people need to consume ~2,300 kJ less each day to lose 0.5 kg/week.
Based on evidence-based diabetes guidelines and dietary guidelines for the general population (when specific advice for people with diabetes or pre-diabetes is unavailable).

Efficacy of VLEDs versus other diets

On average, VLEDs produce 1.2 kg – 3.2 kg weight loss per week in the acute phase in approximately 80% of individuals and are a more effective long-term mode of weight loss than a food-based energy-reduced intervention.
A recent systematic review and meta-analysis of 5 clinical trials where participants consumed VLEDs over 4 – 52 weeks determined that total weight loss ranged from 8.9 to 15 kg in those with type 2 diabetes and 7.9 to 21 kg in those without diabetes.
There is a 3.1-fold greater likelihood of losing 10% clinically significant weight loss at 24 months after a four-month meal replacement diet of 65 to 75% energy restriction (followed by moderate energy restriction for 8 months), compared to a 12 month 25–35% moderate energy-reduced food-based diet.