It is impossible to sustain lifestyle of extremely low calories


If you ever needed proof that fad diets don’t work, this is it.

A new study has mapped out two very different diets – low-fat and low-carb – over a two-year period.

Analyzing dozens of studies over the past few years, the researchers tracked dieters’ body weight in one graph, and their energy intake (i.e. calories consumed) in another.

The figures, published in The Lancet, showed barely any difference between the two diets, and an almost unanimous bounce back to the dieters’ original weight. 

BODY WEIGHT: This line shows a sharp drop in six months followed by a steady bounce back

CALORIE INTAKE: Dieters start by cutting all their calories but gradually consume more over time as they struggle to sustain it. The floating line is what dieters say they are eating

In the first graph, both lines show a sharp drop in body weight in the first few months, before gradually rising – much closer to what it was before. 

Similarly, in the other one, dieters start by cutting out all their energy-filled carbs and fats.

But ultimately, it seems, they cannot sustain that lifestyle.

Over time, the graph shows, they consume more and more energy until they reach a steady intake, much closer to when they started. 

The floating line you see in the middle of the energy graph reflects what participants say they are eating – which bears no relation to their actual calorie intake.

And for anyone trying to find a difference between the diets: there isn’t one. 

Those four extra pounds you lose on a low-carb diet are virtually nothing in health terms.

Drs Yoni Freedhoff, an obesity professor at Ottawa’s Bariatric Medical Institute and Kevin D Hall, an official with the US National Institute of Health, offer an explanation: 

‘Both the low-fat and low-carbohydrate diets resulted in rapid early weight loss that plateaued after about six months at a likely disappointing level.’

That disappointment, they observe, ‘was then followed by slow bodyweight regain’.

Why?

The researchers say there are many factors at play. 

First we have complex physiological mechanisms that prevent weight loss – such as slowing metabolism.

But primarily our bodies cannot go so long with such little input of energy. 

And we struggle to cut out food as a social catalyst.  

‘The typical bodyweight trajectory is primarily driven by (…) an increase in appetite in proportion to the loss of bodyweight,’ they explain.

That is coupled with ‘difficulties in sustaining changes to dietary choices and behaviors that affect patients’ ability to enjoy, celebrate, and socialize with food.’

Fundamentally, Drs Freedhoff and Hall say, this study shows it is futile comparing different kinds of diets. 

The determining factor is the person. 

‘We need to increase our efforts to understand the individual differences between patients that have an effect on diet maintenance and prevent its erosion,’ they say. 

‘Studies should determine how to target effective diets to individual patients.’

They add that we should also look at diet breakers, such as a lack of cooking skills, lack of healthy food resources, or demanding schedules that make fast food more convenient. 

‘After all, as with every chronic disease, successful obesity management requires lifelong treatment,’ they conclude.

‘There is a pressing need to help patients navigate day-to-day realities in the face of maintaining a permanent and intentional behavior change. 

‘We also need to better understand how family, community, and society as a whole can help support and sustain healthy lifestyles.

‘Fewer resources should be invested in studying whether or not a low-carbohydrate diet is marginally better than a low-fat diet, or whether intermittent fasting provides marginally better short-term outcomes than a so-called Paleo diet. 

‘Crowning a diet king because it delivers a clinically meaningless difference in body weight fuels diet hype, not diet help.

‘It’s high time we started helping.’